If you notice leaves that appear to shrink and curl up, you may have thrips, tiny little pests that scrape tissue from your flowers and leaves and then drink the plant juices. If you get a lot of thrips in one place, flowers and leaves won't open normally and they'll look twisted or stuck together. You'll also notice small black fecal pellets that thrips deposit when they feed.

Thrips usually appear in May, but in desert areas in can be as early as March. They breed quickly, so as the season progresses, a greater number of thrips will be in force in your garden. They tend to prefer white and lighter colored rose blossoms and gladiolus leaves and flowers.

There are many natural controls for thrips, including ladybird beetles, larvae, predaceous thrips and mites.

If your thrips problem gets too serious, you can try malathion, diazinon, chlorpyrifos, or acephate. For edible plants, try malathion or insecticidal soap.