Tomatoes or Tomates
A major consideration when attempting to produce maximum tomato yields is
variety selection. Tomatoes listed on the recommended vegetable variety
table include Celebrity, Merced, Bingo, Whirlaway and Surefire(medium-size
fruit) for large fruited types and Small Fry for the cherry type. Such recommendations
are based on at least 3 years of field tests including spring and fall conditions.
Even though all of these varieties are reliable producers never plant
only one variety. By using several varieties, gardeners increase their chance
of success regardless of environmental conditions which may occur. Merced
is the highest quality producing variety provided it is furnished
with optimum growing conditions. Optimum growing conditions include full
sunlight and high levels of manure fertilization and/or regular side dress
applications of ammonium sulfate. This is necessary for adequate foliage
production which protects tomatoes from sunscald in the spring. If such
an effort doesn't seem worthwhile, use low maintenance varieties such as
Celebrity.
One of the most important techniques for successfully growing a bumper crop
of tomatoes is to use a starter solution at transplanting time to insure
adequate fertility during early growth of the plants. Purchase starter solutions
at local garden centers or make them at home by mixing 2 level tablespoons
of super phosphate in a gallon of water. Commercial starter solutions are
generally preferable to home mixes because they are usually higher in phosphates
and are completely water soluble. After following label directions for mixing
the starter solution, pour about a cup or so in each transplant hole.
Set the transplant directly in the center of the hole and fill with soil.
If the transplant is leggy and tall, lay the stem portion of the plant on
its side rather than digging a hole deeper to accommodate the taller plant.
Setting tomato transplants too deep, especially in heavy clay soils, often
slows early growth, resulting in later maturity and fewer tomatoes. If your
soil is sandy, deep planting generally does not cause a problem.
When planting, make certain the peat container is completely beneath the
soil level. If it is exposed to the air, it acts like a wick and rapidly
dries out the root ball, often stunting or perhaps killing the plant. When
firming the plant in, leave a slight depression around it to hold additional
water from spot watering or rainfall.
Either stake-and-tie or cage all tomatoes. Staking-and-tieing produces larger
tomatoes earlier but less overall fruit than caging. When staking tomatoes,
put the stake in shortly after transplanting to lessen root damage. A 6-foot
stake set 10 inches deep in the soil works well. As the plant grows taller,
tie it loosely to the stake every 12 inches with pieces of rag, twine or
soft material.
A proven method of growing tomatoes involves using cages to support the
plant rather than staking and pruning. Cages are nothing more than cylinders
made of reinforcing wire, hog wire or similar material to support the plant
and keep the fruit off the ground. Make the cylinder 18 to 20 inches in
diameter and 2 to 5 feet tall. Concrete reinforcing wire is generally considered
best and is available in rolls of varying lengths, most commonly in 5-foot
widths. It takes a 5-foot length to make a tomato cage 18 inches in diameter.
Cages are held together by bending and crimping the ends of the wire around
one of the vertical wires.
Place the cages over the tomato plants shortly after planting. One plant
inside each cage is recommended. For support, snip off the bottom ring of
the cage and push the cage into the ground. It is highly advisable to support
the cage with wooden or metal stakes to keep the cage from falling over
later in the season.
Several conditions cause tomatoes to fail to set fruit. Improper fertilization,
high nighttime temperatures (above 70°F.), low temperatures (below
50°F.), irregular watering, insects such as thrips and planting the
wrong variety may result in poor fruit set. Any one of these can cause poor
fruit set, but combinations are even more damaging.
Few, if any, large-fruited tomato varieties will set fruit during cool,
cloudy weather. Even some of the so-called "heat setting" types
drop blooms in cloudy weather conditions. These tomato blooms leave such
a distinct stem when they fall from the bloom cluster that many gardeners
think the blooms have been eaten off by insects. Blossom-set hormones, sold
as Blossom-Set, are helpful in setting or holding some of these blooms by
"fooling" the bloom into believing it has been pollinated. Most
of this poor fruit set caused by cloudy weather conditions directly relates
to improper pollination of the blooms. Tomato flowers are wind or mechanically
pollinated, so gardeners don't have to have bees.
Most insects are detected and controlled using a recommended insecticide.
Worms or caterpillars are the most conspicuous to gardeners. Worms (caterpillars)
come in a variety of colors and shapes, but all damage plants by eating
holes in leaves. They feed on tomatoes as well as most garden vegetables.
Entire plants may be eaten by these caterpillars if they occur in large
numbers. These can be easily controlled by using Dipel, Thuricide, Bio-Spray
or Biological Worm Killer. These materials contain the bacteria Bacillus
thuringiensis that kills only caterpillars and does not harm beneficial
insects. Good coverage of upper and lower leaf surfaces is necessary for
best control.
Spider mites are the least detectable pest. Spider mites are tiny spider
like, plant chiggers that feed on the undersides of leaves of many garden
vegetables and flowers. Most mites are about 1/32 inch long and live and
feed in a web they produce on the leaves. They reproduce rapidly and can
damage plants in a short time. Inspect plants frequently by examining the
underside of leaves with a magnifying glass. When large populations of mites
are present, leaves appear "stippled" or dotted with yellow, and
webbing is usually present on the underside of leaves. Spray plants with
Kelthane with 1 teaspoon of liquid soap added to the mixture. Repeat the
spray every 4 days for four consecutive applications. Sulfur also controls
mites but do not apply on squash and other vine crops.
Control other insects by using insecticides such as diazinon, malathion,
Sevin or endosulfan which can be legally used on the appropriate crop. Avoid
the blanket use of any specific insecticide. Otherwise, insects may become
resistant to the insecticide. It is a good idea to switch insecticides periodically.
Insects can be harmful, but disease can be disastrous. Diseases must be
prevented, not cured.
There are two main diseases which cause this disaster every spring. Early
blight (Alternaria) and Septoria leaf spot are the culprits. Early
blight is characterized by irregular, brown spots that first appear on older
foliage. With age, the spots show concentric rings forming a target pattern.
A yellow, diffuse zone is formed around each spot. Although this fungus
disease can be observed throughout the year, it is most common during the
fruiting period. The more tomatoes a plant produces, the more susceptible
to and disastrous are the effects of an early blight infection. The fungus
is favored by high humidity and high temperatures. The only control is prevention
which begins when the plant is transplanted. During periods of high humidity,
which includes most of the spring, apply a fungicide weekly. The best fungicide
to use is one containing chlorothalonil (Ortho Vegetable Disease Control
or Fertilome Broad Spectrum Fungicide).
Another destructive foliage disease of tomatoes is Septoria leaf spot. It
may attack tomatoes at any time; however, it generally causes problems after
the fruit begins maturing. In checking plants for this disease, look at
the older foliage. The fungus is characterized by circular lesions with
gray centers surrounded by dark margins. With age, the spots become covered
with tiny black specks from which spores grow. Lesions are smaller and more
numerous than the early blight organism. The fruit is rarely affected, but
stems and blossoms are attacked. The disease overwinters on old tomato vines
and wild relatives of the tomato family. The fungus is most active when
temperatures are between 60° and 80° F. and during periods of
high humidity. Apply a fungicide containing benomyl. Because benomyl is
a systemic fungicide which goes into the plant, it lasts longer and does
not have to be applied as often. To provide complete fungus protection from
Septoria and early blight during spring periods of high humidity, mix benomyl
with the weekly chlorothalonil every other week.