January 2, 2003

Hortiscope

Ronald C. Smith, Horticulturist
NDSU Extension Service

Q: We started a remodeling project so I put my ficus in the garage under lights because it was too cold for it to be outside. We had a spot of cold weather so I went to check on it and found that the leaves had curled and dried and the bark appeared to have separated from the trunk and branches. Is there anything that I can do to save it? We've had "Ben" for more than 10 years. (E-mail reference)

A: Everything depends on how low the temperature got around the plant during the cold snap. The best advice I can give you is to monitor for any new growth. This will require patience on your part and treating it as if it were alive; locating it in a warm, well-lit location, watering when the soil dries but not over-watering. Do not fertilize it until or unless new growth is noted, then only at half strength. These are pretty tough plants. My wife "rescued" one years ago that had been put on the curb to be picked up by the trash hauler. I had a fit because it looked so scrawny with no more than a dozen leaves on it. But she pruned it and nurtured it back to health in spite of my misgivings.

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: We live in Minot and are planning a wedding on June 21. It will be a garden wedding. Will the cottonwoods be dropping their seeds and cotton at that time? (Minot, N.D.)

A: I'm pretty good, but not that good! So much depends on the weather - they could or could not be dropping their cotton at that time. There must be someone who is a Master Gardener in that area who keeps track of such occurrences. I suggest checking with Ward County Extension agent Mike Rose to see if he knows of anyone who is a good record keeper of nature's patterns of behavior. What you are asking for is the science of phenology which is the study of such natural phenomena as blooming time, fruit set, migrating birds, etc. I know in the old days gardeners took great pride in such record keeping. I don't know of anyone that does today. It seems life is too busy for all of us.

Q: I have a spider plant. Is it okay to cut baby spiders off the runners and grow them in water? (E-mail reference)

A: It sure is. Go ahead and in no time you will have one producing spiderettes on it's own.

Q: I noticed on your Web site that you seem to be the answer man for cottonwood questions. I was wondering if I could pester you with one. We have been lucky enough to purchase a property with several beautiful cotton-less cottonwood trees. This property also has a treeless creek. We would like to use our existing trees to populate the creek. We've read that cottonwood cuttings are easy to root and transplant - cut them in the dormant stage and plant in spring. However, we've also read that they shouldn't be planted in a pot because the roots grow so quickly. So how does the timing work? If you have to wait until spring to plant, but you can't plant them in a pot after you cut them, how do you keep them from dying? (E-mail reference)

A: Don't worry, they will grow. Just get them planted before new growth emerges in the spring by carefully knocking them out of the pot and planting them at the same depth.

Q: I have a hoya plant that appears very healthy. It keeps getting buds but they turn yellow at the early stage and drop off. I have it in a south window and do not water until the soil feels dry. I do mist it occasionally because the house seems dry in winter months. How can I keep the buds from falling? (E-mail reference)

A: I would suggest misting daily to see if that helps.

Q: I have a beautiful Hope philodendron. I have been noticing what appears to be very tiny light-colored worms around the area where the plant sits. They are usually dead by the time I notice them. Can you shed any light on the subject? (E-mail reference)

A: They could be any number of critters, but I would guess that you are looking at the remains of earwigs or centipedes. Both are organic matter feeders and do not directly cause harm to the plant. If you are concerned, you can try a solution of insecticidal soap and use it as a soak but not as a spray. Pour the soap into the potting soil around your plant. This is a harmless material to plants and warm-blooded animals when used properly, but is effective at killing off soft-body insects or their larvae (which yours may be) by dehydration.

Q: I’m hoping you can give me some information on how to redirect the growth of my jade plant. It is growing straight up but I want it to have extension/branches on it so it looks attractive. Should I pinch it here and there throughout the plant at the base of a leaf? Will that start new growth? (E-mail reference)

A: You have the right idea, basically. Go ahead and make pruning nips at the tip of the plant, back to a leaf or stem. This will force new lateral growth to develop giving you more of a bushy plant.

Q: My jade plant has what looks like spots of mold on it. They are white, powdery, flat, round spots, about a half-inch diameter or smaller. Some have darker, greyish spots in the middle with a white outer ring. They appear on the leaves and where the leaves join the stems. I've looked the plant over for insects but haven't found any. However, I'm not sure what to look for. Could you tell me how to treat the plant and what conditions caused the problem? I don't think I over-water but I have been using a plant food. (E-mail reference)

A: It is unlikely that your jade has mold unless the humidity is very high where the plant is kept. I would then think more in terms of a scale problem. I suggest getting some insecticidal soap and soaking a cloth with it then, with rubber gloves on, wiping the leaves with it to remove whatever it is on the leaf. If the infestation is too extensive to do this, then you need to resort to a systemic insecticide that will take care of the scale problem. But first, take a leaf to a local nursery, florist or your county extension agent to have an accurate diagnosis made and proceed from there.

Q: Our 8-week-old golden retriever puppy won't stop eating the leaves off my very old jade plant. Are the leaves poisonous? Is there anything that I might be able to put on the leaves to get our new little biter to stop eating them? (E-mail reference)

A: Jade foliage is not poisonous but I don't recommend it as a steady diet for the pup. You can purchase some already prepped hot pepper spray. Even if you apply if just once, I can guarantee results! It also works to discourage outside nibblers as well.

Do you have a gardening or houseplant question? Write to Hortiscope, Box 5051, NDSU Extension Service, Fargo, ND 58105 or e-mail to Ron Smith at ronsmith@ndsuext.nodak.edu. Note to e-mail correspondents: please identify your location (city and state) for most accurate recommendations.

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Source: Ron Smith, (701) 231-8161, ronsmith@ndsuext.nodak.edu
Editor: Rich Mattern, (701) 231-6136, richard.mattern@ndsu.nodak.edu