Opinion

IN THE GARDEN: Sap-sucking scale insects thrive on plants overwintering indoors

Q: I am attempting to send you a picture of my angels trumpet after I took it inside. All the leaves fell off, and a white mold-looking substance started to form. One trunk put on new leaves and the "mold" took over, and now the new leaves are falling off. Can you give me any advice?

A: Wow, that is an impressive display of what appears to be a scale infestation -- an insect that attaches itself to the plant and sucks out the sap. Cut the plant back at the top where it is more heavily covered, throwing away all that you prune off. Move the plant into your garage if you have one. You want to keep it as cool as possible without a hard freeze. Brugmansia (angels trumpet) can survive light freezes, but the plant will freeze to the ground and come back from the root system. Since you have moved it indoors, it would not do well outside now. But inside, in a warm home, the insects will build up more quickly. On a mild day, move the plant outside and spray it with a dormant oil or Neem oil, thoroughly covering the plant to smother out the insects. You can also find houseplant spikes that contain a fertilizer and an insecticide, which will also help. Monitor the new growth to make sure it is clean. Also, check any houseplants that are close to this one, as scale can attack a wide range of plants.

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Q: My sweet olive looks terrible [the reader sent a photo]. The leaves have turned an ugly gray/brown color, and now they are all falling off. I hope it is weather related.

A: A lot of plants look terrible, including sweet olive, loropetalum, rosemary, azaleas, gardenias and more. Temperatures hit record lows in December, and even covering them didn't help. For now, try to ignore it. If you prune now, you expose even more of the plant to potential damage. We are just getting started with winter, and who knows what we have to come? Let's hope we don't get a repeat of the recent brutal cold, but let all plants stay the way they are until spring arrives and we can assess what is dead and what is burned.

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Q: I was expecting to see some damage on my gardenias because I know they can get hurt with cold weather, but you should see my pansies. I have never had them freeze to death before, and they look hideous. Even that year we had 15 inches of snow, they pulled through. Is there any chance they can come back, or should I pull them up now? I am not going to have any color this winter any all.

A: Again, you are not alone. My pansies look pretty ragged too, but some might pull through. The flowering kale and cabbage are long gone. We got colder than we normally do, plus the cold lasted for days. Snow is actually a good insulator and protected the plants, which is why they bounced back. Many gardeners may be looking for some quick color as we get nearer to spring, but don't plant heat-loving annuals until April, at the earliest.

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Q: We bought a new lake house this year, and the previous owners planted Bradford pears in the back yard. They are gorgeous trees, but they block our view of the lake. How high up can I prune the limbs without killing them, to allow for a better sight line to the water? And when should I do it?

A: I know many gardeners love Bradford pear trees for their spring blooms and their red fall color, but they are not a favorite tree of mine, since the birds eat the fruit and drop the seeds everywhere. There are seedling pear trees blanketing our state now. I would remove them and plant something else. To answer your question, limbing them up will not kill the tree, but it can make it structurally unsound and not very aesthetically appealing. Bradford pear trees are prized for their perfect teardrop shape. This shape alone causes them to be somewhat top-heavy and therefore prone to storm damage. Limbing them up would cause them to be even more top-heavy, and could ruin their shape, creating an eyesore in the garden.

Retired after 38 years with the University of Arkansas Cooperative Extension Service, Janet Carson ranks among Arkansas' best known horticulture experts. Her blog is at arkansasonline.com/planitjanet. Write to her at P.O. Box 2221, Little Rock, AR 72203 or email jcarson@arkansasonline.com

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