| Q: Every year,
I seem to have lots of green tomatoes on my plants when the
first frost comes. What can I do with these unripe fruit? |
| A: Often, the first killing frost of the season may be
followed by weeks of mild weather. First, try protecting
the plants from frost. When a frost is forecast, cover
the plants. Try using an old sheet, a plastic tarp, or
even a floating row cover material like reemay. Place it
over the plants in the late afternoon and take it off the
next morning after temperatures have risen above freezing.
This will also be a good time to root prune the
plants. Root pruning means taking a spade and pressing
it into the soil about 6-8 inches. Do this in a circle,
one foot from the base of the plant. By doing this you
will sever parts of the root which will usually hasten
ripening.
When frosts are becomoing more regular, it's time to
cut the plants at the base and take them to a cool location,
like a basement or garage. Hang the plants from the rafters
and you will see the fruit slowly ripen. The fruit will
not be as tasty as those in the summer, but they will be
better than what you will find in the supermarket.
Instead of removing the whole plant, harvest all tomatoes
of good size and place them in paper bags in a cool location.
Tomatoes do not need light to ripen and should never be
placed on a windowsill! Place the tomatoes in a single
layer in the bags. Tomatoes stacked on top of each other
are more likely to be damaged. When placing the fruit in
the bags, try to separate them based on ripeness (i.e.,
put all fruit of a similar ripeness in the same bag). Check
the bags regularly and remove fruit as it ripens.
|
| Q: What causes a big black spot on the blossom-end of
my fruit? |
A: The problem is called Blossom-End Rot (BER) and is
caused by a lack of calcium within the fruit. When calcium
reaches low levels in the tomato, the fruit simply dies back
at the bottom leaving the characteristic black or brown spot.
Calcium is present in most soils in adequate amounts. The
problem is that the plant cannot absorb enough calcium through
its roots because of dry soil conditions. That's because
calcium is taken up by the roots along with water. If, for
some reason, water uptake is restricted, calcium uptake will
stop.
What can you do about it? Have your soil tested to make
sure you have enough calcium in the soil. If you don't, add
either limestone (if the soil's acidity level or pH is below
6.0) or gypsum. If calcium levels are adequate, the most
important control measure is to maintain optimum soil moisture.
Whenever tomato plants are allowed to experience the slightest
bit of water stress, you are causing BER. To maintain good
soil moisture, try using a mulch of straw, leaves, or even
grass clippings to prevent evaporation.
Tomatoes need about one inch of water per week as a minimum.
If you do not get this through rainfall, you will need to
apply the water As a rough estimate, each tomato plant needs
approximately 3-5 gallons of water each week. If you use
a mulch, this amount may be cut in half. When watering, don't
lightly sprinkle the ground. Apply the water so it enters
the ground and moves through the soil to a depth of 8-12
inches. Shallow watering only encourages shallow rooting
which leaves tomato plants more prone to wilting.
|
| Q: My tomato plants look great in the morning and then
they wilt in the afternoon. I have a lot of green fruit that
need to ripen...will these plants live to produce ripe fruit? |
A: There are two pathogenic fungi that can cause
wilts in plants: Fusarium and Verticillium. When you purchase
seed or tomato plants, look at the variety name and the letters
that follow. Most varieties are VFN resistant, which means
they are resistant to Verticillium, Fusarium, and nematodes.
Use varieties that are VFN resistant.
The other possible cause for late afternoon wilting is
known as walnut wilt. The roots of walnut trees secrete a
chemical that is very toxic to tomato plants and will cause
them to wilt when they are stressed in the heat of the day.
Planting tomatoes in locations where there are no walnut
trees is the only answer.
|
| Q: In May and June, dark brown to black leaf spots developed
on the leaves of my tomato plants. Some were as large as
an inch in diameter. What caused these spots? |
A: Leaf spots can be caused by fungi that are parasites
on your tomato plants. The two most common diseases are early
blight and Septoria leaf spot. Spots caused by early blight
can get as large as an inch in diameter and will have a bullseye
appearance. Septoria leaf spots are dark at first and then
become more gray in the center as they age. Both of these disease
will cause the leaves of the plant to fall off prematurely.
These fungi are mostly a problem during prolonged periods of
wet weather.
|
| Q: My tomato fruit looked beautiful but after I harvested
them, several developed sunken circular areas that eventually
rotted. What caused this to happen? |
A: Sunken circular areas on tomato fruit are typical
symptoms of a disease known as anthracnose, which is caused
by a fungus. Although this fungus may attack both green and
red fruit, symptoms do not develop until the fruit ripen. A
perfectly good looking tomato will often develop these sunken
areas during storage. This disease is typically a problem on
tomato fruit that are sitting on the ground and when there
have been prolonged periods of wet weather.
|
| Q: How do I control diseases in the future
on my tomatoes? |
A:
- The first control measure is to purchase
or produce disease-free transplants. Don't purchase tomato
plants that have spots on them or that are yellowing
or wilting.
- Consider the location in your garden: it is best
not to plant tomatoes in the same area in consecutive
years.
- Research has shown that placing straw, plastic,
or paper mulches around the base of the tomato plants
will help reduce development of disease. Mulching will
provide a physical barrier between your tomato fruit and
any disease organisms that may be lurking in the ground.
- If disease is present on your tomato plants, spread
of the disease can be reduced by using fungicides that
are available from home garden stores.
|
| Q: Should tomato plants be suckered at the first sight
of blooms? If so, why and how is this done? |
| A: Pruning is the selective removal of "suckers",
those sideshoots that grow from the crotch above a leaf branch.
If these are not removed, each sucker will become a main stem
with flowers, fruit and even more suckers. By pruning tomatoes,
you are reducing some of the potential fruit the plant could
produce. Rather than a plant producing 80 fruit, a pruned plant
may produce only 40. Since there are fewer fruit each will
weigh more. This doesn't mean that a cherry sized fruit will
turn into a giant beefsteak type but it will typically add
an ounce or two, depending on the level of pruning.
Tomatoes have three different growth habits: determinate,
indeterminate, and semi-determinate. Determinate types are
relatively small, often referred to as bushy or compact.
Each short branch ends in a flower cluster and the plant
does most of its growing before any fruit are set. The tomatoes
tend to ripen at once, usually over a short 2 to 3 week period.
After most of the tomatoes are harvested the plant yellows
and additional production is limited. If grown upright, the
plants are seldom more than 2 - 3 feet tall. Some examples
of this type include Pik-Red, Early Girl, and Super Bush.
In general, many of the earliest varieties are determinate
types.
Contrast that growth habit to indeterminate types. These
are the traditional, large home garden varieties. They produce
plants as large as you will allow them to grow. They have
many widely spaced branches, numerous suckers, and produce
tomatoes all season long. These are the varieties that can
be manipulated in all sorts of fashion to make the plants
conform to your needs. Examples of this type of growth habit
include Big Beef (most of the beefsteak types), Supersonic,
and Big Boy. In between these two are the semi-determinate
types. They will produce suckers like indeterminate types
but not as many and the plant will grow between 3 and 5 feet.
Examples of semi-determinate types include Celebrity and
Mountain Pride.
Knowing the growth habit of the variety you are growing
is critical in determining whether a plant can be pruned
and the level of pruning. Indeterminate varieties will have
many suckers and branches, each producing many flowers and
eventually fruit. These can be pruned and pruned severely.
Determinate types, however, are pruned slightly if at all.
Any pruning done on a determinate removes a finite number
of blossoms and fruit. If you prune all the suckers on a
determinate type you will have a small plant, few fruit and
lots of sunscald due to a lack of foliage and shading. You
will also dramatically reduce your yield. Semi-determinate
types can be pruned but not nearly as much as indeterminates.
What's a gardener to do? Remember, you can grow perfectly
fine fruit without pruning your plants. But if you want to
prune, here are a few guidelines. For determinate types,
there is no need to prune at all. For indeterminate types,
allow one, two, or three suckers to grow from the base of
the plant. Each of these will become a main stem with lots
of flowers and fruit. Prune off all the others suckers and
provide the plants with strong support. Research has shown
that the best time to remove suckers is when they are about
3 to 4 inches long. For the semi-determinate types, limit
your pruning. When the plant is 8 - 10 inches high, look
carefully and observe the first flower cluster on the stem.
Remove all the suckers below the flower cluster except for
the one immediately below the cluster. You may have to go
back and give these a second pruning 7 to 10 days later.
Remove no more than that or you run the risk of pruning too
much. The amount of pruning among these varieties to produce
optimum yields varies. Some varieties would do better if
you left 2 suckers below the flower cluster. Experiment and
see which works best for the variety you are growing. Hope
this is helpful. Any questions, please let me know.
|
Q: I see in my parks Catalog that they classify their
tomatoes as "Indeterminate and Determinate". What
does this refer to.
i.e..hybrid non hybrid?
Does it make any difference to where I plant my tomatoes? |
A: Tomatoes have three different growth habits: determinate,
indeterminate, and semi-determinate. Determinate types are
relatively small, often referred to as bushy or compact.
Each short branch ends in a flower cluster and the plant
does most of its growing before any fruit are set. The tomatoes
tend to ripen at once, usually over a short 2 to 3 week period.
After most of the tomatoes are harvested the plant yellows
and additional production is limited. If grown upright, the
plants are seldom more than 2 - 3 feet tall. Some examples
of this type include Pik-Red, Early Girl, and Super Bush.
In general, many of the earliest varieties are determinate
types.
Contrast that growth habit to indeterminate types.
These are the traditional, large home garden varieties.
They produce plants as large as you will allow them to grow.
They have many widely spaced branches, numerous suckers,
and produce tomatoes all season long. These are the varieties
that can be manipulated in all sorts of fashion to make the
plants conform to your needs. Examples of this type of growth
habit include Big Beef (most of the beefsteak types), Supersonic,
and Big Boy. In between these two are the semi-determinate
types. They will produce suckers like indeterminate types
but not as many and the plant will grow between 3 and 5 feet.
Examples of semi-determinate types include Celebrity and
Mountain Pride.
At one time, all tomato plants were indeterminate types. In the early part
of the 20th century, a compact, determinate plant was field growing in a
field of tomatoes - a natural mutation. From that one plant has come all
the determinate plants,
So it has nothing to do with hybrid or open pollinated.
There are probably more non-hybrid, open pollinated indeterminate
types than determinate types but you can find hybrids in
both vine types. As far as where you should plant, they both
have the same requirements but the indeterminates will take
up more room.
Hope this helps! |
| |
| For more gardening resources
visit: |
| Diagnosing
Vegetable Problems |
| Cornell Gardening
Resources Web Site |
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