of Rhode Island GreenShare Factsheets
Insects in the Garden
insects that feed upon or parasitize garden pest insects include
lady beetles ('lady bugs'), lacewings,
minute pirate bugs, stink bugs, assassin bugs, hover flies, paper
wasps and many kinds of parasitic wasps. Flowers provide these insects
with important resources:
- the sugar
in nectar is used as fuel for searching for prey, mating and egg-laying
- the protein
and fats in pollen are used to support egg development
- the flower
is used as a place to locate mates
- small prey
that live in flowers, such as thrips, are a food source for immature
insects are vagabonds which are always in search of prey. Flowers
will attract beneficial insects to your garden, nourish them, and
induce them to search your garden for pest insects. Planting flowers
will increase the likelihood that beneficial insects will colonize
your garden and lay many eggs on your garden plants. After hatching,
their young will crawl around the garden plants and feed upon pest
insects such as aphids, caterpillars,
leaf beetle larva, thrips, spider mites and whiteflies.
that are most useful for supporting beneficial insects have small
flowers with exposed nectar and pollen. Umbels, such as coriader
(cilantro), dill (especially 'Bouquet' variety), fennel and caraway
are very attractive to beneficial insects. Alyssum, flowering buckwheat,
black-eyed susans, dwarf sunflowers and yarrow also attract these
to ten percent of your garden space to growing flowers for beneficial
insects. The plants don't have to be massed to be effective, instead
they can be tucked away in odd corners. Plant a succession of flowers
to attract and support beneficial insects throughout the growing
season--avoid gaps without flowers as this will disrupt the colonization
process. Most of these annuals will flower six to eight weeks after
germination, so it is a good idea to plant a small batch of seeds
every three or four weeks to ensure that flowers are available throughout
the growing season. Removing spent ('deadheading') flowers will
extend the flowering period of individual plants. Avoid coriander
(cilantro) varieties that are slow to bolt, as these take longer
to flower. Buckwheat will flower as soon as three weeks after planting.
Consider planting alyssum along the border of your vegetable garden
in early spring.
coriander, dill, yarrow, buckwheat
coriander, fennel, dill, caraway, black-eyed susans, yarrow, dwarf
coriander, dill, black-eyed susans, dwarf sunflowers
buckwheat, dwarf sunflowers
Joseph M. Patt, Department of Biological Sciences, Rowan University,
are poisonous! Read and follow all safety precautions on labels.
Handle carefully and store in original containers out of reach
of children, pets or livestock. Dispose of empty containers
immediately, in a safe manner and place. Pesticides should never
be stored with foods or in areas where people eat.
When trade names are used for identification, no product endorsement
is implied, nor is discrimination intended against similar materials.
Be sure that the pesticide you intend to use is registered for
the state of use.
The user of this information assumes all risk for personal injury
or property damage.
information, call the URI CE Gardening and Food Safety Hotline
at 1-800-448-1011 or (401)874-2929 from outside Rhode Island;
Monday-Thursday between 9 am and 2 pm.
of Rhode Island Cooperative Extension provides equal program