Possibly the most common fruit in the world (at least in
temperate climates), the apple comes in a wide variety of sizes and
colors. Though a temperate fruit, a select few varieties can be
grown in subtropical and tropical climates.
Description: A deciduous tree to about 15-25ft. Blossoms occur in
spring and in most varieties are quite ornamental.
Hardiness: Frost hardy.
Growing Environment: The average apple tree needs 750-1000 hours
of chilling each winter. This is defined as temperatures between
32F-45F. Temperatures below 32F have no effect on chilling hours,
while temperatures above 45F have a negative effect, resulting in
the tree needing additional chilling hours for proper flowering. A
few varieties of apples have been developed that need less than 100
hours of chilling and in some cases, through several manual methods,
trees may be coaxed into flowering without the temperature dropping
below 60F. Most so-called low chill apples, if untended, will
require 200-300 hours of chilling. In tropical climates,
some sort of manual pruning is a must for fruit production. Low
Chill Varieties Anna - The most well-known of the low chill
varieties, the Anna produces nicely sized red fruits similar to the
golden delicious from which this variety was developed. Needs
pollination from another variety. Dorsett Golden - Yellow skinned
apple that is often seedless. Needs pollination from another
variety. The main technique for fruit production employed in
tropical climates that don't meet chilling requirements is manual
defoliation of the leaves. By seasonally pruning off all of the
leaves on a tree, the apple is fooled into believing that natural
defoliation has occurred due to winter, which causes chemical
hormone changes in the plant that lead to the onset of flowering.
The method is simple, but effective, and if done properly can yield
2-3 crops per year. In rarer cases, less-tropical apple varieties
that have higher chilling requirements can be grafted onto the
"tropical" apples and through defoliation, can be coaxed into
Propagation: Most varieties are grafted, but apples can be grown
from seed, and seeds are a source of new varieties.
Uses: Eaten fresh, juiced, and used to prepare all sorts of
Native Range: The apple is believed to be native to the Caucasus
mountain region in Southeastern Europe and Western Asia. The apple
was historically one of the first fruits to be cultivated.