October is the month of stinking delights and except for the
onion, garlic, Allium sativum L., is probably the most widely
used "stinker" of the cultivated Alliums. Garlic is
a condiment often used as a flavoring and seasoning in prepared
food products such as soups, sausages, and pickles. It is also
frequently used in salads and other home cooking. Garlic salt
is made from pulverized, dehydrated garlic cloves. In some countries,
the green tops are used as well as the bulbs.
The medicinal value of garlic has been noted throughout history.
Its use has been associated with treatments for polio, tuberculosis,
typhus, and cholera. Scientists at Case Western Reserve University
have now found that allicin, a bactericide in garlic, can inhibit
the growth of enzymes in tumor cells. Mice inoculated with cancerous
cells and given allicin did not develop malignant tumors.
The Romans disliked the strong flavor and odor of garlic,
but fed it to their laborers to make them strong and to their
soldiers to make them courageous.
Garlic does not produce true seed but is propagated by planting
cloves, which are the small bulblets, or segments, making up
the whole garlic bulb. In Texas, garlic is a perennial plant.
Garlic can be planted in the late fall. It is extremely frost
hardy, and if planted in October, may have tops showing above
the soil and be well rooted by November. The crop will mature
in June. The growing period before bulbing may be too short
for satisfactory yields if planted in the spring.
Bulb formation in garlic occurs in response to the lengthening
days of spring, and bulbing and maturity are considerably hastened
if temperatures are high. In addition to these requirements,
the dormant cloves (divisions of the large bulb), or young growing
plants, must be exposed to cold temperatures between 32 and
50 degrees F. for one or two months in order to initiate bulbing.
Plants that are never exposed to temperatures below 65 degrees
F. may fail to form bulbs. With fall plantings, the cold treatment
is accomplished quite naturally throughout winter. However,
excessive exposure to low temperatures may initiate cloves in
the axils of the leaves near the bulb surface, which causes
the maturing bulbs to appear rough. Roughness may also be increased
by early planting, heavy fertilization, wide spacing and other
factors that favor vigorous growth of individual plants.
Seedstalk formation (bolting) is not induced by exposure to
low temperatures, as is the case with onions. This means that
a wide range of fall planting dates is permissible for this
The cloves, when used for propagation, are commonly termed
'seed' or 'sets.' Most seed companies sell garlic cloves under
the name of garlic sets, and make no mention of separate varieties.
In Texas, seed firms may sell two distinct types of garlic varieties:
a.) Creole (Early Louisiana, White Mexican), and b.) Italian
(Late or Pink). Creole is earlier than Italian, but does not
store as well.
Bulbs that have been selected for planting are usually stored
in unheated areas with the dry tops attached. The separation
of bulbs into cloves for planting should be delayed until planting
time, as whole bulbs store better than prepared cloves. To prepare
the cloves, the tops of the bulbs are cut or torn off and the
bulbs are broken apart, usually by hand. The mother bulbs should
be thoroughly dry before breaking.
Each large garlic bulb contains about 10 cloves. All the cloves
are planted except the long, slender ones in the center of the
bulb and those that are less than one gram in weight. Also,
bulbs that have side growths should be discarded. Garlic yields
generally increase as the mother bulbs increase in size from
small to large. This appears to be an effect of clove size,
since large mother bulbs usually yield larger cloves.
Garlic is usually planted 3 to 6 inches apart in rows 18 to
24 inches apart. Higher yields can be obtained with cloves planted
as close as 2 inches and in rows that are 12 inches apart. But,
as the density of the planting increases, the size of the individual
bulb decreases. The depth of planting is 1 to 2 inches, depending
on soil conditions. The cloves must not be so deep that the
soil will interfere with the swelling of the bulbs, nor so shallow
that rain will wash them out. The vertical placement of cloves
by hand into planting furrows will insure production of straight?necked,
Soil that is suitable for onions will generally produce good
garlic. Soils that have high organic matter content are preferable
to other types, since they hold moisture well and do not pack,
preventing proper bulb expansion. Heavy soils tend to prevent
the uniform expansion of the bulb resulting in irregular shapes
and rough surfaces, which are objectionable.
Garlic is shallow rooted, and deep cultivation should be avoided
as the damage to the roots will retard growth and reduce yields.
Weed removal in the plant rows should be done by hand?hoeing.
Most garlic roots grow in the upper 2 feet of soil, and the
soil should be soaked to this depth at each irrigation throughout
the growing season to ensure that the roots receive a continuous
supply of moisture. As the crop approaches maturity, watering
should cease, so that the soil will dry for harvesting. Continued
irrigation will cause rotting of the root and bulb scales.
When the tops become partly dry and bend to the ground, garlic
is usually ready for harvest. The bulbs are usually pulled and
gathered into windrows. The tops are placed uppermost in the
windrow to protect the bulbs from the sun, and the garlic is
left in the garden for a week or more to dry (or cure) thoroughly.
Curing can also be accomplished in a well?ventilated shed. The
bulbs must be thoroughly dried before being stored.
When properly cured, garlic stores well under a wide range
of temperatures. Garlic production requires a long-term commitment.
Since this crop is long-term, plant it in areas that can remain
undisturbed when spring cultivation is necessary. Of course,
at least 6 hours of sunlight is required daily.
So, that is the story on garlic production. If you want to
discourage love affairs and keep fellow gardeners at arm's length,
you may want to plant a row of garlic!