020)

is the soil being maintained in a way which will enable it to
retain moisture and nutriments

are the plants receiving enough sun
are the plants being grown in season,

Another method of providing for plant health and for mini-.
mizing insect and disease problems is to keep a correct balance
of phosphorous and potash in the soil in relation tothe amount
of nitrogen present. (See page 26.) The optimal ratio among
these elements is still to be determined. Research also needs to
be completed to determine the minimum amounts of these
elements (in pounds per 100 square feet) which should be in the
soil. (Smaller amounts of organic fertilizer elements are re-
quired, since they break down mcre slowly and remain available
to the plants for a longer period of time.)

Proper planning of the garden can eliminate many insect
and disease problems!

Q Use seeds which grow well in your Climate and soil.

QO Use plant varieties which are hardy, insect resistant, and
disease resistant. New strains, especially hybrids (whether
developed for higher yields, disease resistance or other rea-
sons) should usually be avoided. Hybrids often produce food
of lower nutritive value in comparison with older strains
and often use up nutriment from the soil at a more rapid rate
than the rate at which a living soil can produce nutriment.
Hybrids are also often very susceptible to a few diseases
even when they are greatly resistant to1.iuny prevalent ones.

Companion plant: grow vegetables and flowers together that
grow well with each other.

Normally, do net put the same vegetable in the same growing
bed each year. This practice invites disease.

Rotate your crops: follow heavy feeders with heavy givers
and then light feeders.

Encourage natural insect control by enlisting the aid of nature:

Birds—some are vegetarians. Others are omnivorous. A bird
which stops for a seed snack may remain for an insect dinner. A
house wren feeds 500 spiders and caterpillars to her young in
one afternoon, a brown thrasher consumes 6,000 insects a day,
a chickadee eats 138,000 canker worm eggsin25daysanda .
pair of flickers eat 5,000 ants as a snack. A baltimore oriole can
comsume 17 hairy caterpillars a minute. The presence of birds
may be encouraged by the use of moving water, the planting of

63, Beatrice Trum Hunter, Gardening Without Potsons, Berkeley Publishing Corp., New
York, 1971, pp. 31, 37,42, 43, 48. The Berkeley Edition was published by arrangement with
the Houghton Mifflin Company, who are the orginal publishers of Gardening Without Potsons.

’
.

98. A Balanced Backyard Ecosystem and Insect Life