"Make hay while the sun still shines"
is an adage that certainly pertains to spring gardening activities
in this area of Texas.
Gardeners should take advantage of any current
dry conditions to prepare planting sites. Rental stores do
not have a tremendous demand for roto-tillers in early spring,
so smart gardeners can beat the rush by acting now. This unpredictable
Texas weather could also take a “wet” turn and
make soil preparation at a later time unfeasible. This would
be disastrous since crops such as beets, broccoli, cabbage,
carrots, collards, corn, kohlrabi, lettuce, mustard, onions,
parsley, sugar snap peas, potatoes, radish, spinach and turnips
should be planted no later than February.
The first step in creating a productive garden
is site evaluation. All vegetables are most productive in
full sunlight conditions. If your garden site does not receive
at least 8 hours of direct sunlight daily, you will not successfully
produce those crops which have seed?bearing fruit. These include
tomatoes, peppers and eggplant. By "successfully produce",
I mean tomato plants which will yield at least 15 to 20 pounds
of fruit per plant. Greens (lettuce, collards, mustard) and
root crops (carrots, beets, radish) can tolerate shady conditions,
but will not excel.
Another important factor of successful gardening
is sufficient fertilization. However, you must use care not
to use excessive amounts of fertilizer.
Through the years, I have advocated the use
of ammonium sulfate (21?0?0) as a recommended nitrogen?only
fertilizer for older gardens where complete-analysis fertilizers
have been used year after year. Because of the abundance of
potassium in the native soil of our area, and because of the
build?up of phosphorus which occurs after several seasons
of fertilizing with a complete fertilizer, a high nitrogen
fertilizer can be recommended as the best selection for most
To continuously use a balanced fertilizer in
gardens promotes the occurrence of nutrient deficiencies of
such minor elements as iron and zinc. However, ammonium sulfate
(21-0-0) will release IMMEDIATELY release, and the majority
of folks can and WILL burn their plants by adding too much!
The recommended application is one pound per 100 square feet.
Since one pound per hundred isn’t enough to show up
white (with fertilizer) on the ground, most folks will add
I now recommend that a complete fertilizer with
percentages of nitrogen, phosphorus, and potassium should
be used in new gardens that are less than 2 years old. This
includes the use of a 50% slow release fertilizer (our most
common is 19?5?9 but anything close to a 3?1?2 ratio is OK???this
is not a precise operation) during bed preparation for gardens
or flowers at the rate of 3 pounds (3 cups full) per 100 square
feet. For flowers and vegetables, I recommend one pound (one
cup) per 100 square feet of the same slow release formulation
every 3 weeks beginning after fruit-set or full bloom, and
every 2 weeks for foliage crops. If un-decomposed organic
material (including all materials sold as “compost”)
is worked into the soil, these rates should be DOUBLED for
the first 3 months to prevent nitrogen tie-up by micro-organisms
trying to decompose the organic materials. Animal manures
may be substituted for commercial fertilizer and used at a
rate of 60 to 80 pounds per 100 square feet of garden area.
The most common problem during early spring,
when plants are growing vigorously, is iron chlorosis-- or
lack of iron. This irregularity is characterized by streaks
of green through a predominately yellow leaf. In severe cases,
brown margins or spots will develop, but this will occur after
the leaf has been yellow for a period of time.
Plants which are extremely susceptible to iron
chlorosis include okra, black-eyed peas, beans, azaleas, gardenias,
peaches and pears. This lack of iron in a plant is not necessarily
caused by insufficient iron in the soil. Because of the alkaline
soil conditions of this area, iron can be present in the soil,
but not available for plant uptake because of encapsulation
by calcium or a strong adhesion to another soil mineral. So
what can we do to make yellow plants green?
First of all, don't aggravate the condition
with continuous applications of balanced fertilizers. Secondly,
make sure that your plants have access to an available, note
I say available, iron source. Iron sulfate sold as copperas
can be used, as well as any product which has at least 16%
iron as a component of the mix-- such as Ironnate or Iron
Plus (16% iron plus nitrogen), or glauconite (Greensand with
18% iron -- use 10 pounds per 100 square feet). Iron sulfate
can be applied as a foliar spray but be sure to use one teaspoon
of liquid detergent per gallon of spray to insure uniform
For gardens, soil applications are recommended.
One effective technique of application is to mix iron sulfate
with organic material (leaves, grass clippings, etc.). Simply
add 7 pounds of iron sulfate (copperas) to 400 pounds of organic
matter (or one cup to a bushel of organic material). You can
add more without danger of plant damage. As the organic matter
decomposes, the iron that has "stained" the surfaces
will be slowly released for plants to use. Such "fortified"
organic material can be worked into the soil prior to planting
and/or used as a mulching material for newly established seedlings
and transplants. Another technique in avoiding iron chlorosis
problems will be discussed later. It will be added after raised
beds have been prepared.
Certain other ingredients should also be added
to boost yields. The latest research indicates that the presence
of available calcium prevents certain physiological disorders
of vegetables as well as increases the efficiency of nitrogen
uptake and stimulates growth. In the highly calcareous soil
of Texas, it is difficult to imagine that plants need more
calcium. However, research indicates that much of the calcium
in the soil is not soluble or available for plant use. The
best remedy for this situation is the addition of gypsum.
Gypsum (calcium sulfate) is a neutral product that will not
cause our soils to become more alkaline. We sure don't want
that! Gypsum is sold as Sof?N?Soil or gypsum, and is recommended
at the rate of 40 pounds per 100 square feet.
An additional step can be taken after beds
have been prepared to avoid chlorosis problems later, as well
as installing a cheap "starter solution" for seedlings
and transplants. After planting beds have been firmed, make
a 3-inch deep furrow for seed, or a 6-inch deep furrow for
transplants. The furrow should be made down the center. Into
this furrow, distribute evenly 1/2 pound (1/2 cup) of iron
sulfate (copperas) and 1/2 pound (1/2 cup) of super phosphate
(0?20?0) per 10 linear feet of bed. This band of iron and
phosphorus will provide a concentrated source of available
iron and available phosphorus for use as a "starter"
solution on young and growing plants. Cover the band of iron
and phosphorus with at least 2 inches of soil.