The sugar apple (Annona squamosa) is a small, semi-deciduous tree prized for its unique, delicious fruit. It is also commonly called sweetsop or custard apple due to its distinctive flavor and texture. Native to the tropical Americas and the West Indies, the fruit has a thick, knobby rind composed of separate segments. When mature, the flesh inside is creamy white to light yellow, fragrant, and possesses a sweet, custard-like taste.
Climate and Soil Requirements
The sugar apple thrives in tropical and subtropical climates, requiring a consistently warm environment for optimal growth and fruiting. These trees are sensitive to cold, performing best when temperatures remain between 70°F and 95°F. While a mature tree can briefly tolerate temperatures as low as 28°F, frost exposure below 32°F can cause significant damage or death, especially to young specimens.
The tree requires full sun exposure, needing at least six to eight hours of direct sunlight daily for healthy growth and maximum fruit production. Moderate to high humidity is also beneficial, with levels of 70% or higher ideal during flowering and fruit-setting periods. The soil must be well-drained, as the trees are intolerant of continuously wet conditions that can lead to root rot. A sandy loam soil is preferred, and the tree tolerates a wide pH range, from slightly acidic (5.5) to neutral (7.5).
Starting the Tree: Propagation and Placement
A sugar apple tree can be started either from seed or by planting a commercially purchased grafted tree. While seedlings are easy to grow and may begin fruiting in two to four years, the resulting fruit quality is unpredictable and may not match the parent tree. For assured, true-to-type fruit quality, purchasing a grafted tree from a reputable nursery is the recommended method.
When planting, select a location that receives full sun and has adequate air circulation, keeping the tree away from structures or power lines. The planting hole should be dug twice as wide as the root ball to allow for root expansion. If planting a grafted tree, ensure the graft union remains above the soil line to prevent the scion from rooting. Allow a spacing of 10 to 15 feet between trees to accommodate the sugar apple’s naturally bushy and spreading growth habit.
Young trees can be successfully grown in containers, which is beneficial in cooler climates where the plant needs to be moved indoors for winter protection. For the first few years, a 15 to 20-gallon container will be sufficient. Loamy soil amended with organic matter provides the best medium for initial establishment.
Essential Care: Watering, Fertilization, and Pruning
Consistent moisture is necessary for the sugar apple, particularly once the tree begins to flower and set fruit. The soil should be kept evenly moist during the active growing season, but never saturated. Since the tree is semi-deciduous and may enter dormancy, watering should be significantly reduced during the cooler, drier winter months.
Young trees benefit from frequent applications of a balanced fertilizer, such as a 10-10-10 formulation, applied every four to six weeks during the growing season to encourage vigorous growth. Once the tree matures and begins bearing fruit, the focus shifts to a balanced formula with less nitrogen, often applied two to three times per year. Foliar sprays containing minor nutrients—specifically zinc, manganese, and boron—are often necessary to prevent deficiencies and support healthy fruit development.
Pruning should be performed annually in the early spring, just before the new growth flush begins. The goal of pruning is to remove any dead or weak wood, thin the canopy to improve light penetration and air circulation, and maintain a manageable height of around 8 to 12 feet. Since sugar apples produce fruit on new growth, removing about one-third of the previous year’s vegetative growth will stimulate new fruiting wood.
Knowing When to Harvest
Determining the moment to harvest a sugar apple can be challenging, but there are several clear indicators of maturity. The fruit will undergo a noticeable color shift, changing from a deep green to a lighter green, yellowish-green, or sometimes a pale blue-green depending on the variety. The segments that make up the rind are the most reliable indicator, as they will begin to swell and slightly separate, showing a faint white or yellowish line between them.
A gentle squeeze will confirm the fruit is ready to pick; it should yield slightly, feeling firm but not rock-hard. Harvesting is best done when the fruit is mature but still slightly firm, which typically occurs in the late summer or early fall. The fruit should be carefully cut from the branch using shears, leaving a small piece of the stem attached. Allowing the fruit to fully ripen on the tree often results in it falling and splitting open, which attracts pests and causes spoilage. Sugar apples picked at the firm, mature stage will fully ripen within a few days at room temperature.