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Q. I am
growing eggplant for the first time this year. The transplants seem
to be growing well, but the leaves are full of tiny holes. I see
small black bugs that jump away when I get near them. What are these
bugs
and how do I control them?
A. The eggplant
flea beetle (Epitrix fuscula) is one of the most common pests
of eggplant. Other species of flea beetles also feed on cole crops
(cabbage, broccoli, cauliflower, etc.), potatoes and sweet corn.
High populations of these pests can slow development of transplants
and severely limit photosynthesis by destroying the foliage, which
in turn reduces the yield from infested plants.
Flea beetles are small black or brown beetles with hard shells. They
jump like fleas when disturbed. Adults overwinter in the soil and on
plant debris. They emerge in spring and feed on weeds until
vegetable garden crops are planted. After feeding briefly, they lay
their eggs in the soil.
Eggplant
Tiny gray grubs hatch in two or three weeks and feed on susceptible
plant roots and the surface of the leaves. Then they pupate in the
soil and hatch out as adults. Adult flea beetles may feed for two
months. The numerous tiny holes in the leaves are characteristic of
adult feeding.
Cultural controls include good weed control in and around the
vegetable garden. This removes a nearby alternate food source for
the overwintering adults until garden transplants are planted in the
garden. Good garden sanitation -- the prompt removal of annual
vegetable plants at the end of the growing season -- also helps
eliminate overwintering sites.
Flea beetles are much more damaging to young transplants than more
mature plants. If you can protect the young plants until they start
producing fruit, you should get a good yield.
If you practice crop rotation, you can exclude the adults from
susceptible crops with floating row covers (Reemay, Garden Blanket).
Plant the transplants, and then cover with the floating row cover.
Leave enough excess fabric to allow room for the plants to grow.
Then seal the edges with soil.
Once the plants are half-grown and start to bloom, you will have to
remove the covers to allow bees and other pollinators to work. At
that point, see how large a population of flea beetles is active on
them. If there aren't many, the plants can probably live with them.
Otherwise, begin protecting them with insecticide applications. You
may also wish to try a newer product called Surround (kaolin clay).
This is a particle film that is sprayed on plants and protects them
by creating a physical barrier to pest feeding and egg-laying. You
can use it instead of row covers or begin using it once you remove
the row covers.
Surround is a thick material and works best with sprayers that have
mechanical agitation to keep the clay particles in solution. You may
find that it clogs conventional pump sprayers.
Insecticides labeled to control flea beetles include a combination
of the botanical insecticides rotenone and pyrethrins as well as
Sevin (carbaryl). Some formulations of neem (azadirachtin) may also
be effective.
Blossom End Rot on Tomatoes
Whitefly control with
insecticidal soap
Gardening
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