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Subtropical Fruit Choice Wide---
From Avocado to
Tamarind
by Robert J. Knight, Jr., and Julian W. Sauls
Subtropical fruits number over a hundred and range from avocado and
citrus to soursop and tamarind. Thus the information in this chapter has
to be general rather than specific and you should seek more detailed
advice from your county Extension office. Nurserymen can be most helpful
too, as can experienced gardeners, garden clubs, or other specialized
groups such as the rare fruit organizations active in Florida and
California.
Fortunately, cultural requirements for most subtropical fruits do not
differ from those of other shrubs, trees or vines grown for fruit,
ornament, shade or other specialized use. In fact the outstanding
ornamental value of most fruit crops fits them admirably for a dual role.
Because they come from many parts of the world with varied
environmental conditions, subtropical fruit crops differ in the degree of
cold they can withstand and in soil and moisture requirements. Some are
adapted to warm-temperate conditions, and others are tropical plants which
will tolerate brief cold spells and thus survive winters in the warmest
parts of the continental United States.
When you select fruits to plant around your home, choose those known to
grow well in your locality. Otherwise you may go to a lot of trouble to
grow a plant that may prove disappointing despite your best efforts. Your
own personal preferences, tempered by knowledge of what grows well in the
area, should determine what you plant.
Most tree fruits should be planted 12 to 20 feet apart and away from
the house, walks, drives, and power lines. Those tropical fruits listed as
small trees or shrubs at the end of the chapter can be planted somewhat
closer. Where there is significant danger of cold damage, plant
subtropical fruits in the warmest part of the yard, which generally is the
south side of the house.
Most failures in growing fruit trees at home can be attributed to poor
transplanting or poor care. Commercial fruit growers routinely transplant
fruit trees with almost no failures.
Good preparation of the planting hole is essential. Dig the hole only
as deep as and about a foot wider than needed to accommodate the root
system. Regardless of your soil type, it would probably benefit from the
addition of liberal amounts of organic matter such as rotted manure,
compost or peat.
For bare-root plants, prune off dead or damaged roots. Make a cone of
soil in the center of the hole and set the plant on it, carefully spread.
ing the roots out in the hole. For container-grown plants, remove the
container and set the plant in the hole.
In either case, set the plant at the same depth it was growing in the
nursery or container. Fill the hole three-fourths full of soil. Then fill
with water to settle soil around the roots and eliminate air pockets.
After the water drains through, finish filling the hole with Soil, then
water again. A ring of soil a few inches high around the planting hole can
be used to form a watering basin during the first year.
At planting, bare-root fruit trees should be pruned to balance the top
with the reduced root system, which requires removing about a third of the
top. Most people are reluctant to prune this heavily, but it's for the
good of the tree. If you're unsure about doing the job right, have the
nursery where you bought the tree do it for you. Container-grown plants
are not usually pruned since they have an intact root system.
Training
Initial training of the fruit tree
is done at planting to assure that the tree takes the desired shape. For
example, the growing tips of branches are pruned off to force branching.
Even so, most subtropical fruit trees are not trained appreciably, but
simply allowed to develop naturally.
Mature trees are pruned to remove dead or damaged wood, or to eliminate
limbs that may interfere with traffic in the yard. Such pruning can be
done at any time of year.
Pruning cuts should be clean and close to the trunk to avoid leaving
stubs which enable wood-rotting organisms to enter the tree. Protection
with pruning paint is recommended if the cut is larger than an inch or so
in diameter.
Subtropical fruit trees are not in such prominence that they require
"special" fertilizers as yet. You can- not run down to the garden center
and pick up a bag of "Kiwi Special" or "Atemoya and Cherimoya Food".
Fortunately, subtropical fruits will grow just as well on a complete,
balanced garden fertilizer such as 6-8-8, 10-10-10, or 12-12-12. However,
if your area has alkaline soils or soils known to lack specific
mironutrients such as iron, manganese or zinc, these may need to be
supplied.
Newly planted trees should not have fertilizer until they resume active
growth after transplanting. Then, fertilize sparingly and frequently until
they mature and begin to produce fruit. Using 10-10-10 as an example,
young trees should receive about a pound of fertilizer per year of tree
age, that is, 1 pound in the first year, 2 in the second, and so on. Total
fertilizer for the year should be divided into several applications so
young trees receive some fertilizer every 2 to 3 months.
Mature, bearing trees can be fertilized at double that rate, or 2
pounds per year of tree age. Thus, a 10-year-old tree would receive 20
pounds per year, which would be split into 3 applications-early spring,
early summer and early fall. Fertilizer can be spread on the ground under
the tree and then watered in.
Lime may be needed in some cases to raise the soil pH so it is suitable
for optimum tree growth. However, liming should be based on a soil test
and recommendation from the county Extension agent. Occasionally, some
fruit trees may need certain micro-elements, particularly in very sandy
soils or alkaline soils. Micro-elements are included in some fertilizers
and are also available in nutritional sprays which are applied separately
as foliar (leaf) sprays. In all cases follow recommendations of your
county agent.
Mulches
Mulches around fruit trees help in
weed control and water conservation. They also reduce lawn mower damage to
tree trunks since you don't need to mow close to the trees.
In some cases, organic mulches can lead to fertilizer deficiencies as
the micro-organisms that decompose them rob nutrients the tree could use.
They also contribute to increased cold damage by inhibiting radiation of
ground heat to the tree. In other cases, organic mulches increase the
incidence of diseases such as foot rot and root rot. For these reasons, we
recommend clean cultivation instead of mulches for citrus, avocado, lychee
and some other fruits.
Mulches from your yard could include leaves and grass clippings. Or you
can obtain sawdust, wood chips, pine bark, gravel and other mulches from
local nurseries. A lot of gardeners don't understand about watering
plants. This is one reason why so many fruit trees die shortly after
transplanting. Too little water causes the tiny root hairs to die, and the
leaves then wilt for lack of water. On the other hand, too much water
forces air from the soil, again causing the root hairs to die for lack of
oxygen, and the leaves will wilt. For best results, water fruit trees
infrequently but thoroughly.
Frequent, shallow waterings cause shallow rooting. A shallow-rooted
fruit tree is subject to drought and poor growth. Consequently, when you
water, water long and water well. Apply water only as fast as the soil can
absorb it and keep watering until the soil is wet at least a foot down.
Newly transplanted trees need a good soaking every 2 to 4 days until
they are well established. Mature trees need water every 7 to 12 days,
depending on the climate and soil type. Since sandy soils don't hold much
water, they require watering about once a week, while clay soils will go
several days longer before drying out.
Fruit trees growing in the lawn area will compete with the lawn for
fertilizer and water. In such situa- tions pay particular attention to
needs of both tree and lawn. The tree will compete much more aggressively
than the grass. The grass will soon begin to thin out and may
disappear completely once the tree begins to create heavy shade.
Cold protection often is required for many subtropical fruits.
Young trees are more susceptible to cold than large, mature
trees, but also easier to protect. Banking a mound of soil around the
trunk of a young fruit tree will keep the rootstock and trunk alive even
if the top should freeze. Pull the bank down in spring after cold danger
is past.
Small trees can be covered with blankets, paper or plastic to prevent
freezing. Lawn sprinklers have been turned on trees, but too much water
can cause problems for the root system and ice can cause limb breakage. In
some cases, a frame covered with clear polyethylene can be built around
the tree to form a mini-greenhouse. Some slow-burning heating materials
are available and work quite well; check with your county Extension agent
or nurseryman.
Most subtropical fruits have enough insect and disease problems to make
growing them troublesome at times. You need to learn the potential pest
problems and bow to control them. To do this requires a little effort on
your part in order to be able to recognize the damage before it becomes
serious, identify the insect or disease responsible, and take effective
remedial action before the damage pro- gresses too far to control.
Containers
Many subtropical fruits can be
grown in containers in areas where freezes occur each year. The size and
mobility of the containers allows the plants to be moved indoors during
winter months. Thus, the plants are treated pretty much as houseplants
with regard to water, fertilizer, humidity, light, and pest control.
As with houseplants, water container plants infrequently but
thoroughly. Take care to acclimate the plants to the different conditions
when they are moved outdoors in spring or indoors in fall. Plants going
outdoors should be moved to a shady spot for a couple of weeks before
being exposed to full sunlight. Reverse this process when moving them
indoors in fall.
When plants are indoors, put them in areas receiving the most natural
light possible. Keep them away from heaters, doors and heating ducts.
Because of lower humidity indoors, you need to increase the humidity
around the plants, by misting or other means.
Growing plants in containers or patio tubs will reduce plant size due
to the reduced volume of soil in which they're growing. Even so, the plant
may soon grow too large to bring indoors. When this happens, prune back
the plant severely.
Following is information about some fruits that can be grown in many
parts of the Southern and Southwestern States. The letters Wt
(Warm-temperate), St (Subtropical) and T (Tropical) are intended to give
an approximation of temperature requirements of each species. However,
other factors, such as amount of rainfall and the time of year that rain
comes, will also determine whether a particular fruit can be grown in your
area.
Avocado
(Persea americana). St. T.
Shade tree with rough dark bark
suitable for growing bromeliads and or- chids. More than one variety
should be planted together for cross-pollination. Plant locally adapted
varieties. Will not tolerate heavy, poorly drained soils.
Banana
(Musa acuminata, Musa hybrids). T.
Rootstock may survive
light freezes. Giant, treelike herb, planted for ornament where cold
precludes fruiting. Many varieties have been introduced but the most
widely grown are Cavendish (a commercial crop), Apple (sometimes called
Lady- finger), and Orinoco (also called Horse banana and good for
cooking). The starchy cooking banana called Plantain is very tender to
cold.
Carambola
(Averrhoa carombola). T.
Tree varying from small to
large. Characteristic 5-angled fruit of yellow or deep orange color varies
from sour to sweet and is pleasantly aromatic. Plant grafted varieties
(Golden Star, Mih Tao). Cross-pollination aids fruit set.
Carob
(Ceratonia siliqua). Wt.
Small tree with attractive
dark green leaves that prefers a Mediterranean climate, very dry in summer
with rains during winter. Trees may be male or female, so more than one
should be planted to ensure fruiting. The brown, leathery pods are rich in
sugar and furnish a chocolate substitute.
Cattley
guava (Psidium cattleianum). St.
Shrub or small
tree with beautiful mottled trunk and glossy dark green leaves. The small,
round fruit, bright red or yellow-colored, is subacid in flavor and may be
eaten fresh or made into jellies or jams. Plants grow readily from seed
and are normally so propagated.
Feijoa
(Feijoa sellowiana). Wt.
Shrub. Compact, cold-resistant
and most attractive, selected varieties such as Coolidge fruit well
without cross-pollination, but seedlings may not do so. Flowers are
edible. Fruit can be eaten fresh, and makes a firm jelly.
Fig
(Ficus carica). Wt.
Small tree. Adapted to a wide range
of climates, fig will not tolerate nematodes. Where these are a problem,
heavy mulching and occasional application of an approved nematicide,
according to pre- scribed rules, will help. Lemon, Brown Turkey, and
Celeste varieties are recommended.
Guava
(Psidium quajava). T.
Small tree. Somewhat weedy unless
pruned to shape it, the guava can be attractive, particularly when in
bloom. Fruit of some seedlings and selected varieties is excellent for
jelly, while that of varieties such as Ruby x Supreme and Indian Red is
good to eat out-of-hand. Fruit flies are a problem where abundant.
Jaboticaba
(Myrciaria cauliflora). St.
Shrubbery tree. Grows slowly
but where well established produces abundant crops of black, grapelike
fruit excellent to eat fresh or use in jellies or wines.
Kiwi,
Yangtao (Actinidia chinensis). Wt.
Vine. Not
successful in warmer parts of Florida, this deciduous species is sensitive
to nematode damage. Flowers of named varieties (females, for example
Hayward) must be pollinated in order to fruit, so a pollinator should grow
nearby. Because of its excellent quality this fruit should be planted
wherever it can be grown well.
Longan
(Dimocarpus longan) T.
A lychee relative that bears
clusters of attractive, smooth, golden brown, sweet-flavored fruit that is
less tart than lychee fruit. The tree is less demanding as to soil and
moisture than lychee, and makes a shade tree of stately proportions.
Kohala, from Hawaii, bears large fruit ot good quality.
Loquat
(Eriobotrya japonica). Wt.
Small tree. The dark green,
deeply ribbed leaves of this tree combined with its tendency to produce
fragrant creamy-white flowers over a period of months make the loquat a
universally valued ornamental. The excellent fruit quality of grafted
varieties such as Wolfe, Gold Nugget (Thales), and Champagne make these
worth the effort needed to find them. Fruit is excellent eaten fresh, but
may also be made into pie, jam, and jelly.
Lychee (Litchi chinensis). T.
Tree.
Somewhat finicky, demanding slightly acid, well-drained soil, with
abundant moisture and no salts in soil or water, this tree covered with
its bright red fruit is a sight to remember where it grows well. Long
popular in Southeast Asia, the fruit has many American devotees. It may be
eaten fresh or dried like raisins. The most dependably productive
varieties are Sweetcliff and Mauritius.
Mango
(Mangifera indica). T.
Tree. Of the many existing
varieties, take the time to select one that appeals to you: Carrie, Irwin,
Glenn, Keitt, and Tommy Atkins are outstanding. Blooming trees can cause
allergic reactions; do not plant near bedroom windows or air conditioner
intake. The mango is one of the world's most popular fruits.
Passion fruits (Passiflora edulis, purple,
and P. edulis f. flavicarpa, yellow). St. T.
Vines are
ornamental. The purple-fruited form is sensitive to nematodes and
soil-borne fungus disease, but withstands more cold than the
yellow-fruited form, which is disease-resistant. Self-pollinating types
should be planted where possible, otherwise fruit production may be
sparse.
Pineapple
(Ananas comosus). T.
Perrenial herb. This bromeliad makes
an attractive house plant where outdoor temperatures are too low for it.
The plant can be moved to a porch or patio during warm weather. Given
enough light it will eventually flower, then produce a fruit of fine
quality provided conditions are warm enough.
Pomegranate
(Punica granatum). Wt.
Small tree that tolerates extremes
of heat and alkaline soils, but thrives under a wide range of conditions.
Needs full sun for best performance. Wonderful and Sweet are the varieties
best known for their fruit quality. Other varieties are grown primarily as
ornamentals.
Tamarind
(Tamarindus indica). T.
Large tree related to the carob,
with very acid fruit in pods. Pulp of the tamarind, an essential
ingredient of many chutney recipes, also is used to make a refreshing
ade-like drink. Where the climate is warm enough for it, this tree is easy
to grow.
Annonaceous Fruits
Atemoya
(Annona cherimola x A. squamosa). T.
Moderate-sized tree, a
hybrid of the cherimoya and the sugar-apple, that combines the excellent
fruit quality of the cherimoya with the fitness for low elevations of the
sugar-apple. Flowers abundantly in warm weather, but may need to be
hand-pollinated to assure fruit set. Desirable varieties are Kaller
(African Pride) and Bradley. Others are under test.
Cherimoya
(A. cherimola). St.
Small tree adapted to high elevations
in tropical South America, producing a large green fruit with a sweet,
delicately aromatic pulp that surrounds many smooth dark seeds. Does not
grow well in southern Florida but is more successful in California where
it withstands temperatures as low as 25°F.
Soursop or
guanabana (A. muricata). T.
Small tree,
very sensitive to sudden cold spells, that bears a large, rough fruit with
a refreshing acid flavor that is excellent in drinks and sherbets. Should
be planted in a sheltered location.
Sugar-apple
(A. squamosa). T.
Small tree that bears a soft-pulped,
many-seeded fruit similar to the cherimoya but without that fruit's fine
aroma. Grows well at sea level in southern Florida and other areas of
similar climate.
Cactus Fruits
Indian fig
(Opuntia ficus-indica). Wt.
Large treelike cactus with smooth
flat joints and few spines. Yellow flowers in spring are followed by large
red or yellow fruit. Bristles can be irritating; handle fruit with care.
Prefers a dry climate and does not thrive in humid situations.
Citrus
Calamondin
(Citrus blancoi). Wt. St.
Small tree of great ornamental
value that grows and fruits well in small containers. The fruits resemble
small oranges but are acid and not good to eat out-of-hand. Flavor is
excellent for drinks and marmalades.
Grapefruit (Citrus paradisi). St.
Medium
to large-size tree, excellent for shade and for growing orchids and
hanging plants, providing up to 300 pounds of excellent breakfast or juice
fruit per year. Varieties include Duncan (white, seedy pulp, excellent
flavor), Marsh (white, seedless) and Ruby (pink pulp, seedless).
Kumquat
(Fortunella japonica). Wt.
Shrub or small tree, very
cold-tolerant, extremely attractive when in fruit. Nagami is the most
common variety, with oblong fruit, deep orange in color having a thick
edible skin and an acid pulp. Adapted to candy making or use in
marmalades.
Lemon (Citrus limon). T.
Small tree that
remains in active growth all year and thus is less cold-resistant than the
tangerine or even the orange. Of irregular growth habit, the lemon must be
pruned from time to time to promote an attractive shape. Eureka, Lisbon
and Villa Franca all bear similar fruit, of acceptable commercial quality;
Eureka makes a smaller tree than the others. Novelties are Meyer with a
less acid fruit, and Ponderosa, which bears very large, mild-flavored
lemons.
Lime (C. latifolia). T.
Small tree that
bears large, juicy green fruit useful in drinks, pies, and as a condiment.
The most disease-resistant and dependably productive variety is the
seedless-fruited cultivar known as Tahiti, Persian, or Bearss. Less
resistant to disease and cold, and bearing smaller seedy fruit of a
delectable flavor, is the Key or Mexican lime, C. aurantifolia. (A hybrid
between the Key lime and the the Limequat produces a valuable acid fruit
in areas too cold for the lime itself. Eustis fruits well in the open as
well as in containers.)
Orange (C. sinense). St.
Tree of moderate
size, probably the most popular of all citrus fruits, available in a
number of varieties that ripen at various seasons. Hamlin is one of the
earliest, ripening in November, followed by Pine- apple and Washington
Navel, which ripen from December to February, and then by Valencia, which
ripens in April or later and can be "stored on the tree" into the summer
months.
Tangelo (C. reticulata x C. paradisi). St.
Tree, hybrid between tangerine and grapefruit, bearing fruit which
combines characters from both parents. Vigorous and cold-resistant.
Several varieties are available. Minneola and Orlando need to be planted
near other citrus trees for cross-pollination. The Temple tangor (C.
sinensis x C. paradisi) bears a sweet, juicy fruit similar to tangelos.
Tangerine (C. reticulata). St.
Tree of
attractive growth habit, fairly resistant to cold, whose beauty is
enhanced by the waxy, deep orange-colored fruit in season. Dancy ripens
before Christmas, as does Clementine, which can be "stored on the tree" in
good condition for months. Closely related are the cold-hardy and early
dwarf Owari Satsuma, which ripens from October to Christmas, and the Kara,
Honey and Kinnow mandarins.
Persimmons
Black-sapote
(Diospyros digyna). T.
A tropical Mexican and Central
American persimmon that grows well in southern Florida. The dark brown
pulp is rich in vitamin C, and also a source of calcium and protein. It
was important in the diet of Central America before Columbus.
Japanese persimmon (Diospyros kaki). Wt.
Small tree, attractive even when out of fruit with its large, hairy
leaves; highly ornamental when the bright orange-colored fruit is
ripening. Trees grafted on D. lotus or the native American D. virginiana
are available. Fuyu bears fruit that is non-astringent even before fully
ripe. Fruit of Hachiya and Tane Nashi is astringent until fully ripe, but
then delectable. in dry climates, fruit may be sun-dried to make a
fine-flavored product.
Robert J. Knight, Jr., is Research Horticulturist, Agricultural
Research Service, Miami Fla, Julian W. Sauls is Extension Horticulturist,
University of Florida, Gainesville..
Courtesy USDA | 