February 22, 2001

Hortiscope

Ronald C. Smith, Horticulturist
NDSU Extension Service

Q: I have an old jade plant. Some branches get weak then break off; some other branches seem to be shriveling up and dying. This also happened to a transplant of this same plant. Is there something I can do to save it? (E-mail reference)

A: Generally Jade plants suffer from too little light and too much water at this time of year. It sounds like your plant is slowly dying from root rot. I suggest taking some healthy leaves off and rooting them before the entire plant is gone.

Q: I am a long way from your location (southeast Texas), but I hope you can give me some advice about a problem I am having with my red oak trees. Recently I have noticed patches of the bark change color, usually in areas of about 10 inches by 10 inches. I can pull the bark off by hand and underneath I find what I think is hard wood. I don't think that the bark is growing back where it has come off, because the color is more like weathered wood and does not have the thickness of the original bark. I have been in this house for over 20 years and I have never seen the trees do this. Should I fertilize the trees? If so, what should I fertilize them with? Should I spray them with a fungicide? The trees are about 60 years old and have well established branches. (E-mail reference, Texas)

A: I'm willing to bet that the oak you are making reference to in your part of the country is the live oak -- Quercus virginiana. It is characteristic of this tree to develop a platy, alligator-type bark with age that fits your description. Some exfoliation is common with fluctuations of moisture and temperature. Generally the leaf color and density is a good indicator of any fertilizer need. If the internode growth (the area between the buds or leaves) is shrinking, or the foliage is appearing chlorotic, then some fertilization may be called for. If there are no symptoms of disease or insect problems, I'd suggest not spraying, as to do so without overwhelming evidence would only throw nature out of balance and open the door for parasites to move in.

Q: I have a dragon tree that has lost all the leaves from being in the shop without heat. The temperature was as low as 16 degrees F, and the tips of some of the stems are soft and black. Can I do anything to save this plant? (E-mail reference)

A: Your dragon tree is toast. If it should revive from 16 degrees, let me know, and we'll clone the most cold-hardy Dracaena marginata ever known and make millions! I advise dumping it and starting over.

Q: As far as I can decipher, I have an American basswood tree. The leaves seem to be a perfect match to pictures I have found. Along with the leaves are these oar-shaped things. The flowers don't seem to emit any odor, and I have read the Basswood flowers are fragrant. It is growing close to my driveway in front of my house in southeastern Indiana. The problem is that it is very messy. There is no time during the year that it isn't dropping something -- little dried up berries, leaves, and most annoying are the twigs that fall even after the slightest breeze. The main branches grow almost vertically, but the smaller branches seem to grow downward. So, does this sound like it is a basswood? And if so, are these "healthy" characteristics? I am fed up with the thing, and am ready to have it cut down (all 100 feet of it). However, if it isn't healthy, is there something I should be doing? (E-mail reference)

A: In every way except the lack of fragrance from the flowers, it sounds like a basswood (Tilia spp.). And no, the messiness isn't normal, at least from my perspective. I love the tree so much it is hard for me to find fault with it. The only mess I have ever associated with this species is the shedding of the bracts that subtend the flowers. This usually occurs in mid summer, then the leaf drop occurs in autumn. Since your tree is so large, it is bound to have a collection of dead twigs that are going to be strewn around as a result of any winds. It sounds like you have quite the specimen tree. I'd hate to see you cut it down. Perhaps a local certified arborist or tree surgeon could come out and do some remedial pruning for you to relieve some of the frustration.

Q: My brother helps out on a horse farm on his days off. They have a lot of pine shavings mixed with manure that are really piling up. He has hauled a lot of it off the place but he would like some information on how to break down the shavings faster. Are there any commercial composting agents that would help break down the shavings? Or something else? (E-mail reference, Bozeman, Mont.)

A: What is needed is to get the "N" in the C/N ratio higher, and he can do this if he adds some commercial nitrogen to the mix, or simply collects some grass clippings from golf courses or lawn care operators who mow lawns for a living. It depends on the size of the pine shavings, too. The finer they are, the quicker they will break down. Even if they don't break down to unrecognizable components in the pile, one summer of weathering will usually do the job at rendering them ineffective in tying up available N. At that point, the end user has nothing to worry about.

Q: I am looking for information about growing rhubarb from seed. Do you have any information or suggestions? (E-mail reference, Williston, N.D.)

A: No and yes. No, I don't have any written information, and yes, my suggestion is to either have a ton of patience to grow it from seed, or simply propagate it by division. The latter is what I seriously suggest, as today's rhubarb is highly hybridized and the seed would not come true. So, if it is a particular quality that is wanted, the vegetative means is the only way to go. Otherwise, the quality will be quite variable.

Q: Can you help me with a problem I'm having with my Sansevieria plant? The leaves are "tipping over," which I read about in Hortiscope, but also when I go to put them upright they pull right out of the soil with the slightest of tugs. I've taken these "floppy" leaves out of the pot and put them in a pitcher of water in hopes of rooting them, but I'm not sure if this is the way it's done with this kind of plant. (E-mail reference, St. Louis, Mo.)

A: The "floppy" syndrome of the Sansevieria plant is due to overwatering during the winter months, causing some of the roots to rot off. Take a leaf cutting about 6 inches long from one of the "tongues," insert it in a 50:50 sand/peat mixture and allow it to develop a new individual. The cutting will not be a part of the new plant, so once the new one develops sufficiently, cut the original cutting off and repot. Alter your watering practices. During the winter the plant needs water only every two months; in the spring through autumn water moderately, allowing the media to barely dry between each watering. Avoid getting water on the crown of the plant.

Following this practice, the plant should develop a root system that should just about crack the container it is growing in! When it does become pot-bound, divide and repot.

Q: My three giant umbrella plants (over the rooftops) are now all but sticks due to the freeze here in central Florida. The lower branches and leaves are intact. Can I cut the tree down to window height (height of other branches)? I see no new growth, and the trunks are about 4 inches or more around. I have had these plants for 14 years. The last time it got down to 30 degrees, the trees came back in full bloom. This time, due to the height, I don’t think there’s much chance. It’s 80 degrees during the day now. (E-mail reference, Florida)

A: The tree should come back if you cut it to where the lower branches are -- about a quarter inch above that point. Once they get to that size it should take more than a 30-degree overnight to kill the thing off. In many cases, a freeze injury like this, coupled with a follow-up pruning like you are intending, results in a better-looking, bushier plant.

Q: I am sending a picture of a morning glory that I planted around a stump. It looked very healthy, but it never bloomed. Another lady in town also has a morning glory that didn’t bloom. What are we doing wrong? (Jamestown, N.D.)

A: Judging from the vigor of the vine and its location, I would guess that it is getting too much nitrogen, giving it all vegetative and no flowering growth.

Q: I started a three new azaleas from one plant that I had and they are all blooming profusely. What really amazes me is one of the new plants has two colors of flowers. One is the original pink and white and another is more a red-orange, almost solid. I have no other azalea plants in the house. How could this color thing happen? (Wilton, N.D)

A: It could be a somatic (non-sexual) mutation. It often happens in plants, and to keen-eyed nurserymen, this is an opportunity to introduce something new. Enjoy!

Q: I had a problem with blight in my garden last year. If I move my flowers and tomato cages to another location, do I need to worry about spreading the blight to the new site? (Pettibone, N.D.)

A: Yes, you will most likely carry the pathogens to your new site, unless you follow extremely good sanitation practices. This is possible with the cages but not likely with the plant material.

However, keep in mind that the new location may not support pathogenic activity because of better drainage, antagonistic microbes, etc. Give it a try -- it is likely to be better than the old site.

Q: I have a large garden and have had good luck in everything I planted, but the last two years the garden didn’t amount to anything. The vegetables came up good, but they didn’t grow any more. I use well water to water the garden, not city water. I have put dry leaves, mowed grass, and compost on the garden, but it didn’t seem to make a difference. Is there some kind of fertilizer I can put on? What do you suggest? (Jamestown, N.D.)

A: Start with a soil test. Send a pint of soil in a zip-lock bag, to the NDSU Soil Testing Lab - Waldron Hall, Fargo, ND 58105. I will then interpret the results and advise accordingly. Request N, P, K, OM, pH, and SS. The charge will be $20-$25 for each sample.

Q: I have two questions. I have four junipers in front of my house and have kept them trimmed and shaped to a rounded top. Last summer one started turning brown, and the county agent diagnosed it as needle blight. I sprayed with Daconil, which was recommended. Now I have noticed that the other three are also turning brown. What do you recommend that I do? My other question is, my husband is buried in a cemetery about 40 miles from where I live. I had two tall evergreens cut down from beside his grave, since the roots were growing and pushing up the monument. I need to have something else planted in that spot this spring. What would you advise? The cemetery does not allow any tree or shrub which would grow as tall again. (Jamestown, N.D.)

A: At this stage, and with no further analysis, I suggest removing the junipers. They will never look good again, so get rid of them and save yourself the aggravation. Concerning the graveside planting, I suggest daylilies. They are tough and maintenance free. Another one would be the ‘Karl Foerster’ feather reed grass. This is a beautiful ornamental that needs very little care and is not invasive. In our plantings around the state they get between 4 and 6 feet tall.

Notice to e-mail correspondents: please provide your location–city and state is sufficient–for accurate advice.

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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.

Source: Ron Smith, (701) 231-8161, ronsmith@ndsuext.nodak.edu
Editor: Gary Moran, (701) 231-7865, gmoran@ndsuext.nodak.edu