If you purchase transplants, look for sturdy, short, dark green plants.
Avoid plants that are tall, leggy, or yellowish, or have started
flowering. Transplants that are too mature often stall after
transplanting while younger, smaller plants pass them by, producing
earlier and more fruit.Starting
your own plants from seed gives you more choices of which variety to
grow. But if you start your own plants, be sure you have a place where
they can get enough light. Even a sunny, south-facing window is barely
adequate. Consider using a grow light to supplement sunlight.
Don’t
start plants too early. Sow seeds indoors 6 to 8 weeks before
transplanting outside. Plant them 1/8 inch deep in sterile seed
starting mix in flats or cells. Seeds germinate best at 75 F to 90 F.
Then grow transplants at about 70 F.
Don’t rush to transplant,
either. Cold soil and air temperatures can stress plants. Wait at least
a week or two after the last frost. Nighttime temperatures should be
consistently above 45 F. Use black plastic mulch to warm soil and/or
row covers, hot caps or other protection to keep plants warm early in
the season. Remove covers whenever temperatures exceed 85 F.
Harden
off plants before transplanting by reducing water and fertilizer, not
by exposing to cold temperatures, which can stress them and stunt
growth. Transplants exposed to cold temperatures (60 F to 65 F day and
50 F to 60 F night) are more prone to catfacing.
Space transplants:
- 12 to 24 inches apart for determinate varieties
- 14 to 20 inches apart for staked indeterminate varieties
- 24 to 36 inches apart for unstaked indeterminate varieties
Unlike
most plants, tomatoes do better if planted deeper than they were grown
in containers. Set them in the ground so that the soil level is just
below the lowest leaves. Roots will form along the buried stem,
establishing a stronger root system.
To reduce root disease risk,
don't plant on soils that have recently grown tomatoes, potatoes,
peppers or eggplant for at least two years.
Mulch plants after
the soil has warmed up to maintain soil moisture and suppress weeds.
Tomatoes need a consistent supply of moisture. If it rains less than 1
inch per week, water to make up the difference.
Many factors (in
addition to your choice of variety) affect total yield, first harvest
and fruit quality. Raised beds, black plastic mulch and providing
consistent moisture by watering or through drip irrigation are good
ways to improve all three.
How you provide support to plants can
also affect performance. Determinate varieties do not need staking. But
staking and pruning indeterminate varieties can hasten first harvest by
a week or more, improve fruit quality, keep fruit cleaner, and make
harvest easier. Staking and pruning usually reduces total yield, but
fruits will tend to be larger. Staked and pruned plants are also more
susceptible to blossom end rot and sunscald. Allowing indeterminate
varieties to sprawl reduces labor, but takes up more space and plants
are more prone to disease.
Wooden tomato stakes are typically
about 6 feet long and 1 � inch square, but you can use similar
materials. Drive stakes at least 8 to 10 inches deep at or soon after
transplanting so as not to damage roots.
Prune tomatoes to one or
two vigorous stems by snapping off “suckers” (stems growing from where
leaf stems meet the main stem) when they are 2 to 4 inches long. Tie
stems to stake with soft string, twine or cloth, forming a figure-8
with the stem in one loop and the stake in the other. This gives the
stem room to expand without being constricted. Start about 8 to 12
inches above the ground and continue to tie at similar intervals as the
plant grows. As an alternative to using individual stakes, grow several
plants in a row between heavy-duty stakes or posts spaced about 4 feet
apart, and use twine to weave in and out around posts and plants.
Growing
tomatoes in cages is a good compromise between labor-intensive staking
and just letting them sprawl. You can purchase tomato cages at your
local garden center, or simply bend a 6-foot-long piece of 4- to 6-inch
wire mesh into a cylinder about 22 inches in diameter. (Cattle fencing
or concrete reinforcing wire mesh work well for this.) Place cage
around plants soon after transplanting and anchor with stakes.
Avoid
excessive N applications, which can cause excessive foliage and poor
fruit set. Also avoid using fresh manure or high nitrogen fertilizers
(those with three or more times nitrogen than phosphorus or potassium).
Poor fruit set can also be caused by heavy rainfall or temperatures
that are either too high (above 90 F) or too low (below 55 F).
On
most soils, you can sidedress about 1/2 cup of 5-10-5 per plant and
work shallowly into the top inch of soil when fruits are about 1 inch
in diameter and again when harvest begins.
To avoid other common tomato problems:
- Keep
soil evenly moist to prevent blossom end rot. This can also help
prevent cracking when fruit absorbs water too fast after heavy rain
following dry conditions.
- Do not remove leaves that shade fruit to prevent sunscald.
- Catfacing
(misshapen, deformed fruit) is caused by incomplete pollination,
usually due to cold weather. Don’t rush to transplant until weather has
stabilized and soil is warm.
Tomato hornworms - Hand pick larvae. This pest is frequently controlled by natural enemies.Aphids
- A hard stream of water can be used to remove aphids from plants. Wash
off with water occasionally as needed early in the day. Check for
evidence of natural enemies such as gray-brown or bloated parasitized
aphids and the presence of alligator-like larvae of lady beetles and
lacewings.
Whiteflies - Do not purchase whitefly-infested transplants. Inspect carefully before purchasing.
Colorado potato beetle - Handpick and destroy beetles, eggs and larvae.
Cutworms - Control weeds. Cardboard collars around each plant give good protection.
Flea
beetles - Use row covers to help protect plants from early damage. Use
in place at planting and remove before temperatures get too hot.
Control weeds.
Blossom end rot - Water during drought or mulch to keep moisture level
constant. Grow on soil high in organic matter. Fertilize properly.
Avoid cultivating close to plants.Catface - Grow locally recommended varieties and provide adequate fertilizer and water for vigorous growth.
Early
blight, Septoria leaf spot - Locate new plants in a part of the garden
different from previous year's location. Avoid wetting foliage if
possible. Water early in the day so aboveground plant parts will dry as
quickly as possible. Avoid crowding plants. Space apart to allow air
circulation. Eliminate weeds around plants and garden area to improve
air circulation. Practice plant sanitation. When plants are not wet,
carefully remove and destroy affected plant parts. In autumn, rake and
dispose of all diseased leaves and stalks. Septoria occurs early in the
season, preferring cool, wet weather. Use clean transplants and remove
lower infected leaves.
Late blight - Use same cultural control
strategies as above. The fungus that causes late blight has recently
become a major threat to home gardens and commercial growers because of
migration of new more aggressive strains (genotypes) into the United
States. Verification of late blight diagnosis and
implementation of prompt control measures are hightly recommended.
Cultural controls mentioned above may not adequately control these new
strains.
Fusarium wilt - Use same cultural control strategies
as above. Plant resistant varieties such as Pik-Red, Better Boy, Duke,
Freedom, Supersonic, Jet Star, Springset and Floramerica.
Verticillium
wilt - Use same cultural control strategies as above. Plant resistant
varieties such as Supersonic, Jackpot, Basketvee, Sunny, Jet Star and
Springset.
