Cucumbers are vegetable plants that thrive in warm soil, so you should plant seeds after the danger of winter frost no longer causes problems. The warm soil helps seeds germinate and plants grow properly, according to University of Illinois Extension Watch Your Garden Grow. Pests attack cucumbers from the time they are young seedlings. These pests include the pickleworm – the green caterpillars inside them. Cucumbers with a pickleworm have a visible hole on their skin.
The pickleworm caterpillar thrives in warm climates like Florida, Texas and the Carolinas, but is also found in Connecticut, Massachusetts, some parts of Canada and South America. Adult moths lay small, white-colored eggs when cucumber are seedlings or in the budding stage. According to the University of Tennessee (UT) Institute of Agriculture, adult moths have a 1 1/4-inch wingspan and a large, light-colored or yellow spot in the middle of their dark wings. Once the eggs hatch, the larvae start out white with dark spots. Mature larva turn light green or a greenish yellow.
Pickleworm caterpillars damage plants during their larvae stage because they eat the growing cucumber for nutrition. The cucumber usually has a hollow center and holes that the pickleworm uses as an entrance and exit. The CropLife Foundation says cucumbers inhabited by pickleworms are inedible because the insects leave waste products as they feed on the plants. Cucumbers have to be thrown away because they spoil and rot. Pickleworms also damage the exterior, including the leaves and stems.
Insecticides aid in the prevention and reduction of cucumber damage caused by pickleworm invasions. The UT Institute of Agriculture says to use registered and approved insecticides on blossoms and buds as soon as you detect pickleworm larvae. This is a critical moment because it's too late to administer chemical treatments once the larvae enter the plant. The UT Institute of Agriculture says to follow the pre-harvest interval (PHI) on the product label, which tells you the last time you can use the product before harvest. Applying chemical insecticides in the evening reduces their toxic effects on bees.
Planting cucumbers as early in the season as possible reduces the chance of moths laying eggs in them. The UT Institute of Agriculture says covering plants with screens keeps moths away from the young seeds and blossoms, thus preventing pickleworm eggs from being laid. You must diligently monitor your cucumber plants for signs of rotten leaves, chewed blossoms and cucumbers with holes. Cut decayed parts to prevent the spread of caterpillars to the other garden plants. You can use rotten cucumbers as compost in the soil.
- Alabama Cooperative Extension System: Identifying Caterpillars in Field
- AgriLIFE Extension: Aggie Horticulture: Pickle Worm
- University of Florida Institute of Food and Agricultural Sciences: Featured Creatures: Pickleworm
- James City County/Williamsburg Master Gardeners: Pickleworm, Diaphania nitidalis
How to Sew a Caterpillar
Many children have a natural fascination with insects. Because of the popularity of Eric Carle's children's book "The Very Hungry Caterpillar," many...
Why Are There Green Caterpillars in My Yard?
Several varieties of green caterpillars appear in your landscape for a number of reasons. Some attack the leaves on shrubs, trees and...