Become a Garden Spy

Diagnosing plant problems is like solving a "whodunnit" mystery. You need to look for clues, then add up what you have -- and haven’t -- found and piece them together. Only then can you be reasonably sure you’ve solved the mystery. It’s not always the butler (or an insect), you know!

Begin by examining the plant without touching it, looking for insects hiding in the nooks and crannies. Next, examine the leaves, both top and bottom. Look for insect and egg masses. Examine the new growth closely. Jot down some notes if you need to, so you can research the possible culprits. You might even try to collect insects you find so you can use a reference book to identify them.

It’s important to remember that NOT ALL INSECTS ARE PESTS. Ants, for example, are sometimes found on damaged plants, and are assumed to be the culprit. But they generally don’t harm plants -- they are simply there to eat the honeydew (a sugary secretion) left by the real pest, aphids.

Symptoms of disease include fuzzy spots or discolored areas on foliage, sunken or water-soaked patches on stems, and decaying roots. Some diseases cause a general decline in the plant’s health with no outward signs.

Gardeners sometimes mistake symptoms of nutritional deficiencies -- yellowing leaves, stunting, weak growth, poor production -- as signs of pests. If you see symptoms like these, consider testing your soil to rule out nutritional deficiencies and/or improper pH levels.