By Roy Lee Carter
County Extension Director
As summer approaches, the preparation and care you’ve given your vegetable garden will really be put to the test. We say this because insect problems at this time of year can be quite serious. Summer in our area of the state provides the heat and humidity on which insect thrive. Without adequate control, pests can destroy your garden.
Very soon, all the time and effort you’ve put into your garden should begin to pay off in delicious fresh vegetables that is, if you can’t get to your crops before the insect do. All the care you’ve given your vegetable garden up till now will be meaningless if insect are allowed to rob you of your harvest. We’ll talk about the most common and bothersome bugs you may find on your vegetables. We’ll offer some advice on their control. My information on controlling garden insect was provided by Susan E. Webb, Associate Professor, Entomology and Nematology, Institute of Food and Agricultural Science, University of Florida.
The insects you need to worry about in the weeks ahead are divided into two broad categories, those which live and do their damage above ground and those which live in the soil and bother the roots and lower stem of vegetables. The most common above ground pests include leaf miners, armyworms, spider mites, flea beetles aphids, whitefly leaf footed plant bug, bean leaf rollers and stinkbugs. Cutworms, wireworms and mole crickets top the list of below ground villains. Leaf miners seem to cause the greatest damage on tomato and cucumber plants. They’re called leaf miners because they burrow in between the transparent membranes on the top and bottom surfaces of the leaves as they feed. They eat the living plant tissue, leaving the membranes, which then look like tiny window panes.
The army worm - you’ll find in your garden are the same as those you’re probably all too familiar with in your lawn. They feed on plant foliage and attack a variety of crops.
Spider mites - aren’t really insects. In fact, as the name suggest, they’re actually more closely related to spiders. They’re tine pests usually no more than a fiftieth of an inch long. They gather on the undersides of plant leaves, and feed by piercing the leaves with their needle-like mouthparts and sucking out the plant juices.
Aphids – sometimes called plant lice also causes damage by piercing leaf tissue and sucking out the plant juices. Flea beetles are chewing insects which cause damage by chewing small holes in vegetables leaves.
Bean leaf rollers – The bean leaf roller feeds on members of the bean family. The adult, a skipper butterfly, deposits eggs on the lower leaf surface, either singly or in cluster of 2 to 6. The caterpillar cut triangles or semicircles from the edges of the plant leaf and fold them over to make individual shelters, only at night to feed.
Flea beetle – are tiny (1/16 inch long) bronze, black or brown beetles which attack young tomato plants, peppers, egg plants and other garden plants. They can jump rapidly for great distances when approached and they resemble large “fleas” in appearance and habit.
Leaf footed plant bugs – gets its name from the appearance of its hind legs which are large and flattened in a leaf-like shape near the feet it is generally dark or chestnut brown with a cross bar about halfway down its body.
Whitefly – the most common whitefly found on Florida vegetables is called the sliver leaf whitefly because of the effect its feeding has on squash leaves. Feeding by the immature stages or nymphs can also result in white areas in tomato fruits, streaking of pepper fruit, and blanching of broccoli stems. Whiteflies are not flies, but distant relatives of aphids and leaf hoppers and like them, feed on plant sap with piercing-sucking mouthparts.
Stinkbugs – are common pests of most all plants and are generally solitary feeders in the adult stage. Immature nymphs, which do not fly, may be found in groups. All stinkbugs give off a characteristic foul smell as a defensive weapon when disturbed.
All this may sound discouraging. But, fortunately, it’s actually fairly easy and inexpensive to control your local County Extension Office or Garden Center for recommended insecticides to control foliage feeding pests.
The insects which live in the soil are a different matter, because it’s hard to reach them with sprays.
Cutworms simply cut young vegetable plants off at the soil surface. Mole crickets tunnel through the soil in the root zone, feeding on the roots and disturbing the surrounding earth. Wireworms attack a wide variety of vegetables. Living deep in the soil, they move up quickly to attack seeds or young plants. Wireworms drill holes in the seeds and feed inside them or they bore into the taproot of the plant. Insects in this category are best controlled with insecticide baits, which are normally available at garden centers.
One thing we don’t want to do is encourage you to use pesticides if you really don’t need to. While a preventative spray program might be essential in a large scale commercial operation, you can usually deal with insects in the backyard garden on an “as needed” basis.
For more information on garden insects contact the Gulf County Extension Service at 639-3200 or visit our website: http://gulf.ifas.ufl.edu or www.http://edis.ifas.ufl.edu and see Publication ENY 476 and ENY 012