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Ron Smith answers reader's questions about the world of plants and gardens.

By Ron Smith, Horticulturist

NDSU Extension Service

Q: We purchased a weeping fig six months ago. Two months ago, we started to see that some of the leaves have small, brown spots with small holes and the tips of the leaves are brown. A lot of the leaves started to fall off. There are some new leaves that are starting to grow, but even those have the same brown on the tip. The soil is wet and we are using Osmocote fertilizer. (e-mail reference)

A: It sounds like you are overwatering the plant or it may not be getting enough light. I suggest backing off on the watering significantly. Allow the soil to dry down to just being slightly damp 1 inch below the surface. After that, give the plant a good watering. Twenty minutes after watering, pour the water out of the saucer. If you cannot locate the plant to a higher light location, get a plant light or two and run the light for 12 hours a day to get more photosynthetic energy going in the plant. That will help the plant develop a better leaf canopy.

Q: I have what appears to be a green Braeburn apple tree. It has silver leaves and one dead branch. The fruit it produces has black spots and sometimes a reddish mold forms on the black spots. There also appears to be mold growing on the trunk and on the new shoots that are coming up around the base. (e-mail reference)

A: It doesn't sound good. I would suggest removing the tree and replanting. The suckering coming up from the base of the tree is a good indication, along with the other factors you have mentioned, that the tree is in its final stages of decline. It likely has a number of maladies, such as borers, bark beetles, stem cankers and a leaf fungus of some kind.

Q: I stumbled upon your Web site because I was looking for information on the potential medicinal value of hackberry leaves and why a dog might want to eat them. You responded that you had never heard of this before and offered a few suggestions. We have a mixed-breed dog that hunts for hackberry leaves and then eats them. Our dog has eaten all of the leaves on the lower branches. This evening the dog even resorted to standing on its hind legs to reach the last few leaves on the saplings! Just thought you might like to know that the golden retriever mentioned on your Web site is not alone. (Texas)

A: Good grief – another dog that eats hackberry leaves! I am at a loss in giving you a rational answer. While I lived in Texas, my mixed breed would eat some disgusting things, but never hackberry leaves. Thanks for adding your story to this unusual activity! Perhaps someone with a Ph.D. in animal science will let me know what attracts certain dogs to hackberry leaves.

Q: I have a China doll tree 2 meters away from the house. Will the root system damage my house? Should I remove the tree? (Adelaide, Australia)

A: Find something else to worry about. Unless your foundation leaks like a sieve, your house will not be damaged by the roots. The China doll must be a beauty to behold! In our part of the country, the only China dolls I've seen are no taller than 1 meter. Enjoy!

Q: I received a calla lily kit last March that contained the bulb and some soil that expanded when water was added. The bulb came up in a matter of days, but has yet to blossom. The plant shoots out leaves, but a lot of them get brown spots. I thought I had it too wet, so I cut back. However, it started to look stressed. I increased the amount of water again until one could barely tell that the soil was moist. I do remove the leaves with brown spots from time to time. I have the plant sitting by a south window. (e-mail reference)

A: Generally, waiting for calla and other lilies to bloom is like waiting for a baby to be born. Both will happen when they are good and ready! It sounds like you are doing all that is needed to get it to flower. Having it by a south-facing window and keeping it moist are the basics. If you don't have the patience to wait much longer, dump it and try an amaryllis.

Q: I have had my ficus for about 16 years. It is dropping leaves and looking droopy. I have not moved it and water it once a week. Do you have an idea what could be going on? (e-mail reference)

A: Based on what you have told me, no. Obviously something has changed that is causing this to happen. Usually, a root rot or vascular disease causes this to happen, but it could be from something else as well.

Q: What cultivars of grapes would you suggest for Sargent County? The client wants to use the grapes for juice and wine and, if possible, for the table. (e-mail reference)

A: For table or jelly making, try bluebell, Swenson's red or edelweiss. For wine, try frontenac, frontenac gris or La Crescent. I have some of these growing in my backyard and am looking forward to getting an initial harvest this year. We also have some growing at the Research Extension Center in Williston.

Q: Thanks for your Web site. I think it is very informative. I live in Minnesota and have a 40-year-old hoya (my mom's) that bloomed a few years ago. I've transplanted it to larger pots as it got bigger. It has a white, milky substance on the stems and leaves. I saw small, flying bugs on it, so I sprayed it to get rid of the bugs. However, spraying did not get rid of the milky substance. Otherwise, the plant seems healthy. I removed the entire plant from the soil last summer and soaked it in clean water. (e-mail reference)

A: The white, milky substance likely is powdery mildew, but it would be unusual for the plant to have it, so this is a guess. If you could send me a photo of it, I could make a better determination for you.

Q: I found your e-mail address while looking for information about an aluminum plant that I have. When the plant tries to put out new growth, most of the buds shrivel up and die. Now the older leaves have started to dry up. The plant is in a north-facing window, so I'm wondering if light might be an issue. Any advice to help save my plant would be appreciated. (Ottawa, Canada)

A: This little used or known houseplant is popular with terrarium enthusiasts. It does well with high humidity, kept evenly moist and in filtered, strong light. From your description, my best guess is that the plant is probably falling short of getting enough light and humidity. Get a plant light and use it daily for 12-hour periods. Mist it on a regular basis using distilled water. This should help the plant recover.

Q: I have a spruce tree that I bought at a Christmas tree lot. We set it up in water on Dec. 9. We decorated the tree with the usual decorations, such as lights, balls and tinsel. We watered the tree twice a day. As I was taking off the decorations, I noticed the tree has new growth along the branches. It has a brown covering with very green buds underneath. The tree is covered with new growth. Is this possible? I thought a tree dies after it is cut. I have had spruce trees at Christmas for more than 60 years, but don't recall ever seeing new growth. (e-mail reference)

A: Don't be perplexed. The tree is coming out of dormancy because of the mild temperatures and the consistent water regime you followed. This also is a good indicator that your tree was cut within a week or so of your purchase and kept in cold temperatures before you started giving it some decent care. Eventually, the buds will die because the tree lacks a root system to continually provide moisture and nutrients to sustain it. The brown covers are there as protectors of the viable tissue beneath.

Q: I am losing my devil's ivy. I repotted the ivy in a very large pot so I wouldn’t have to do it again for many years. All the leaves turned yellow and brown and are dropping off. The main stem is green. Can you help me bring it back to life? (e-mail reference)

A: Usually overpotting results in overwatering. You may be watering the same number of times as you did previously. However, with a larger soil volume, the water is retained longer. The continuous watering causes the plant to decline in quality, which leads to the gradual death of the plant. My advice is to back off on the watering significantly. Water when the soil is dry after inserting your index finger about an inch into the soil.

Q: I have a palm houseplant that has very weak new growth. There are brownish growths or bugs on the stem. They crumble when I touch them. Is this a fungus or a bug? How can I fix it? (e-mail reference)

A: Based on the limited information you provided me, my best guess is that the plant is not getting enough light. As for the brownish growth, it probably is residual material from a fungal organism. I think that if you provide more light by moving it to a sunnier location or providing direct light using a plant light or two, both problems may be solved.

Q: I enjoy reading your column every week. I have a question about morning glories. For many years, I have planted morning glory seeds along the south side of our house between the garage and sidewalk. We have chicken wire on the garage, so the plants grow beautifully to the top of the garage and fill in the whole side. This year, I started the seeds indoors in April and transplanted them in May. However, no flowers developed on the vines. All the other years the garage was covered with blue flowers. Do morning glories use up all the nutrients in the soil through the years? Should I rotate crops the way farmers do? I usually add a little bit of fertilizer (12-12-12) to the soil each spring before planting. Could I have had a bad batch of seeds or was it a bad growing year for flowers? I called former NDSU Extension Service agent Dave DeCock on his radio show. He said that I overwatered the plants and took too good care of them, so that is why the vines grew without flowering. I usually don't water the vines more than once a week, but it was so dry last summer, so I watered more. (Jamestown, N.D.)

A: What Dave said is correct. Too much good care will spoil the plants to the extent that they will not go into their reproductive cycle. However, from what you have described, it doesn't sound like you did, so I'm at a loss as to why the vines didn't flower. It could be that something changed in the environment, such as a shading change, construction debris or nitrogen migrating in from somewhere. It was a very good year for flowers and morning glories in particular. The morning glories we planted bloomed profusely and even attracted hummingbirds! I wouldn't give up on growing them. This probably was a fluke of some kind.

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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