Questions on: Christmas Cactus
Ron Smith, Horticulturist, NDSU Extension Service
Q: I enjoy your Web site! Please send me information for the propagation of Christmas and Easter cactus and information on air-layering of plants. (e-mail reference)
A: Thank you! You can download it yourself in a heartbeat at http://www.ag.ndsu.edu/pubs/plantsci/landscap/h1257.pdf.
Q: I purchased a Christmas cactus that was full of buds and flowers. After a couple weeks at home, all the buds fell off. What would cause this? (e-mail reference)
A: Moving the plant from a florist or greenhouse environment to a home environment in winter where the humidity goes from 60 percent or higher to one where the humidity is 10 percent or less will cause the flower buds to drop. Christmas cactus is a forest cactus that lives in constant high humidity. Eventually, the plants acclimate to our low home humidity settings and bloom beautifully. Be patient. Eventually, the plant will grow ample, beautiful flowers.
Q: I read through all the pages about Christmas cactus care and problems. My plant stems near the soil look like they have been stressed. Some of the leaves have transparent spots on them. I only water when my gauge says dry or low moisture and fertilize with Miracle-Gro. The plant was repotted, so I wonder if I put it in too big of a pot because I know they like to be root-bound. I have another plant that I repotted. Half of the stems broke off and other stems are breaking off. What could I be doing wrong? (e-mail reference)
A: What you are probably seeing is the plant tissue becoming corky because of age. Usually, this is nothing to worry about. As for the leaves that are showing transparent spots on them, if there are just a few, go ahead and remove them. This is often the beginning of edemia caused by keeping the soil too moist. The breakage and falling of some leaves is a pretty good indication of the air being too dry. Keep in mind that these are forest plants that live in the understory of tropical forests. I suggest that you go to http://www.ag.ndsu.edu/pubs/plantsci/landscap/pp744w.htm for further analysis of your plant’s problems. Perhaps something at this site will help you identify what the problem is with your plants.
A: You certainly can, but I don’t recommend it. From a sanitation standpoint, it would be better to root any new slips in separate containers in case of disease problems that are not visibly evident. Once you see them successfully established and growing in your own environment, then you could do the integration to have the mixed colors.
A: From the photo you sent, it looks like a Christmas cactus (Schlumbergera species). The reason for nonflowering likely is due to it not having the required number of hours of short days (long nights). The plant should receive 13 or more hours of continuous darkness starting around the end of September or the beginning of October. This action sets the flower buds after about six weeks. For extended blooming, try to keep the plant in a cool setting away from forced-air heating vents or any sudden cold drafts from open windows or doors.
Q: I have a Christmas cactus that is about five years old. The plant never has bloomed, but it has grown quite large. The branches are falling off at the dirt level and some of the leaves are curled. Also, the stocks of some branches have brown streaks and some of the branches are limp. I don’t know what to do to correct the problem. (e-mail reference)
A: I suggest visiting my Web site atto see if you can pick up some clues for what is ailing your plant. My best advice, based on what you have told me, is to prune off any limp branches and any that have brown streaking on them. You also might want to trim off some of the healthy material as well to reduce the weight that is causing some of the breakage. These plants bloom as the amount of daylight becomes shorter. Christmas cactus can be forced to bloom indoors using the same treatment. My guess is that this plant never has had the daylight shortening requirement met to set flower buds. In order to get this to happen, the plant needs to be covered for about 13 hours each night (absolutely no light reaching it) beginning around the end of September or early October. You didn't say what kind of container it is in or whether it ever has been repotted. Use a free-draining, porous clay pot.
Q: When and how often should I fertilize my Christmas cactus? What fertilizer should I use? The cactus is blooming at this point. Should I fertilize it now or wait until the flowers fall off? (e-mail reference)
A: I have a Web site exclusively dedicated to Christmas cactus at www.ext.nodak.edu/extnews/hortiscope/houseplnts/xmascctus.htm. Basically, wait until the flowers cease. During the spring and early summer, fertilize every 14 days with a 10-10-10 mix or with something similar.
Q: What soil should I use to repot my Christmas cactus? When do I know that I have to repot the cactus? I've had it for years and never repotted it. It's flowering and looks great, although only half of the plant has flowers, which is kind of weird. Last year, the whole thing flowered at the same time. (e-mail reference)
A: You are better off purchasing a high-quality, all-purpose potting soil mixed with about 30 percent sand or what is known as a bromeliad potting soil mix. Whatever product you select, be sure it is a quality product that is pasteurized or sterilized. Try to resist the temptation to repot this plant! It thrives on being pot-bound to flower. If you think it needs soil, add some to the top of the pot. If you do repot, do not step up to a larger size. Wait until the plant stops flowering and then refer to the details on my Christmas cactus culture and care Web site at www.ext.nodak.edu/extnews/hortiscope/houseplnts/xmascctus.htm. Christmas cactus needs more than 12 hours of continuous darkness every 24 hours. Very likely the part of the plant that is not flowering was exposed to low-level light that kept it from setting flower buds.
Q: I have a Christmas cactus that turned brown, but you can see green under the brown. The plant is growing, but it has not bloomed since I got it. I have repotted the plant and given it some Miracle-Gro. What am I doing wrong? (e-mail reference)
A: I cannot determine what you are doing wrong based on what you have told me. Christmas cactus is a fairly easy houseplant to grow. If you are guilty of anything, it is probably giving the plant too much water. Go to my Web site at www.ext.nodak.edu/extnews/hortiscope/houseplnts/xmascctus.htm. The Web site has dozens of questions and answers on this plant species.
Q: My mom had three Christmas cacti. They used to be different colors, but now they are all white. Why did this happen and is there a way to make them colorful again? (e-mail reference)
A: You are asking a very good question! If you had said that one plant was changing color, I would attribute that to possibly a genetic material break, but not with all three plants doing the same thing! It must have something to do with the environment or cultural practices. I am sorry, but I can't give you a solid reason at this time. Perhaps some column readers can provide an answer.
Q: I have a Christmas cactus that is full of buds, but the soil is very dry. I am afraid to water it because last year I gave it a nice drink and the buds started to fall off. Should I give it a drink? (e-mail reference)
A: You need to maintain a fairly constant watering schedule with any flowering plant. Reduce the watering a little at this time, but do not eliminate it. I would suggest watering enough to moisten the top few inches of soil, not a good soaking after a dry period. Flowers (leaves too) often will abscise if an extended period of dryness is followed by an irrigation event that completely saturates the roots.
Q: I discovered you through a Web search I performed about old-fashioned Christmas cactus. My mom had one, but it died several years ago. I have been looking to replace the cactus, but have not found one. I’m hoping that you can tell me where to purchase a plant. I didn’t know that Christmas cactus was that rare. Anything you can do would be appreciated. (e-mail reference)
A: I don't know of any source, but since the column is widely read, perhaps someone will know of a source and respond to me. If that should happen, I will connect you with the information.
Q: My Christmas cactus is starting to get flower buds. I'm keeping it in a cool, dark place for longer hours and have limited my watering. I was told that now is a good time to fertilize. Is this true and what do you recommend I use for a fertilizer? (e-mail reference)
A: This is the time to apply a liquid fertilizer with a 1-1-1 ratio, such as 10-10-10. Fertilize again in February. Keep the watering to a minimum. Allow the top inch to dry completely.
Q: I have a Christmas cactus that is growing mold in the soil. I repotted it, but the mold is reappearing and spreading to the edges of the pot. It's white and fluffy, but there are patches where it turns yellow, solid and upright. What can I do about it and will it harm my plant? (e-mail reference)
A: It will not hurt your plant. This is a saprophyte that is growing and digesting the rich organic matter in your potting soil. These are healthy microorganisms at work. The same would be true if you saw mushrooms growing, too.
Q: I have a Christmas cactus that is doing great. I would like to clip off some leaves and start a new plant. Should I put the new clippings in water (and for how long) or plant the clippings in soil? (e-mail reference)
A: Both ways are acceptable. If you are going to plant the clippings in soil, I would encourage you to use a sand/peat mix (50/50) and keep the media moist. The clippings should root for you in a few weeks, and then repot the new plants.
Q: I bought a Christmas cactus plant that I water when it is dry on top. Lately I have noticed little, black, gnat-looking bugs on the plant. What is a safe way to get rid of them without killing my cactus? (e-mail reference)
A: I would suggest repotting with fresh potting soil that is pasteurized. These are likely fungus gnats that are feeding on the organic matter in the soil mix, which was probably not a pasteurized mix to begin with.
Q: How do I start a new Christmas cactus from my old plant? Does it work to break off a piece and stick it in some new potting soil? Would this be the time of the year to try to start a new plant? (e-mail reference)
A: Please go to my Web site on Christmas cactus at www.ext.nodak.edu/extnews/hortiscope/houseplnts/xmascctus.htm for all kinds of information on working with this plant. In response to your direct question, here is my answer to a similar question on the Web site. All she needs to do is cut off sections of the stem consisting of two or three joined segments. Allow them to dry for a few hours and then push them into a 3-inch pot that has the same potting soil as the mother plant does. Treat the cuttings as mature plants and in about four to six weeks, the cuttings should have rooted and begun to show some new growth. This will not harm the mother plant. Good luck and enjoy!
Q: I inherited a Christmas cactus after my mother passed away in August. I tried before to care for a piece that belonged to my great-grandfather, but it died. My mother's cactus is part of the one owned by her grandfather. It was doing great while she cared for it. Since I've had it, most of the plant looks fine. However, a section kept wilting. Today I was able to peel a part of the bark from the stem, but that part of the plant pulled out of the soil. The part that came out is substantial, approximately 15 inches of the plant! I don't know what to do. I put the section into water to see if I can get roots to form, but won't that rot the plant? Should I cut sections off and try to root them? I really don't want to lose this plant and am desperate for some help. This Christmas cactus was my mother's pride and joy, partly because it looked so great and because it was a piece of her grandfather. I told my mother I wouldn't be able to properly care for it and I feel as if I am letting her down. If you have any advice, please pass it along. (e-mail reference)
A: Take some sections and root them in a sand/peat media. Keep it moderately moist and in bright, indirect light. The sections should root for you in about six to eight weeks.
Q: I have a Christmas cactus that just got through blooming. I might need to replant it in a bigger pot. What kind of potting soil should I use? (e-mail reference)
A: Use a potting soil high in organic matter. It is called African violet potting soil in some outlets.
Q: I am getting ready to repot my Christmas cactus. It is definitely rootbound. I know this is good for the plant, but should I just pop it into the bigger pot or should I cut a small portion off the bottom of the roots? I also was told that when the flowers die to let them totally dry and then pull off the flower and the leaf it is connected to. They said there should be a new bud on the next leaf. Is this true? (e-mail reference)
A: Scoring the roots with a knife would help them move into the new media. I don't know who your source was concerning the removal of the flowers, but I have never heard of that practice before, so I can't tell you if it is true. If you want to take a chance on the advice, go ahead and give it a shot. It shouldn't hurt the plant one way or the other.
Q: I have two Christmas cactus plants. The soil became so dry that it pulled away from the side of the pot. I repotted the plants in soils used for succulents and cactus. I watered the plants thoroughly after four days. The plants are near an east window and have done well up to this point. Now the leaves feel thin, shriveled and drop off easily. Did I kill it? (e-mail reference)
A: You may have repotted the plants too deep. Pull some of the soil back. Remember, it was doing fine in the scrawny soil it had, even if you didn’t like the looks of it.
Q: I’ve had a Christmas cactus for about four years. The second year I had it, the outer leaves turned a light purple-pink (the color of its flower). The base leaves are still green, but fades into a light green-white to purple. The leaves have been that way ever since. It flowers well and seems to be doing OK. I’ve never fertilized it. Could that be the problem? (e-mail reference)
A: You are seeing the magic of plant color expression based on a stress factor, which is probably caused by the lack of certain nutrients. Many times the coloration you describe is due to the breakdown of chloroplasts and the expression of anthocyanin and xanthophyll. Anthocyanin is a flavonoid. A major function of anthocyanin is to provide color to most flowers and fruits. The colors can help attract pollinating animals to the flowers and animals that will help disperse the seeds. Anthocyanin also is thought to help protect the leaves from ultraviolet radiation, but some botanists think that may not be true for all plant species. Anthocyanin also is thought to deter herbivores in some species. Xanthophyll is a carotenoid. The main xanthophyll in leaves is lutein. Xanthophyll is a structural component of the light harvesting antenna in chloroplasts. They function as accessory pigments for harvesting light at wavelengths that chlorophyll cannot and then transfer the light energy to chlorophyll. They also absorb excess light energy and dissipate it to avoid damage in what is termed the xanthophyll cycle. The xanthophyll zeaxanthin appears to have a role in sensing blue light, which is involved in stomata opening and in phototropism. All said, your fertilization may “erase” the coloration that you describe. Make sure the plant is not too pot bound, which could result in the roots not taking up adequate nutrients.
Q: I recently became the proud owner of two Christmas cacti. The one purchased from Homewood Nursery in North Carolina (they participate in poinsettia cultivar trials) is doing great. A section fell off during the trip home, but I have it rooting in water. My future mother-in-law gave the other plant to me. I was told that it is about 15 years old and from her grandmother’s funeral (no pressure here!). This gift consisted of two long arms falling to one side and brushing the floor. It is in a 6-inch pot, so it’s not a pretty picture. I trimmed the arms back, leaving about five sections on each of the two and started rooting the removed pieces. When is the right time to repot the original? Can I pot the clippings with the original? I also have considered potting the section that fell off the one purchased from the nursery with the older one. (e-mail reference)
A: Just in case, keep the two plants separate. Repot everything in the soil that you want them to grow in. You have a unique opportunity to root all of these cuttings into small, decorative pots and pass them out to your new family after the wedding, if there is enough time. At your first opportunity, pot the mother plant into the next nominally sized pot with the same drainage characteristics as the original.
Q: When is a good time to transplant a Christmas cactus? Should it be pruned when transplanting? How much light does it need? Is a southeast window too bright? (Lake Park, Minn.)
A: Visit my Web site about Christmas cactus at www.ext.nodak.edu/extnews/hortiscope/
houseplnts/xmascctus.htm. There are dozens of questions that have been answered that can help educate you about your plant. In answer to your questions, Christmas cactus can be repotted shortly after it has completed flowering, but don’t do it every year, as flowering actually is encouraged by the plant being pot-bound. You don’t need to prune it unless your intention is to propagate more plants from the cuttings. Having the plant in a southeast window should not be a problem. If it appears to be getting sunburned, move it away from the direct sunlight.
Q: I have three Christmas cacti that are over 25 years old. While I lived in New York, I put them out on the porch. I brought them inside at the end of September, before the heat was turned on. I withheld watering from Aug. 1 to Sept. 1. My plants had beautiful blooms from December through April. When I moved to Florida, I was concerned they would not survive the move. I put them on the patio under a cover. They were in light, but not direct sun. I again withheld water, but this time from September through Oct. 1. In the third week of December, they started to bloom and were covered with flowers through May 1. I think withholding water and the cool nights are responsible for the lovely flowers. I water once a week, but don’t give them a lot. Hope this will help others who have problems. I enjoy your column and find helpful information in it. (e-mail reference)
A: Thanks and congratulations on finding the secret that works for you to get the cactus to bloom when you want them to! I know many readers will appreciate knowing this information!
Q: Are Christmas cactus, orchids and goldfish plants in a poisonous group? I have a few houseplants I’m trying to keep away from my 18-month-old granddaughter. (e-mail reference)
A: They are not listed in any of my poisonous references, but I still wouldn’t take a chance with any of them. You don’t want to be the first to discover that one of these does have some poisonous factor that is toxic to children. Most poisonings are reported in livestock, which are larger than humans and therefore it takes more to kill them. Not too many livestock have access to the plants you mentioned, so put the plants out of the child’s reach to be on the safe side.
Q: I’ve been trying to start a little window garden and so far it’s coming along great. Recently I took a clipping of a Christmas cactus from my neighbor’s plant. I set the clipping in water and now roots have developed. They’re about a half-inch long. When would be the right time to pot it? Should I do it now or wait for the roots to develop further? (e-mail reference)
A: It depends on the length of the cutting, which I am sure is longer than a half-inch. I would suggest waiting until the roots are about the length of the cutting, then transplant.
Q: I have a Christmas cactus plant that looks very healthy. I water it only when dry. It’s located in a well-lit area but not in direct sunlight. Despite the care, it has never bloomed. (Email reference)
A: You might actually have an Easter cactus rather than a Christmas cactus. These plants (both of them) need a resting period by decreasing water and warmth. They should be put outdoors in summer to set the buds for next year. That said, many people have had overwhelming success by not following those directions. But give it a try and see if it helps. This is what professional growers do to get them loaded with flower buds to make them irresistible on the market.
Q: My mother had a Christmas cactus for about 40 years. She had Alzheimer's and forgot to water it for six months. I rescued it and even though it was hanging and had paper thin leaves, it came back after about three months. I've had it hanging from my ceiling on the east side of my house for three years. I water it once a week. It looked great until about two months ago. The leaves are drooping and look dehydrated. Should I repot it? (E-mail reference)
A: Give it a rest period for about six weeks. We learned from your mother the plant can survive. During that period, water it only enough to keep the soil from drying out completely. It could also have a disease. Take cuttings right away and get them to root in case the disease has advanced to the point of being lethal.
Q: My Christmas cactus has healthy, dark green leaves and flowers several times a year. For some time now whole branches fall off after flowering or even while the flowers are open. It appears that the stem is rotting just above the soil line. What can I do to save this plant? (E-mail reference)
A: About the only thing you can do, based on your description, is to take some root cuttings from the remaining healthy foliage. Stem cuttings are the best alternative at this point because the plant sounds like it is doomed.
Q: I have a Christmas cactus that is wilting and looking pale and bleached. I put in into a new, bigger pot and fertilized it. I give it as much sunlight as possible and water about every three days. Any suggestions? (E-mail reference)
A: Back off on the watering and don't add fertilizer. Water only when the soil is completely dry. Fertilize when there is evidence of new growth. Don't try to force it into growing with fertilizer. The plant does not need direct sunlight so that could be causing the bleaching.
Q: My neighbor has a huge Christmas cactus. She wants to give me a starting but is not sure how to cut or pull out a section so it will survive. I don't want to be responsible for her plant dying just because I want a starting of my own. It was her mothers and she has recently passed away. (E-mail reference)
A: All she needs to do is cut off sections of the stem consisting of two or three joined segments. Allow them to dry for a few hours and then push them into a 3-inch pot that has the same potting soil as the mother plant does. Treat the cuttings as mature plants and in about four to six weeks they should have rooted and begun to show some new growth. This will not harm the mother plant.
Q: My Christmas cactus is dropping leaves in what I would call a "molting" effect. Is there something I can do to correct the problem? (E-mail reference)
A: The water may be too cold. It may be in a draft of hot or cold air. The light intensity could be too low or you could be overwatering. Any of the above could cause the symptoms you describe.
Q: My Christmas cactus recently dropped its last leaf. Is that OK or does that mean that it is dying? I’m keeping it in a sunny area. Should I do anything else? (E-mail reference)
A: If the stem is not mushy, there is still hope. It depends on your patience. Keep it in direct sunlight as much as possible and do not overwater. It may send out new growth as spring approaches and the days get longer.
Q: We have a Christmas cactus that I’m guessing is about 25 years old. It has been pruned so it appears almost like a tree. It is beautiful when it flowers but recently I noticed a limp branch that fell off when I touched it. Where the branch broke the inside core is fibrous and shriveled and there is a gap where it looks like the core shrunk away from the outside bark. I am not sure if I should cut it back or just leave it as is. (E-mail reference)
A: I wish I understood the Christmas cactus better myself! If I ever get a graduate student interested enough, I'd have the student do an international search on this plant species and conduct at least two years of research on all the hybrid variations of this species that exist. I’d also have them study all the cultural nuances that could possibly come up. I wish the plant was not referred to as a cactus because it places it in the realm of a desert species for most people. It is a species that is native to the tropical forests of Central America. They grow as epiphytes (above ground) in the limb structure of mature trees where decaying organic matter has collected. It has the ability to form abscission layers between the various limbs or leaves when things begin to dry up too much either through the soil or air. I think that’s what happened to yours so it’s not a disease, just a plant's reaction to the dry conditions (you live in Vermont and have been using your central heating system, I am sure!). I suggest monitoring to be sure the condition does not progress but I don't think you have anything to worry about. Don't prune it until it begins active growth again sometime in March or April. Check the plant for mealy bugs, as they are a common infestation of this species, which could cause the limpness that you describe. If present, dab them off with a Q-Tip dipped in rubbing alcohol.
Q: My Christmas cactus is very old as it belonged to my husband's grandmother. In the past it has had lots of blooms. Last spring it had only two buds. I moved it to a new location that it seems to like. It has lots of new growth but has just started growing tiny root like buds in most of the joints. Can you tell me why it is doing this and what I should do to get it to bloom once again? (E-mail reference)
A: The buds are likely the start of aerial roots that sometimes form on tropical cacti, which is nothing to worry about. These plants need short days and cool temperatures to get them to flower. Cover the plant with something that excludes light 100 percent at twilight. Keep it covered for more than 12 hours. Eventually the buds will form. You can stop covering the plant when that happens.
Q: We have an almost 100-year-old Christmas cactus that my husband’s grandmother gave me about 12 years ago. Since getting it, it has gotten bigger and much more dense. She kept it in part of the house that had no heat but it still flowered a great deal. I’m surprised it never froze and she even rooted cuttings in ice water and they bloomed too! Because it stays outdoors here every summer, it grows more in an upward fashion rather than hanging like some do. It's in an 11-inch clay pot and, when watered, it weighs 22 pounds. (E-mail reference)
A: What you’ve told me just proves that plants can get along very well under less than what we think are ideal conditions. So often we think our prescriptions for plant care will do the trick, when all we need do is let nature take it's course. Thanks for sharing!
Q: I have a Christmas cactus that is approximately 20 years old. It stopped blooming for various reasons. It is in a ceramic pot that has it's own base for good drainage. However, along the top and bottom there is a large amount of salt build up. At least I think it’s salt. It is powdery and almost rust like. It is on the pot but not the plant. I wash the pot frequently but the salt continues to come back. How can I stop this build up of salt? I believe it’s the reason it stopped blooming. Would a plastic pot be better? (E-mail reference)
A: Salt buildup comes from the water source and is not uncommon in ceramic or plastic pots. Occasionally water the plant with distilled water to flush the salts out of the rootzone. This presupposes that the pot is freely draining and that the owner will dump the excess water flowing into the saucer within 30 minutes after watering. You might be watering with soft water, which is high in sodium salts, or your water may be naturally high in soluble salts. If you think a plastic pot would work better for you, give it a try.
Q: I have a 25 to 30-year-old Christmas cactus that has developed root rot (no spores visible). I have lost three major trunk branches and am starting to loose another. I have repotted in new soil and have been very careful with watering but it doesn’t seem to be working. I read about digging it up and cutting out all the dead material from the trunk then replanting. Will it work? How about chemicals? (E-mail reference)
A: The plant should re-root if you remove all of the decay and replant it in a sterile media. It doesn’t need chemicals. The single segments should root quite easily, almost like weeds. Be sure you have them properly oriented, stick the distal end into the soil or media for rooting, not the apical end.
Q: I have a Christmas cactus that is in a southern window. During the winter it thrived, bloomed and grew an amazing amount of leaves but seemed to require a lot of water. Now the leaves have started turning purple. It is in a temperature-controlled office with no drafts. What should I do differently? I tried reducing the amount of water but clumps of stems starting falling out! (E-mail reference)
A: It sounds like a trace mineral deficiency so try some fertilizer. Look for something that includes both major and minor elements.
Q: I have a Christmas cactus that is more than 60 years old and is very large. I can no longer move it or repot it. This year it's not looking very well. I think it's just too big. Can I cut it way back without killing it? (E-mail reference)
A: I cannot answer that question. I would suggest that as you make your cuttings, try and root some of them. Many if not all, should develop a root system for you. Just stick some in a 50/50 sand/peat mixture, and keep moderately moist.
Q: I live in an apartment building which has a community room that is quite warm. The temperature is kept at about 75 degrees. We have two Christmas cactuses which seem to be thriving. The problem is that they seldom bloom. Could it be too warm for them? They are kept in front of a south window so they get lots of sunshine. Can you tell me how to care for them to make them bloom? (Warren, Minn.)
A: It is likely too warm and the plants probably don't get enough darkness hours to set flower buds. You should move them to a cooler location about the end of September and cover them each night to keep all light out for at least 12 ½ hours. For example, covering them at suppertime around 6 p.m. and uncovering them at breakfast around 7 a.m. will give the plants enough darkness to set flower buds in about six to eight weeks. It would be best if they could be kept in a north or east window.
Q: Recently a basketball fell on my Christmas cactus breaking of three stems with roots. The plant is just starting to bloom and has about five stems with roots left. Will my plant survive? (E-mail reference)
A: Just continue to give it the care you have in the past, minus the dropping basketball.
Q: I have a Christmas cactus that is 10 years old and has been quite healthy. But I have noticed some white fuzzy stuff around the joints of the leaves. It doesn't appear to be mold. It is still flowering and I wondered if it would be okay to repot it now? (E-mail reference)
A: It is probably an insect known as either the cottony cushion scale or mealybug. Take a Q-tip and dip it in rubbing alcohol and rub those critters off. They are not doing your plant any good. Monitor over the next couple of months to be sure they are not coming back. It is difficult to get rid of the insects on the first try.
Q: I have several Christmas cactus plants. They stay green but don't grow or bloom. The last one I bought had buds on it but didn't bloom. Can I put more than one plant in a pot? If so, how many in each pot and how big a pot? Should I take the dead buds off even though they eventually drop off? Is it true that if you move the plant it will not bloom? (Aberdeen, S.D.)
A: Pot size makes little difference. I have seen three plants growing in a 6-inch clay pot then each plant moved into a 6-inch pot when they were transplanted. This species of plant is generally day-length sensitive. It performs best in cool rooms where the temperature is hovering in the mid-60's. Its blooming is poor and short in duration if the room is too warm. Begin covering the plant, about the end of September, as the sun goes down around 5:30 or 6:00 and keep it covered (must be light-proof) all night long. Remove the cover when everybody leaves the house in the morning – around 7:00 a.m. This will trigger bud set over the next several weeks. When they become apparent, covering is no longer necessary. By that time you will need to heat your home which dries out the air. In some instances, this dry air causes the buds to abort and not open. However, in some cases it doesn’t affect the buds at all. If it becomes evident that the buds on your plant are in need of misting, then do so on a daily basis using distilled water. Christmas cactus like bright, indirect light. Keep the plant on the dry side while it is undergoing photo-period response development. Allow the soil to dry about 2/3 to 3/4 of the way down, then water just enough to rewet the entire soil mass. During the vegetative stage you can increase the watering frequency. Bloomability is not dependent on whether or not you move it, but whether or not you have met the above requirements. Some people have the good fortune of just setting their plant in an east-facing window, not altering the watering or anything else during the year and the plant still blooms profusely. So don't look for justice in growing plants!
Q: I have a problem with my Christmas cactus. It blooms well but now the leaves are pinkish - red and look wilted. Should I be repotting it since it looks brownish near the soil. (E-mail reference)
A: Repotting is a good idea and you should cut back on watering. When repotting, examine the roots and lower stems for rot. If it has rot, as I suspect, make some clean cuts back to the healthy tissue. This may mean that you will have to literally re-root the plant or pieces of it.
Q: I have a Christmas cactus that had very nice blooms when I brought it up from the basement for the holidays. Since then the blooms have died so I'm wondering if I should keep watering it. This plant is especially precious because it belonged to my mother. (E-mail reference)
A: During the winter months these plants need to be kept on the dry and cool side. In April, assuming you live in the northern part of the country, go back to normal watering and care.
Q: I have a Christmas cactus that is at least 30 years old. Last year it bloomed beautifully but this year it is limp and loaded with buds that are dying without opening. I have it in a west window but not in direct sunlight . Up to now it seemed to love that location. It gets watered once a week but only if needed. It’s located close to a heat vent. Could that be causing the problem? I had it split and repotted about four years ago and last year is the first year it bloomed so well. (E-mail reference)
A: You identified the problem with your inquiry. Get it away from the heat vent ASAP and begin misting the foliage to keep the blooms from falling before they open.
Q: My Christmas cactus was doing well this season. It had lots of flowers for the holidays but then my cat decided to do some pruning and broke off several stalks at the soil line. I just laid the leaves on the rocks that are on top of the soil. Yesterday I noticed they are sprouting little roots. Now what do I do?
A: Plant them!
Q: I have a 5-year-old Christmas cactus that loses large pieces of the plant after blooming. After losing pieces of the plant it starts to wilt really badly. What am I doing wrong? I would like to turn the problem around so it looks like I've had it for five years not one. (E-mail reference)
A: I think the biggest "sin" committed by keepers of Christmas cacti is overwatering. A very well-known person in our department, who has a pretty good green thumb, is slightly guilty of such treatment and has cooked the goose of a couple Christmas cactus plants over the years. At this time of year, from January through the end of March, the plant should be watered sparingly. Prior to that, from late September to mid-November, treat it the same - water sparingly. Other times of the year water thoroughly when the potting soil dries, but be sure to pour off the excess water that drains into the saucer the pot sits in. You likely are overdoing it if you are watering it more than once a week.
Q: I just got a Christmas cactus but it did not come with any information on how to take care of it. How do I water it and what should I do with the old blooms? Also, what kind of food does it need? (E-mail reference)
A: After the flowering period, which is now, allow the plant to go into a resting period which means keeping the plant cool and watering infrequently until about the end of March. Then water thoroughly when the compost begins to dry out. When all danger of frost is past, you can summer it outdoors in a shady spot, making sure slugs don't find it. Bring it back inside in September before any frosts, reduce watering, and cover all night long for more than 12 hours until buds begin to form, then don't cover any more. Once flower buds form, increase the watering, and the cooler you can keep the plant, the longer the blooms will last. During periods of active growth, fertilizer about every two weeks with a houseplant fertilizer such as Schultz's. Take cuttings and root them to perpetuate the plant as it ages.
Q: I have had a Christmas cactus for five years and every year there are more blooms. It is beautiful but how do I keep the leaves clean? I would appreciate a home remedy because I live in a rural area so certain items aren’t always available. (E-mail reference)
A: Move it into the bathroom if you can and rinse the blooms with a gentle spray of tepid water. Glad to hear yours is doing well. Keep up whatever you are doing!
Q: I have a Christmas cactus that was propagated from a friend’s plant. It did not flower the first year. This year I’ve covered the plant every night for 12 hours since mid-October. A couple of weeks after I did that, buds started to come out. Now it has started to blossom. The color is supposed to be pink but mine is mostly white/cream with only a little pink showing. Is it supposed to do that on first blossom or am I doing something wrong? I stopped covering it a week ago. Should I go back to covering it every night? The plant is near a north window. (E-mail reference)
A: You have done nothing wrong but you do not need to start covering your plant again. Once initiated, the flower buds will continue to develop and open. Often flower color, like fruit color (in apples for example), is a chimera, or a bud sport. Without creating an academic explanation of this interesting phenomenon, it basically represents a vegetative or somatic change in the genetic make up of some cells. The cutting you got from your friend might have had the red flower color as a chimera. The mutation was lost when you propagated it and it reverted back to the original color. Or (to make this even more confusing!), your flower color could be a chimera. The long and short of all of this, don’t worry. Enjoy your Christmas cactus for what it is doing, regardless of the flower color. Who knows, as more blossoms open, you may find even more interesting flowers to ponder over!
Q: Is Christmas cactus poisonous to my cats? (E-mail reference)
A: Christmas cactus is not listed as a poisonous plant but that doesn't mean that it cannot make your kitty sick. The grower may have had the plants treated with systemic pesticides or the cat could be allergic to the plant's juices. Basically, it is not a good idea to allow your cat to eat anything green that you haven't grown yourself and know it to be free of toxins.
Q: We take our Christmas cactus outside and place it in the shade under a spruce tree. The plant is watered only occasionally and left outside until just before frost. We then take it back into the house, water it, hang it in the light and it starts budding right away. I can't figure out how to get it to wait at least until Thanksgiving. If they don't bloom, I can get a new one for $2. I was given a Norfolk Island pine. It's over three-feet tall. Over time it lost all its branches except the top two which are showing new growth. Should I run or fight? If I cut the top off, will it re-root? Will the root grow new shoots? The original one we have is healthy and is over 6-feet tall. (E-mail reference)
A: Interesting reversal of the typical problem! I can only suggest that keeping it at lower temperatures. Keeping it at approximately 55 degrees F would slow down the bud development and opening somewhat, hopefully until Thanksgiving. The Norfolk Island pine can be air-layered. If you are interested in the process, send me your mailing address and I will send you the publication, Home Propagation Techniques, where it is described in detail along with other propagation information.
Q: I have two Christmas cacti which have turned brown (bark-like) right above the soil. Is this a major problem? What causes it and how do I correct it? (E-mail reference)
A: If the coloration is firm and not spongy and the rest of the plant appears healthy, then you have nothing to worry about. It’s most likely some mature tissue development. If the plant is droopy and/or discolored, then it could be a fungal canker that will eventually kill the plant. If so, I suggest taking cuttings and rooting them to perpetuate the plant.
Q: I have a 3-year-old Christmas cactus which used to bloom beautifully and did just fine on watering every 2 weeks. But for the last few months I've noticed that it isn't as green as it used to be and the ends of the stems are pink/red. I tried repotting it in cactus soil about a month ago and it hasn't helped. The pot drains pretty well and I keep it near an east window. (E-mail reference)
A: Knock the plant out of the pot and see if the base of the stems are soft or spongy which would indicate the plant is rotting. If so, you can try saving it by cutting the decay back to fresh, firm tissue and repotting. Other than that possibility, I can't come up with any other suggestions based on what you have told me.
Q: I’ve had a Christmas cactus for a couple of years but I never got it to bloom. What are the secrets to making it bloom? I know it needs to be kept in the dark during October, but do I continue to water it? (E-mail reference)
A: The eternal question of getting a Christmas cactus to bloom. Beginning in the fall, and through the winter, give the Christmas cactus only a little water, keeping the soil barely moist. It needs 12-plus hours of uninterrupted darkness, in a cool room (55 degrees F. best) and plenty of direct sunshine during the day. Keep up that regime until buds form on the ends of the leaves. Once set, they will continue to develop and open, their rate and longevity dependent on the temperature of the room the plant happens to be in - the cooler the better.
Often what happens is the buds form and then drop off without opening. It’s due mostly to low humidity and high room temperatures in the winter. If you can tolerate it, keep your house at 65-70 degrees. Set the plant on a bed of pebbles immersed in water. That will keep the humidity high around the plant. Having said all of this, I know of at least a half-dozen people who never go through this routine and have a beautiful flowering Christmas cactus every year. Some people just have a magic touch!
Q: I've got a plant book that discusses how to get your Christmas cactus blooming for Christmas. Give it a good drink of plant food that will last quite a while. By Oct. 1 put a dark sack or something over it and leave it covered till the plant is covered with buds. Then take the cover off and by Christmas you should have your Christmas cactus covered with beautiful flowers. I ended up with too many plants so I am giving all but 3 away to anyone who wants them. They are all bug free because I've never put them outside. Anyone that wants plants can call (701) 285-3378. (Carrington, N.D.)
A: Thanks for the reminder. I'll publish this with one minor correction. Remove the cover every day and recover again at 6:00 p.m. The plant needs 12-plus hours of total darkness each day for about six weeks to set the buds.
Q. To the lady having trouble with her sheepnose apple grafting, she might try winter banana apple interstem. Also, how to tell an Easter cactus from a Christmas cactus: the leaves are shorter and fatter and trimmed with a red tint. (Bemidji, Minn.)
A. Thank you for writing and providing this interesting information. I am sure our readers will enjoy it!
Q. Can you tell me what is wrong with my Christmas Cactus? I don't know if it needs water, or if it had too much water, or what. (Detroit Lakes, Minn.)
A. You are most likely over-watering—or it is in a non-draining container.
It may be a good time to repot now in a free-draining container. Christmas cacti are pretty tough! It would take more than the water you use to kill this plant. Allow it to dry between waterings.
Q. I have a Christmas cactus in bud, but part of the plant broke away at the soil. I think I had it too moist. The question is, can I repot it in the hopes it will grow roots? (Lisbon, N.D.)
A. Contrary to your concern, Christmas cactus can be propagated via stem cuttings. Simply take stem sections containing two or three joined segments, allow the ends to dry for three to four hours, then gently push them into a mix high in peat and sand. They should develop roots in about six weeks.
After root development, repot in a standard soil mix cut 50 percent with the peat and sand combination. While the Christmas cactus will take plenty of water when it is growing, it does not tolerate waterlogged soil.
Q. Can you tell me what is wrong with my corn plant? The bottom leaves are turning brown and yellow and I don't know why. I also have a cacti, but I don't know if it is a Christmas or an Easter cactus. Is there a big difference between the two? (Enderlin, N.D.)
A. The corn plant could probably stand to be propagated. Cut the plant back to about a 6-inch stub, then cut the removed trunk into roughly 4-inch-long pieces. Place them on their sides in damp sphagnum peat, and in about six weeks or so new growth should be evident. Repot the mother plant in fresh potting soil in a free-draining container. Refer to "Home Propagation Techniques" (NCR274).
Yes, the two cacti are different. They are either different species of the same genus, depending on the taxonomist you wish to go with. To me, they will always be different species: Schlumbergera truncata (Christmas cactus) and S. gaertneri (Easter cactus).
Q. My Christmas cactus gets buds, but most of them go limp and fall off before they have a chance to bloom. I pretty much follow my cactus guide to care for it, so I am wondering what I am doing wrong. (Vale, S.D.)
A. With Christmas cacti, they are to be kept cool and dryish until flower buds form and then the water and temperature increased while flowering. Christmas cacti can be either difficult or easy to grow and bloom. Being forest-type cacti, they require a soil high in humus, ample watering following the resting period, summering outdoors in the shade, and not moving the plant once flower buds form. I suspect yours may need repotting, something that should be done after flowering.
Q. I have a Christmas cactus that is 2 years old and always looks wilted. It still bloomed last year, but it doesn't look like it will this year. I water it once a week and keep it in the west window. It is also sitting by a heat vent. Can you tell me what is wrong with it? (Ashley, N.D.)
A. The Christmas cactus should probably be repotted, and the roots examined for disease. Generally, they prefer cool, drier conditions going into this time of year, which it sounds like you are providing.
My only guess at this point is that the plant may be in a container that doesn't drain freely and water could remain in the root zone creating septic conditions.
I find they are somewhat fickle plants. I've known people who treat them like an afterthought and they do beautifully, and I've known others who follow the rules to a "T" and have the plants fail completely.
Q. I read the Hortiscope and really enjoy all your help.
I have an old Christmas cactus. After blooming at Christmas time, it is begging for help. The three center branches get sort of wilted and then fell off at my touch. I am trying to start them again in water. The other branches seem OK only some wiltier than another cactus.
When setting them outside in summer do they need shade and do I leave them in their original pots?
Hope you can help. (Hill City, S.D.)
A. The Christmas cactus should be given less water during the two rest periods it requires every year, right after flowering and the other early in the fall to prepare for flowering.
Yes, summering it outdoors on the north side should benefit the plant.
I suspect that some rot organism got started after flowering, if you maintained your usual watering practices. Leave them in the same container.
Q. I'm enclosing a few pieces of my Christmas (Easter, Thanksgiving) cactus. It has been sick since bringing it inside last fall. There are two plants in the same pot. One is less affected then the other. I just trimmed it severely and sprayed it with bug spray. (Lisbon, N.D.)
A. There was no evidence of insect activity on the plant samples you sent. I would suggest staying away from that practice for now.
What the Christmas cactus needs at this time of year is an occasional misting with distilled water.
The plant samples are showing salt burn or poor drainage. If it is the latter, repot; if it isn't, then back off on fertilization and use distilled water.
Thanks for writing.
Q. I read that somebody wanted to know how to get a Christmas cactus to bloom.
I have an Easter cactus. It is just like a Christmas cactus only it has orange-colored flowers. Mine didn't do much and the last four years I put it out on the deck in a shady place in the spring and in the fall I take it back in the house. It really grew and it blooms four times a year. Last fall when I brought it in the house it had 90 flowers and it isn't a very big plant. It is now blooming again and it has about 45 blossoms. When it blooms again I will take a picture and send you one.
I also started another plant a couple years ago and that has some blossoms. I let these plants get dry before I water them. I keep them in an east or west window.
I have a geranium plant that I keep every year and put in the basement when I bring it in the house in the fall. In the spring I set it outside again on the deck. It had 85 flowers. I have quite a few plants. I water them with Miracle-Gro once a month. If it blooms like that again I will take a picture and send you one.
I enjoy reading your column. (Alice, N.D.)
A. Thank you for the very nice, newsy and informative letter. I will certainly look forward to getting those photos.
Q. Your question and answer section is very informative and I found out that I have a Thanksgiving cactus instead of a Christmas cactus. It always bloomed around Thanksgiving time. Your article explained there are three cacti: Christmas, Thanksgiving and Easter. Last year I lived in a house and my cactus only had four blooms. This year I live in a trailer house and the cactus is in the back room, but gets no sun—just gets light from a window that has lace curtains and venetian blinds that are not open. This year it had 50 blooms. Every sprig had a bloom, a few didn't open, but the surprise now is the cactus is blooming again after only two months of blooming and one sprig even had two buds. One is open already. Isn't it very unusual for a cactus to bloom twice in two months and to have two buds on one sprig?
Thanks for the good information you give. (Jamestown, N.D.)
A. It is unusual, but then the conditions it is growing in are unusual as well. You have unintentionally provided just the right conditions for the plant to bloom like never before. Enjoy.
Thanks for the kind comments about the column.
Q. What is the variety of the enclosed cactus sample? Does it bloom? What care is needed? Why do leaves fall off? What with and when to fertilize? How can a new plant be started? Thank you. (Northwood, N.D.)
A. Your plant is known as Christmas cactus, Schlumbergera spp. Their response to flowering is tied in with shorter days in the fall and early winter. Basically, they should never be placed in direct sunlight since they are known as "jungle cacti," growing as a sub-canopy species in shade, or in filtered light at best. The soil should be kept moist at all times except for a resting period of about six to eight weeks after flowering.
Leaf drop from any house plant is the result of a sudden change in environment—drafts, cold water, new location, etc. Fertilization can be maintained during active growth with Schultz's House Plant Fertilizer or something similar. I suggest monthly applications. Propagate in spring or summer by taking two to three segments of the flattened leaves and sticking them in a peat-based potting soil mixture.
Q. Thank you for your help before. If I get to Fargo, I hope my son can help me find you and show you a couple of plants. It seems like there are little spiders, but my vision is slipping (at 91 that happens, they say) so I can't quite know. Red spots occur and then the leaf turns yellow and dries up on the calla and several amaryllis plants. I don't water and feed the plants as well as I should. Actually, I should dispose of most of them. The Christmas cactus is 67 years old and a gift from my Mother and most plants are gifts.
Have you suggestions for what to do with tuberous begonias? It's too windy here to hang them out.
Thank you. We read all your comments and learn from them. (Rolette, N.D.)
A. Wow, 91 and still going strong--nice to have you around and asking questions.
Calla and amaryllis need an annual rest period. Allow the foliage to dry down and the plants to stay dormant for about six weeks. Then repot, place in a sunny location and water. It appears you are fighting a natural tendency of the plant to shut down.
Christmas cactus is a jungle species as well and needs to go through a wet/dry cycle with growth and need for abundant water from spring to fall. When flowering is over, allow the top part of the soil to dry before watering again. During active growth, they need a tomato-type fertilization on a regular basis.
Try tuberous begonias as pot or bedding plants.
Thanks for writing.
Q. I enjoy reading your column every week.
I am having a problem with my Christmas cactus. It bloomed real nice around Easter, now it is getting these scabby deals on the leaves. Can you tell me what is causing this?
The cyclamen that is almost two years old was cut back when it finished blooming and it keeps coming back and is blooming again. I guess we can keep them growing. Thank you. (Fargo, N.D.)
A. It could be that you are overwatering your Christmas cactus to produce the edema (corky growths) your plant is showing.
The plant should be given two rest periods during the season. One for two months after flowering and the other in early fall to prepare for flowering. It should be kept moist during active periods of growth, and dry during rest periods.
Whatever you are doing with your cyclamen, keep it up! Getting them to rebloom is something that most professional growers don't attempt. Congratulations on your success.
Q: I am having a problem with my 20-year-old Christmas cactus. The leaves are falling off and there are brown, dry spots on the leaves. Is this condition fixable? What do I do? It bloomed beautifully all this time. Watertown, S.D.)
A: The spots on your cactus plant indicate a condition known as edema, due to water-logging. I suggest repotting using a peat-based mix made more porous by adding coarse sand or peat to every three parts of the standard mix. Keep it in the east window. Make sure the pot is free-draining.
Q: I have a beautiful, healthy, Christmas Catus that is loaded with buds. Can you please tell me how to take care of it to keep it healthy? Can I put it outside in the summer, and when is the time to repot it? (E-mail reference, Wentworth, S.D.)
A: Your Christmas cactus will probably fare better indoors than outside, if your winds are anything like ours in North Dakota! If you feel you really must plant it outside, try placing it in a protected location, like an eastern exposure. Taking care of Christmas cactus is basically the same as taking care of poinsettia. Keep it out of sudden drafts, and keep it evenly moist.
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