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Ron Smith answers readers' questions about the world of plants and gardening.

By Ronald C. Smith, Horticulturist NDSU Extension Service

Q: I bought an amaryllis plant about a month ago. It has long, healthy leaves, but it has not produced a new stalk or flowers. It looks like the stalk is still very small and not growing. I am not sure what I’m doing wrong. The plant gets lots of sunlight and I do not believe I am overwatering it. I have two friends who got amaryllis plants and both of them have produced flowers. Could it be that I didn't plant the bulb deep enough? Any advice at this point would be helpful. (e-mail reference)

A: It is very likely that you did not cause the problem. There is probably something genetically wrong with the bulb. I would take it back or throw it out and get another one to enjoy. Generally, once these bulbs begin producing the flower stalk, it takes a major event to keep them from producing a flower!

Q: Is it OK to reuse potting soil to repot a plant? (e-mail reference)

A: The answer is no! Always use fresh, pasteurized media for repotting. Use a new pot or one that has been thoroughly cleaned!

Q: Our Cub Scouts sold Christmas trees this season. There are a lot of pine needles that they didn't shake off before shipping. Can I use the needles as mulch or are there spores on them that could affect my plants and trees? The trees came from Oregon, if that makes a difference. (e-mail reference)

A: The needle trash can be used as mulch around your landscape plants. There is no more risk in using these needles than there would be from using needles from your own property.

Q: My indoor ficus is beautiful, but continues to leak sap. I trimmed it before the cold weather started, but I don't think that has anything to do with the sap problem. Please help. I'm getting tired of the sticky mess. (e-mail reference)

A: The sticky sap is caused by feeding insects or spider mites. Examine the plant carefully. Look for signs of webbing and white or brown scale insects attached to the stem or leaves. It is one or the other, but, in a worst-case scenario, it could be both! There are many products on the market that can provide control, if the problem population hasn't gotten out of hand. If the infestation is overwhelming the plant, then you would be better off dumping the plant and starting new. If you don’t fix the problem, the plant will die eventually.

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 at to 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: I received a cyclamen as a gift almost two years ago. This past summer, some of the leaves turned yellow, so I pulled them off. I never have allowed the plant to completely dry out (except sometimes accidentally). It has fewer leaves than it originally did, but still looks full and the plant is in its original pot. The leaves look good, but are starting to curl. Can you tell me what I should do next? (e-mail reference)

A: Since you didn’t mention it, I would suggest repotting the plant. Also, check the temperature of the room that it is in. Cyclamen like it cool, so keep it away from forced- air heating vents. Don't overwater the plant, but do keep the potting media damp. Be careful to not bury the tuber when repotting. I don't know what else to tell you. Usually, cyclamen are dumped after completing a blooming cycle.

Q: I have a dieffenbachia plant that is about 12 feet tall and appears to be quite healthy. About six months ago, I moved the plant to a larger pot to encourage more growth. It worked because there was a lot of new growth, but it has slowed considerably. I want to move to a bigger pot again. How big can I go? I want to go as big as possible without harming or killing the plant. Also, seed pods have started growing at the top. Do I cut them off? I want to keep it growing taller because I have a high ceiling. Is this a mistake? Should I cut it and grow two or three new plants? (e-mail reference)

A: Go to my Web site at: for a lot of information on dieffenbachia plants. Moving the plant into a new pot often slows the growth initially. It’s sort of a shock reaction. Moving it again this soon is not recommended. Going too big will not hurt the plant any more than a normal move would, but there is an adjustment to the watering/fertilizing that often is mismanaged. This may lead to a decline of the plant or, in many cases, cause it to die. Prune off any flower pods you see developing because it slows down vegetative growth. I detect a little impatience in your note. Persevere and persist in your care of this plant and it will reward you with the size you are wishing for.

Q: We have two Martha Washington perennial geraniums. Their stem sections are quite hardy (more like shrub stems). I’m wondering if the best way to propagate these plants is by root splitting (as in delphiniums) or whether some other technique should be used. In either case, could you please explain in detail the steps that I should take? Your help in this matter will be hugely appreciated. (e-mail reference)

A: I never have tried root splitting Martha Washington geraniums, but they root quite well from stem cuttings. The size or thickness of the cutting shouldn't negatively impact the success of this method. I encourage you to go to my publication on the Web at to read or download the details on stem cutting.

Q: We have a blue spruce we planted more than 30 years ago. It was a beautiful tree until this year. In the past few months, the spruce has started leaning to the east at a drastic angle. It almost looks like the tree is lacking afternoon sun. The west side of tree looks like it's dying because there is no green foliage except at the very top. The east, north and south sides of the tree look OK. We also have had a major mole problem this summer. We have sprayed and set out poisoned peanuts, but those solutions didn’t work. The whole yard looks like an underground turnpike. This has been the driest summer we have had in years. I root watered all of our trees except the large spruce and apple trees. I didn’t root water them because I figured they were well-established and didn’t need it. (e-mail reference)

A: Just as the biggest football players need water to keep going, so do large, well-established trees during extended periods of drought. There is probably nothing you can do about the dead side of the tree. Once that happens, it stays that way. You can save the rest of the tree by deep-root watering at least once a month. I would suspect that the soil is not frozen in your part of the country, so I would suggest laying a hose around the outer edge of the evergreen in at least three to four locations and allow the water to slowly soak into the soil. Soak the soil down to at least 12 inches. As winter departs and new growth begins, the trees will have some water to pull from the soil to supply the growth surge. As for the moles, they eat grubs and earthworms for the most part. They do not eat roots, but their burrowing activity can cause a lot of damage to the root systems of lawns and other plants. The poisoned peanuts you attempted to use are not effective against moles, but they are good against voles. In North Dakota, what some people have been blaming moles for actually is caused by voles. There is a big difference in the treatments to eliminate the two. For moles, use a product known as Thiram. It should be available at your local farm supply store. Now would be a good time to take action because they usually bear their young in a single litter in late April or May.

Q: Many years ago, I was given a large fiddle leaf fig. It did not get enough light because it was in a house we only went to on weekends. All the leaves dropped off, so it was just a potted stalk. We put the pot outside and little by little it started to grow leaves and became healthy. We moved the plant to the city, where it had lots of light. The plant thrived and became quite spectacular with huge, shiny leaves. The room has southeastern exposure and the plant was set back in the room, so it did not get direct sun. The only change that I can think of is that we put on shades to block out some of the light during the summer. The plant became unhappy and started to lose leaves. We tried repotting, but that didn't help. We moved the plant to another room that has a northern orientation, but strong, filtered light all day. We are careful not to overwater and we have given it fertilizer and nitrogen during the spring and summer months. New leaves appeared, but they are very small and sparse. Is there anything we can do? (e-mail reference)

A: It might be that the pot the plant is in is not free-draining. It’s just a guess because it sounds like you have done everything I would have suggested.

Q: I cut down a hackberry tree and am planning to burn it for firewood in my fireplace. It seems like a very hard wood. Does it burn well? (e-mail reference)

A: It is a very hard wood. If you get it burning, it will yield excellent heat units and not burn up too fast. Enjoy!

Q: I found your Web site during a search and am hoping you can give me some advice about my jade plant. It's around 15 years old. Since this summer, some of its new leaves are growing weirdly. It is as if something is gnawing on the leaves. Most of the weird leaves look chewed in the center, making the leaf a figure eight or hourglass shape. There doesn't seem to be any visible bugs crawling on it, but there is sometimes a small line of bumps or a scar on the underside of the leaves. I put the plant outside during the summer, so I am afraid it could have picked up something while out there. Thanks in advance! (e-mail reference)

A: Get a reading or magnifying glass and look closely on the stems of your plant because something apparently is enjoying them as a meal. Don't just concentrate on the newly opened leaves. Look on the underside of the older leaves and along the stems as well. It could be that you have a scale infestation that needs to be eliminated or the destruction will get worse.

Q: I bought a schefflera plant from a nursery that assured me that the lack of light in my north-facing apartment would not be a problem. After reading some of the postings on your Web site, I realize that advice was very wrong. The plant has started dropping leaves, particularly around the bottom of the stalk. Is there any hope of saving the poor guy? My kitchen has fluorescent lights, so if I put the plant in the kitchen at night with the light on, would that help? (e-mail reference)

A: The problem might be more easily solved if you simply obtained a plant light or two that you could direct on the plant. Fluorescent lighting will do the trick, but it often is too weak by the time it reaches the leaf surfaces to do much good. Schefflera is a medium light plant, which means it needs about 200 or more foot candles of light for about 12 hours a day to look its best. You can acquire these lights with timers at any discount store that handles garden supplies. What has happened to your plant is that it came from a nursery or florist that had it under optimal light conditions. When you moved it to your low-light apartment, the plant was not acclimated to this new setting, so it began dropping leaves. In a perfect world, the plant should have gone through stages of gradual light reduction that would be equal to the average light setting of an apartment in your location. During that period of acclimation, old leaves would have dropped and new ones emerged that would have been better adapted to the new environment. Since our world is less than perfect, the results are usually what you described. Plant acclimation is something that most retailers cannot afford to do because houseplant pricing is a very competitive business. These days, truckloads are harvested in places such as south Florida or south Texas. The plants are potted in the field and sent very cheaply to discount stores across the country. The plants look good initially, but many deteriorate to the point of disposal by the new owner within a few months.

NDSU Agriculture Communication

Source:Ron Smith, (701) 231-8161,
Editor:Rich Mattern, (701) 231-6136,
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