Roses - Insects
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  (January) Near the end of the growing season last year, a vicious insect attacked my young roses; stripping the leaves and gnawing off the ends of the canes. We sprayed and fertilized and the roses put on lots of new foliage and even bloomed again. Now I have lots of canes on these roses that have died (they have turned black) and when I break them off, they are hollow. What do I do to save the roses that are left, what did this and how do I prevent it in the future?

  A number of insects can chew on roses. Grasshoppers have been known to cause some real damage, as do several beetles and even caterpillars. It could also have been some type of animal--deer can be pretty devastating to roses. For now, leave them alone--that is extra winter protection. Late February is the time to prune them. Remove all the dead wood, and cut them back to within 6 - 18 inches from the ground. Seal the cut edges with a pruning paint or plain white glue. Sealing the cut edge prevents an insect from getting in and boring down into the cane. Hopefully, there is still life left in the roses and they will come out of it ok this spring. Fertilize when new growth begins. As to prevention of future damage, unless you can pinpoint what did it, you really can't prevent it. Monitor the plants frequently to catch the damage as quickly as you can.

  (September) I have a yellow rose bush that has little tiny black specks inside the bud if you open one up. When it blooms the bloom is deformed. The plant itself is growing and forming more buds but they all seem to be afflicted with this problem. Any ideas?

  It sounds like thrips to me. Thrips are tiny insects with rasping sucking mouthparts that feed inside the rose buds. The results are brown spots on the roses and/or deformed flowers. Once adult female thrips have ruined a rose, they lay their eggs in the damaged flower where they quickly hatch and add insult to injury. These young thrips look much like their parents except they are lighter in color and lack wings. Once they have completed their development in a week or so, they drop to the ground and complete their transformation into winged adults in the soil. The whole process from adult to adult can be completed in as few as 14 days in warm periods. Clip off and destroy the damaged flowers and clean up any debris around your roses. You can spray with Orthene, a systemic insecticide, but make sure there is ample water in the plants before spraying and avoid doing so during the hottest part of the day.

  I've just come in from checking out how my roses were progressing after their recent pruning. My climbers are doing fine, but my miniature roses in pots around my patio are in trouble. They suddenly seem to be covered with tiny little green bugs. In addition, there is a sheen on much of the new growth. What are these bugs and how can I get rid of them? As I have a two-year old who will be around these plants, I am hesitant to do a dusting. I do have some systemic fertilizer left from last year. Is it too early to apply it?

  I suspect you have aphids and they are giving off a sweet sap known as honeydew--which is causing the sheen. Aphids are easy to kill, and insecticidal soap should work fine, and not harm your child. Keep after it to get rid of them before they spread to other plants. It is time to begin protecting roses from blackspot disease which does best with the systemic. Many rosarians don’t like to use the fertilizer mixed with the systemic on a regular basis. Once or twice shouldn’t hurt, but you normally need the fertilizer monthly, and the fungicide sprays more regularly.

  As the garden season approaches, I wanted to tell you about our successful aphid treatment last summer. My daughter is in a rose phase and we planted over 20 different roses in our yard. When the weather warmed up last spring we were attacked by aphids. They were green, rusty red, white and fuzzy--all kinds, and everywhere. They were on our roses, daylilies and particularly on new buds and leaves. We sprayed with Malathion once and saw no diminution of numbers. So we began squashing them by hand. Yuck!! I remembered about lady bugs so we thought we would give it a try. We called all over town and could not find a local source, but found a catalog that will ship lady bugs for about $18. The bugs arrived in two weeks and we distributed 1800 lady bugs in the garden. The next morning I checked the plants and there were lady bugs moving everywhere, and I couldn’t find a single aphid. I thought I would share this with you. It really works.

  Ladybug beetles--both adults and larvae are voracious eaters of aphids. The most important aspect of using beneficial insects, is you must have a host insect before introducing them. You did it the right way. There are many gardeners who purchase lady bugs and distribute them before they have a pest. All this will do is populate the neighbor's yard. If there are no aphids for them to feed on, they won’t hang around.

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