Pesticide
Free Gardening
Yes,
you can garden without using pesticides... and it's becoming more important
than ever, as the insects are developing immunity to the chemicals used most
frequently.
Here
are some alternatives to using pesticides
in your home garden or orchard.
Cultural
Controls
PROMOTION
OF HEALTHY PLANT GROWTH: Plants stressed by poor nutrition or inadequate water
are more susceptible to pests and diseases.
Fertilization and watering should be moderate but consistent, thereby
avoiding sudden changes in growing conditions.
USE
PEST-FREE PLANTING MATERIALS: Carefully check plants for pests and
diseases before purchasing. Buy plants
from reputable nurseries. Cheap deals on
nursery plants often are no bargain.
USE
ADAPTED, PEST-RESISTANT VARIETIES: Some plants have been bred specifically to
resist plant diseases, or insects. Some
varieties are bred to better tolerate the effects of weather or garden
conditions. Always choose types of
plants that are adapted to local conditions.
PLANTING
SITE PREPARATION: Minimize injury to new seedlings from pests and diseases by
making sure the soil crust is broken up and/or amended; and temperatures are
warm enough (50 to 60 for warm-season plants); Make sure that planting holes
for trees are the proper width and depth.
FERTILIZATION:
Many
pest problems can be minimized if plants are healthy and vigorous. Give them the proper balance of available
nutrients. Know when to fertilize and
how much. Test soil periodically and
correct nutrient balance.
CROP
ROTATION: Disease problems tend to intensify when related plants are
repeatedly planted in the same soil, allowing disease organisms to thrive
there. They can survive in plant debris
and produce resistant stages that persist for years in the soil. Rotation to non-susceptible crops can stop
the development of the disease organism and, ultimately, allow it to die out.
SANITATION:
Many
problems can be alleviated by a good cleanup program. Remove and promptly dispose of dead and
diseased limbs or infested plants. Control
weeds before they reseed. Discourage
pests in compost piles through proper maintenance.
TILLAGE:
Turning
the soil improves it. By incorporating
old plant materials, the soil cover prevents many fungi and bacteria from
spreading. Many fungi that cause plant
disease survive in intact crop debris but are killed when it decomposes.
WATERING: Drip irrigation or spot watering
prevents weed germination, saves water and controls fungal and bacterial. However, if you have problems with thrips1
spider mites and cabbage worms, hosing and overhead irrigation is
advisable Caution: Water on the leaves of roses leads to mildew.
Mechanical
and Physical Controls
BARRIERS: Use cardboard collars, floating
row covers, sticky materials and diatomaceous earth to detour pests.
MULCHING:
Control
weeds, warm seed beds, and conserve water with mulches.
SOLAR
HEATING (5olarization): Some weed seeds and disease producing fungi can be
eliminated with solarization. Prepare
garden site; moisten soil; Cover area with thin polyethylene sheeting for four
to six weeks. Temperatures must be very
high for this to be effective here.
HOSING/SYRINGING:
Many
insect and mite pests can be controlled by forcefully hosing (syringing) plants
with water.
HANDPICKING:
Remove
harmful bugs, beetles, caterpillars, and their egg masses by hand. Hard scales can be rubbed off the plants with
a plastic scrub pad. Vacuuming is also
an option.
HOEING,
TILLING: Weeds
are easiest to restrain when they are young.
Hoeing early in the day allows the sun to dry and kill the plants
rapidly.
TRAPS:
Color
traps attract many flying insects. Cover
traps with Tanglefoot or heavy-grade oil or grease. Fermenting materials, such as beer or sugar
water and yeast, are well-known attractants to slugs. Set out saucers for them to drown in. Millipedes and sow bugs also fall for
this trap.
SOAPS: Insecticidal Soaps
are an excellent method of controlling common garden pests like aphids,
whitefly, mites and other soft-bodied insects.
Other
Resources about this subject:
Terra Viva,
Suppliers of biological predators
University Research:
UC
Davis IPM: Integrated Pest Management: An Overview for the
Consumer
UC
Davis IPM: IPM in Practice: Principles and Methods of Integrated
Pest Management
UC