Q What's your opinion on ostrich fern as a garden plant in central Arkansas? Some people tell me that it is too warm and humid in the summer for it to be easily grown here.
A Ostrich fern is not drought-tolerant, but if planted in the shade in a rich, well-amended soil, and watered when dry, it can survive the summer. It is doing quite well so far this year. It is not the most heat-tolerant of the ferns, but I have seen it in several gardens. It doesn't grow as tall here as claimed -- maybe due to the heat.
Q Two of my clematis have a bad case of wilt. I've read that any root disturbance can cause that, and I have terrible mole problems. I kept removing diseased vines after blooming. There's nothing left of one vine now; hopefully it will come back. The other one, I began cutting it back in late winter last year and it comes back beautifully. But it's showing more wilt this summer. If I cut it back now, would it have time to regrow before frost? I'm thinking pruning might be the only way to stop the wilt.
A You can also apply a fungicide at the base of the plant after you prune it back. Clematis have been known to outgrow the wilt after several years. Large-flowered species of clematis tend to be more prone to wilt, and it is often worse in heavy soils. Normally, clematis wilt is more an irritant than a deadly disease, but if it is a continual problem, consider planting one of the smaller-flowering forms, and it should not be so troubled by the disease even in the same site. I hope you will consider planting any future plants in a slightly elevated berm to improve drainage, and amend heavy soils with compost.
Q Could you please tell me what a Bordeaux mix is?
A Bordeaux mixture is one of the oldest horticultural sprays. Used as a fungicide, it is a combination of copper sulfate, lime and water. Some folks mix their own, but it is sold as Bordeaux Mix at many nurseries.
Q Is there any sort of clip or clamp that is or can be used for air-layering plants? To hold a limb down to the ground so that it would root?
A Air layering and layering are two separate propagation techniques. Simple layering is when you take a low-hanging limb and weave it in and out of the soil. Lightly scraping the stem where it will be underground can quicken rooting. To hold it in place, simply place a rock or brick over part that touches the ground. For air layering, we lightly wound an above-ground branch and put moist peat moss or soil around the stem, wrapping it in plastic and holding that bandage in place with lightly wrapped twist ties both above and below the plastic. The plastic should keep the medium moist and allow roots to form. Once roots have formed, you can cut off the stem and have a newly rooted plant. Air layering is not as popular as layering, and you must be careful that the stem can support the added weight of moist soil.
Q Can you tell me what or where I can get information on how to stop ants from getting on my hummingbird feeders? I have tried vinegar and water. I have tried Vaseline -- you name it, I have tried.
A There are several more things you can try. You can put vegetable oil on the hanging portion of the feeder, which can make it too slippery for ants to climb. Some people hang their feeders using a really fine fishing line or set an ant trap at the top where the line is attached by smearing that area with Tanglefoot -- a very sticky substance. You will have to reapply the Tanglefoot, but ants have to crawl up to get to it, and if you hinder them, maybe they will move elsewhere.
Q I am stumped. I have planted vinca (the annual) in my flower beds for six years. The last two years I am getting dieback, losing 80 percent of what I plant. They wilt and die in a matter of two weeks. They are planted in a well-drained bed that I add potting soil to every year. All the other multitude of plants do beautifully. I've even tried a fungicide, to no avail.
A It sounds like they have stem canker. Overhead watering makes this worse. If you look closely on the stems you will see a small sunken lesion. This disease is why annual vinca or periwinkle fell out of favor for years. New varieties are more resistant to the disease, but I would plant something else in this bed for the next year or two before planting periwinkle again, since you have had it for two years.
Janet B. Carson is a horticulture specialist for the University of Arkansas Cooperative Extension Service. Write to her at 2301 S. University Ave., Little Rock, Ark. 72204 or email her at
jcarson@arkansasonline.com
HomeStyle on 07/26/2014