Roses are great! And they can drive you crazy! Some summers, you go all season without any problems and others it just seems like one after another.  Despite the challenge growing healthy roses may present, millions of gardeners participate enthusiastically year after year. And this has gone on for centuries, because they are worth it. Nothing else in the garden matches the beauty and elegance of the Queen of the Flowers.

Are there any roses that won't be bothered by insects and diseases? There are varieties that are very resistant to problems, and others that sustain very little damage. As a group, species roses and hardy shrub roses tend to have fewer problems. Be watchful with all roses so that you can avoid or minimize problems.

Are there any cultural practices I can use to help avoid these problems? Actually, you have a great deal of control over problems with your roses. First, plant them in the right place and in the right soil. Once planted, mulch and avoid spraying water on the leaves. Then be watchful. With roses, an ounce of prevention is worth much more than a pound of cure.

I am bothered by all the chemicals sold for roses. Is there a safer way to deal with rose pests? There are several organic, environmentally safer products available. Insecticidal soap, pyrethrum and pesticidal oil will take care of the vast majority of insect problems and plain elemental sulfur is a good fungicide.

I've heard about using baking soda and horticultural oil. Does it work? There are many tests and field trials being done with baking soda and oil and some of the preliminary results are very promising. Oil has been used for ages as a pesticide and the new oils are so pure that they can be used year around without damage. It is also commonly used as a spray adjuvant, helping whatever you are spraying to stick to the foliage longer. Baking soda is being tested as a fungicide. The combination of horticultural oil and baking soda (a tablespoon of each per gallon of water) seems to be an effective way to minimize black spot and powdery mildew on many roses.

What are the most common rose diseases? Black spot and powdery mildew account for the vast majority of disease problems with roses, and you might have an occasional problem with canker or rust.

When I find a few black spots or powdery mildew, can I still treat the plant, or is it too late? Not necessarily. These are both caused by a fungus and fungicides are most effective as preventatives. Remove any diseased leaves and be especially careful to avoid getting the foliage wet. If you notice either of these problems early, routine spraying will probably prevent their spread.

What will happen if I just let the disease go? Roses that are suffering from diseases go into a steady decline, often ending the season with a pitiful handful of leaves. Since both black spot and powdery mildew carry over in the soil, if you just let it go, you have almost guaranteed that your roses will suffer again next season. These cumulative stresses will eventually kill the plants.

Is there a way to treat the soil? When you use a broad spectrum fungicide on the soil, you will minimize the harmful fungus… but you will also kill many beneficial fungi that contribute to the health of your soil and your plants. It is important to clean up any infected leaves as they fall and remove them from the area and keep the soil mulched to minimize dirt splashing up onto the leaves.

How can I identify aphids? What kind of damage do they do? What can I do about them? Aphids are the most common rose pest. They are soft-bodied pear-shaped insects that line up along the most tender buds and leaves. They are sucking insects. Aphids are vulnerable to almost all insecticides. Start by washing most of them off, then treat the few that remain. Watch closely to keep them from taking over.

Are rose slugs different from regular slugs? They are actually the larvae of a type of sawfly and can do a lot of damage very quickly, sometimes eating chunks of leaves away, sometimes skeletonizing them. Rose dust seems to be the most effective, since it stays on the leaves. They are hard to see, so hand-picking is difficult.

Big pieces of the leaves are missing on my rose bushes. What is happening? In our area, when parts of leaves are missing, it is usually a caterpillar of some type. Look over the plant carefully and you might find the culprit hiding under a leaf or laying along the stem, often the same color as the leaves. If the missing bit is almost perfectly rounded, it could be leaf-cutter bees. They take pieces the size of a dime to their nests.

Sometimes my leaves look like the only part left is the skeleton. What is happening and what can I do?
There are a few pests that seem to eat the green out of each leaf, leaving just the veins. Dusts or systemics that stay on the leaves are usually the most effective.

If my rose buds open and have little brown lines on the petal, what is going on? That sounds like thrips. They like to get into the flower buds and cause speckling, lines and sometimes deform whole flowers. Remove infested blooms and spray several times with a pyrethrum, horticultural oil or Malathion - or use a systemic such as Orthene.