From: Gary W. Hickman, Horticulture Advisor
University
of California Cooperative Extension
August
15, 2001
ROTATING YOUR GARDEN
BACKYARD HORTICULTURE
By Gary W. Hickman,
Horticulture Advisor
University of California
Cooperative Extension, Mariposa County
Before parts of your summer
vegetable garden are replaced with winter plants, make a note of where each
crop is now planted. This will help
later if you have had trouble with some diseases this summer. By having such a garden map, you will be
able to rotate crops next season. A
particular vegetable should be grown in the same location only once every two
or three years. In fact, other
vegetables of the same plant family should not be planted in the same
place. For example, if you grow
cantaloupe this year, stay away from pumpkin, cucumber, and all the rest of the
melons for that spot in the garden next time.
Corn is an exception; it is in a plant group basically by itself, so any
vegetable can follow it. Peas and beans
are in the same family group. Tomatoes
are grown in many home gardens in Mariposa County. The tomato plant family also includes pepper, okra, potato, and
eggplant. The tuberous, or bulb, plants
are all relatives for rotating purposes, including beets, carrots, garlic, and
onion. The last major group of plants
are the leafy vegetables. This includes
cabbage, lettuce, radish, spinach, and turnip.
The reason behind rotation
of different groups of plants is that most of the plants in the same family
group have many common diseases. Many
of these diseases are difficult, or impossible, to control using
chemicals. The best solution for
control, then, is by crop rotation.
Another good way to plant
for a disease-free garden is to use resistant varieties. For our particular area, there are several
disease-resistant tomato varieties.
They all have VF or VFN in their names to indicate resistance to
verticillium, fusarium, and nematodes.
For many crops, however, there are yet no specific disease-resistant
varieties. For these, simply make sure
that the variety used is adapted to grow in our area. Lettuce, which can be planted now in warmer locations, comes in
many varieties. Remember not to plant
your winter lettuce where any leafy vegetables grew this summer. Another winter garden crop is carrots. Nantes, Imperator, Chantenay, and Amsterdam
are all good varieties.
Aside from crop rotation and selecting the best varieties, proper watering is the next most important factor in garden disease control. Deep, infrequent, furrow, or drip watering in the morning will greatly reduce bacterial and fungal problems. This will keep the soil moist down in the root zone without saturating. It will also keep the leaves dry, which results in fewer foliage disease problems.
Sometimes,
despite all your best efforts, you can still get diseases in your home
garden. In some cases, chemicals will
help prevent the spread of the infection.
Curing an already infected plant is usually not possible. If this happens, the best control is to remove
the diseased plant and destroy it. Then
remember to rotate your crops next season.
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