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Ron Smith answers questions about plants, trees and gardens.

By Ron Smith, Horticulturist

NDSU Extension Service

Q: My ponderosa pine tree is behaving funny. In the last e-mail you sent me, you said the tree has a self-pruning mechanism to make it more majestic. When this mechanism is in effect, does the tree lose all its green needles? It looks like the tree is dying. The lower branches are green, but don’t have needles. I’ve had some tree experts look it, but they are familiar with Missouri trees and not Pacific Northwest varieties. Will the tree loose all its needles? I have a wisteria bush that blooms every year with clusters of purple blooms. I have looked on the Web, but cannot find if there are different colors. My wife was wondering if wisteria come in varieties that are pink, red or other variations. (e-mail reference)

A: I'm surprised that the local arborists don't know much about ponderosa pines. While it is not native to Missouri, the Elsbury Plant Materials Center in Missouri has given the ponderosa pine a good rating in some evaluation studies. When I referred to the ponderosa pine as being self- pruning, it means that the lower branches gradually die, which leaves the tree with a nonsymmetrical form of growth. Some find it attractive (me), while others are unhappy with any pine or spruce that does not retain the inverted ice cream cone shape as it ages. Mature, freestanding trees typically have a good “head” of growth with a dramatic and attractive bare trunk leading up to that growth. I’ve had two growing in my backyard for more than two decades and love the way they are maturing so gracefully. As for the wisteria vine, there are more colors than the typical purple. For example, rosea is a deep, rosy pink. Alba has, of course, white flowers and there are many variations in between. If local nurseries don't carry them, then scan the catalogs that should be clogging mailboxes very soon.

Q: I have browning tips on my spider plant, but I have been trimming the tips since getting the plant. Is that OK or will trimming hurt the plant? Also, the plant produced a spiderette that I pinned to some soil in a small pot to let it root while attached to the mother plant. Both started growing very fast. About two weeks later, I cut the runner. Since doing that, neither plant has grown much. The mother plant has produced one more baby, but it has taken a long time and it is very small. The brown tips have gotten worse and both plants have leaves that have blanched and dried up until they fall off. The baby plant has three tiny leaves left. Both plants are situated in a bay window in my Utah office. It is winter now, so I am wondering if they stopped growing because of the short days we have at this time of year. Also, I just repotted the mother plant prior to taking the baby because it was in a small cup. Could this repotting be the cause of the mother plant’s lack of growth? Perhaps I just need to wait for the plant to become pot bound. Unfortunately, I repotted the plant in a pot that does not have holes for drainage. However, I did put some rocks (about the size of large marbles) on the bottom of the pot. Should I repot the plant or drill holes in the bottom of its pot? (e-mail reference)

A: A spider plant is easy to grow. It can withstand abuse, benign neglect and outright mistreatment. The water you are using probably is high in soluble salts or is softened artificially with a sodium-based softener salt. Cutting the brown tips back will not solve the problem because the fresh cuts will turn brown again. There are several courses of action that I would suggest. Repot the plant in a free-draining pot or drill holes in the present one. The better option would be to repot, but don't put any stones in the bottom of the pot. Use distilled or reverse-osmosis water. Give the plant water when the soil is dry to the touch. During the winter months, most houseplants succumb to either too much water or not enough light. In most cases, both of these problems exist, but the owner doesn't realize it until it is too late. I also would advise getting a plant light. Have it hooked up to a timer so you can allow the plant to get 12 to 13 hours of light every day. This will help improve the condition of the plant in a relatively short time. When summer or the threat of frosty weather is past, set both plants outdoors under a tree or on the north side of the house. Water once a week when nature doesn't do the job. This also will do a lot to boost the plant's appearance, and stimulate new growth and the production of more offspring.

Q: After we built our house 25 years ago, we planted blue rug junipers in different places around the house. There now are numerous large branches, so we want to prune some out. Also, we have three walls over which the junipers drape, but there is a lot of old plant in them. How can we prune them and enhance the growth over the walls? (e-mail reference)

A: The junipers can be pruned to encourage new growth. Just don't leave a bare stub. Prune to where any evidence of green foliage is present. This will stimulate new growth. Regular pruning is recommended to keep these plants looking their best and to minimize old, open woody stems that may develop.

Q: I have six acres in northeastern Washington state with no trees. I would like to start a bunch of quaking aspen or similar fast-growing trees for future firewood, wind protection and their beauty. I also would plant other types of pine trees. (e-mail reference)

A: Aspens are known as a recovery species because of their temporary rapid growth. Aspens eventually give way to the species indigenous to that particular ecosystem. I would encourage you to contact the Forestry Department in your state to see if it can provide you with more suggestions.

Q: Can you settle an argument between my wife and me? She says you need to add lime to the soil to make it more alkaline. I say you need to add sulfur. Which is it? (e-mail reference)

A: When are husbands going to realize that their wives are always right? Lime does increase the alkalinity of soil that is acidic or neutral. Sulfur increases the acidity of the soil when it is neutral or alkaline. The alkalinity of the soil is measured by the pH scale, with any readings above neutral (pH 7) being increasingly alkaline. In such soil, the hydroxyl ions outnumber the hydrogen ions coming from a high calcium/magnesium concentration in the parent soil. Buy her flowers, candy, take her out to dinner or simply admit she was right. My wife just loves that when I have to admit she is right.

Q: Some time ago, I asked for help in locating an apple that old timers called the sheep nose apple. Some of your readers replied on what they believe it is. I am afraid none of them were correct, at least in regard to the apple I am searching for. I have a huge, ancient tree in my orchard that is the sheep nose apple I am searching for. From what I have discovered, the sheep nose was at one time very popular in German/Russian communities and no doubt was brought to this country from Russia. The fruit is small, golf ball size and yellow. It ripens in late July and is very sweet and mealy. The fruits are pointed on the end like a sheep's nose. I have not been able to graft a new tree from the old one. Can anyone out there help me? I would like to get some new trees started before this one dies. (Freeman, S.D.)

A: One more try! Go to for information.

Q: We inherited a pear tree when we moved to this house in 2007. That year, we had too many pears to cope with! However, we had a very small crop in 2008. We have noticed a large lump on the trunk. It looks like a fungus and is pale green in color. I've looked at several Web sites and can't work out whether it's lichen or fungus. It may be lichen because it comes off in little lumps like soft popcorn and is white and brown underneath. Whatever it is, it seems to affect the yield. Any advice on what it might be and a possible treatment? (England)

A: Fruit trees will go through alternate cycles of bearing heavy fruit one year and light the next. The growth you have described could be a fungus or lichen. I could make a better determination if you would send me a digital picture.

Q: I hate to see my beautiful coleus and geranium plants freeze, so I bring them into the basement by my three big windows. I keep them in their original pots and keep them watered. However, by November, their leaves are drying up and dropping off. The coleus plants slowly die. The geraniums usually lose their leaves, too, but grow new ones and survive. I’m wondering why the coleus plants die. (Medina, N.D.)

A: The reasons for the demise of the coleus plants are many. Some examples are a drier atmospheric humidity, lower light intensity and shorter light duration. Coleus can be grown indoors, but the right conditions for their survival must be met. You need artificial plant lighting for 12 or more hours a day and need to mist the plants with distilled water once the heating system for the house kicks in for the season.

Q: I have a rather large dieffenbachia that snapped at the base as it tipped over. The plant is very healthy, but has a leafless stalk of more than 20 inches. However, it has 30-plus inches of large, amazing leaves. It happened two days ago. The top of the plant is in water and the base is broken at the soil line. I inherited this plant from my sister two years ago, so I am very attached to it. Is there a way to save it? (e-mail reference)

A: You probably will get some new growth emerging from the broken stump in a few weeks. Keep it watered as you normally would. After the soil dries, don't try to push it by overwatering or fertilizing. With the leafless stalk, cut it into 4- or 5-inch pieces. Lay them horizontally in a flat using moist sphagnum peat moss. Cover most, but not all of the pieces. In about four to six weeks, you should see some leaves emerging from the top of the cut growing up from the peat moss and some roots should be visible growing in the peat. When the leaves have expanded and the roots are about as long as the cutting, gently lift them out of the peat and pot them. In about a month and a half or so, you should have several plants to enjoy or give away to family and friends. For more details on this and other propagation techniques for homeowners, go to

NDSU Agriculture Communication

Source:Ron Smith, (701) 231-8161,
Editor:Rich Mattern, (701) 231-6136,
Prairie Fare: Prairie Fare: 5 Tips to Evaluate Health Information in a High-tech World  (2019-05-16)  Reliability and trustworthy information is important when making health decisions.  FULL STORY
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