Tomatoes: a primer
Davis Enterprise 05/26/05
What is it?
The tomato is a fruit
(a 'simple berry' in botanical parlance) which is used as a vegetable
in fact, it routinely tops surveys as America's favorite vegetable and is right
up there with roses as our favorite garden plant. Although the plant is subtropical,
and thus perennial in frost-free areas, it is grown as an annual in summer
gardens far to the north.
Where and how
to grow tomatoes?
Plant in full sun.
Amend the soil if you like, but go easy on the fertilizer or you'll get lots of
vine and less fruit. Water with your other vegetables until they're a couple of
feet high, then water about half as often and at least twice as long--a couple
of hours slow soaking is best. Stake or cage them to keep the plants contained
and the fruit off the ground. There are safe remedies for the few pest and
disease problems you might encounter: ask a garden professional to diagnose the
Flavor of tomatoes
is somewhat inherent to the variety, but is stronger if they are watered fairly
infrequently. The roots go quite deep, and allowing them to dry somewhat
between waterings (once established!) will concentrate the flavor in the fruit.
This means giving them a deep soaking every 7 - 10 days, and even less often is
fine as the season progresses.
are all those funny terms you read on tomato labels?
Some refer to the
growth habit, giving a hint as to the size of the plant:
Indeterminate means the vine keeps growing and flowering
all season. So it gets big! 8'+ is not uncommon, so they need to be staked or
caged to keep them from sprawling all over the ground. Yields are very high:
fruit continues to set as long as night temperatures are above about 55F, and
fruit will ripen until temperatures drop below about 50F. Most tomatoes are
indeterminate. Cherry tomatoes in particular are very large plants.
'semi-determinate' keep growing for a while after they start flowering.
Example: Celebrity. 'Dwarf
indeterminate' have very short internode distances, so the plants keep growing
and flowering all season but stay smaller overall. Examples: Better Bush, Husky
Red and Husky Gold.
Determinate means the vine mostly stops growing once
it has begun flowering. This makes for a more compact plant which will require
only a short stake or cage. Yields are lower, but certainly adequate.
Production tends to finish up in early fall. Ace is a well-known example. Some
are very small plants suitable for growing in pots: Patio, Roma.
Some of the terms
refer to disease resistance which has been bred into the varieties.
There are two soil
fungi that attack tomato roots, and both occur in this area. Older varieties
and heirloom types are not resistant. This can be a concern if you live in a
subdivision that was built on old row crop land, such as Mace Ranch, Aspen, or
Plants with a 'V'
on the label are resistant
to Verticillium Wilt. Plants with an 'F' on the label are resistant to Fusarium Wilt. A couple of
years ago, a new strain of Fusarium appeared in tomato growing regions,
including Yolo County, so some varieties carry an additional 'F2' designation
as being resistant to this disease. Tomato breeders try to stay one step ahead
of these new disease variants.
Tomatoes which can
tolerate root-knot nematodes have an 'N' designation. Keep in mind that the nematodes will continue to
live on the roots and survive from season to season, so it is still important
to plant them in a different location each year.
Note: contrary to
popular belief, simply planting marigolds with tomatoes will not deter
nematodes. A particular group called Signet marigolds will suppress or kill
root-knot nematodes when the bed is planted entirely in them--no tomatoes, no
other nematode host plants, just Signet marigolds--for an entire season. Nor
will marigolds repel or deter aphids or whiteflies, as is often stated by
proponents of companion planting. But they do look pretty in the garden, and
draw bees, butterflies and other beneficial insects.
So there's nothing wrong with planting them!
Some tomatoes are
resistant to Tobacco mosaic virus, a disease which can cause stunted and
unproductive plants. These will have a 'T' or 'TMV' designation on the label.
hybrid? Gourmet? Low Acid?
'Heirloom tomatoes are old varieties which
have been saved by dedicated growers. Often these are very productive in one
region (Nebraska Wedding, Arkansas Traveler), or have some unique
characteristic of color, shape, etc., so the seed has been saved from one
generation to the next. Yields are
generally lower, and most don't have built-in disease resistance, but they make
up for it in character, history, and pedigree.
going to save the seed of heirloom varieties, you do need to carefully exclude
the flower from being pollenized by a bee that has visited another variety after you've done the deed:
wrap the blossom with cheese cloth or a small paper bag to keep the bees away.
'Hybrid tomatoes won't 'come true' from seed
because they are F1 hybrids, carefully crossed from separate parents each time;
the seedlings will revert to the characteristics of one of the parents, or may otherwise
differ if the flower was pollenized by another variety in the garden.
which set fruit under cool conditions, or which ripen quickly, are used in the
northern or high elevation areas, though the yield is far less than in
California. Note: special cultural practices such as pruning off side shoots
('suckers') are done to hasten the production of ripe fruits in short-season
areas and are unnecessary here.
flowers don't need bees or any other special agents to pollinate them, although
bees will certainly visit the flowers. (Technical terms: a 'pollenizer' is
another plant which provides pollen. A 'pollinator' is the thing that does the
job: a bee, butterfly, person, etc. Easy word trick to remember the difference:
'pollenizers doesn't buzz'). Both male and female parts are present, and the
flower simply has to vibrate for them to come in contact, so movement of the
plant in the wind is sufficient. Greenhouse growers may need to tickle the
flowers. Weird exceptions: Currant tomatoes and their offspring have female
flower parts that stick out past the male parts, so they do need pollinators.
Don't worry, you'll get plenty of fruit anyway.
are neither better nor worse than hybrids! The varieties that have been saved
often have special flavor, are unusually large, or are striped, yellow, orange,
white, purple ('black'), or otherwise unique in appearance. Some do very well
in blind taste trials, but so do many hybrids. In fact, hybrid cherry tomatoes
routinely top taste tests.
''Gourmet' is a term usually applied to imported
types, mostly from Italy or France.
''Low acid' refers to varieties with mild, sweet
flavor. I've noticed a regional preference for these types from gardeners
relocated from the midwest and New England.
So what do you
How many? A couple of plants will provide you with a
summer's worth of fresh fruit. A half dozen will give you plenty to cook and
even freeze some. A dozen plants can provide enough for a year's worth of
canned or frozen tomatoes.
Which ones? With hundreds to choose from (my growers
have 120+ varieties between them), think about your site, space available, and
primary uses. Remember that production will vary from year to year, depending
on the weather. Try some new or old varieties each year -- you may find a new
'Limited for space: Ace, Gardener's Delight, Husky Gold, Husky
Red, Juliet, Patio, Roma.
'Limited sunlight: cherry tomatoes, especially Gardener's
Delight, Sungold, Sweet 100 (or newer versions); Yellow Pear, Red Currant are
unique and very, very productive.
'Reliable production, excellent quality fruit: Early Girl,
Celebrity are two I'm never without. Champion and Better Boy are also reliable heavy producers.
'Sauce or salsa: Roma and San Marzano are the classic pear
tomatoes; Principe Borghese is outstanding. Celebrity (productive,
thin skin), Mortgage Lifter
'Taste test winners: SunGold, a golden cherry type with super
rich, sweet flavor, tops taste tests everywhere. Early Girl, Super Sweet 100, Isis
Candy, Juliet are other winners. Costoluto Genovese is one of my favorites.
'Colorful fruit: Cherokee Purple, Caspian Pink, Lemon Boy, Marval
Striped. Yellow Stuffer has hollow fruit! Resembles a bell pepper, great for
'Varieties to avoid: Beefsteak types don't set fruit above 80 -
85 degrees, which is most of our summer here. Brandywine, a very popular
heirloom, isn't on my hit parade due to low yields.
Tomatoes are very
easy to grow in this area, with far higher yields and better flavor than in most
other parts of the country. Fruit or vegetable, sauce or salsa, and however you
say it -- toe-may-toe, toe-mahh-toe, tuh-may-ter -- mid-April to mid-June is a
great time to plant 'love apples' in your garden.
The fruit is
used as a vegetable. The Supreme Court ruled in the early 1900's that it was to
be considered a vegetable for tax purposes, as at that time imported vegetables
were taxed at a lower rate than imported fruits (most tomatoes were imported then). Confused? We eat lots of
weird plant parts as vegetables: the artichoke is a flower bud, kohlrabi is an
enlarged stem. So the term 'vegetable' really refers to how we eat something,
and the narrower term 'leafy vegetable' is used for things used as greens or
salads. Other fruits that are used as vegetables include summer squash such as
zucchini, and the tomato cousins peppers and eggplants.
See also our other articles:
Everyone loves tomatoes
Vegetables in Davis
Peppers and tomatoes: variety lists
© 2008 Don Shor, Redwood Barn Nursery, Inc., 1607 Fifth Street, Davis, Ca 95616
Feel free to copy and distribute this article with attribution to this author.
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