CUSTARD APPLE (Annona spp)

Common names: Custard-apple, sugar-apple, sweetsop

Custard-apple is a common name used for any of various Annona species of small trees or shrubs of the Annonaceae family: sugar-apple (Annona squamosa), sweetsop (Annona reticulata), soursop (Annona muricata) and cherimoya (Annona cherimoya).

              Species

1.   Cherimoya (Annona cherimoya)

It is a fairly dense, fast-growing, woody, semi deciduous but mostly evergreen low branched (5-9 metres tall), spreading tree or shrub. The fruits are large green conical or heart-shaped, 10-20cm long with skin that gives the appearance of having overlapping scales or knobby warts. The ripened flesh is creamy white and contains numerous hard, inedible, brown or black, beanlike, glossy seeds. The fruit pulp is sweet and mildly acidic. The fruit is rich in vitamin C, B1 (Thiamin), B2, potassium and niacin.

Cherimoya fruit                                           Cherimoya tree

  1. Sugar-apple/sweetsop (Annona squamosa)

It is a small well-branched tree or shrub that bears edible fruits called sugar-apple. It is a semi deciduous tree 3-6m tall, bole short, up to 20cm diameter.  The fruits are compound round to heart shaped, 5-10 cm diameter. The flesh is a yellowish pulp, aromatic with sugary taste, surrounds shiny, dark brown to black seeds. It is commonly found in the coastal areas at elevations up to 1100m above sea level.

Custard-apple Plant and fruit                    Ripe fruits

  1. Soursop (Annonamuricata)

This is a small, upright evergreen tree. It performs well in warm areas at altitudes of up to 1400m a.s.l. The height varies from 4–10m depending on factors such as climate, soil and crop management. The plant has large, glossy, dark green leaves. It produces a large, heart-shaped, edible fruit that is 15–20cm in diameter, yellow-green in color and has white flesh inside. When ripe, the fruit flesh is juicy, slightly acidic, whitish and aromatic. Sugars constitute about 68% of the total solids. It is a good source of vitamin B1, B2, C, calcium and phosphorus. The fruit is used for juice preparation and flavouring.

Soursop fruits

 

Ecological Requirements

Custard apples are adapted to a wide range of ecological conditions.

 

Altitude

Depends on different species:

Cherimoya: 1400-2200m a.s.l.

Sweetsop: up to1100 m asl

Soursop: up to 1400 m asl

Rainfall

The trees are only moderately drought-tolerant, requiring rainfall above 700 mm. Fruit production is poor during drought conditions.

Soils

The trees grow best in well drained soils that are slightly acidic.

 

Propagation

Seed propagation is the common method used, however cleft grafting plants bear fruits after 3-4 years.

 

Spacing is as follows for the different species:

  1. Sour sop: 6 X 7 m
  2. Sweet sop: 5 X 6 m
  3. Cherimoya: 7 X 8 m

 

Field management

Custard apple requires uniform soil moisture from flowering until harvest, therefore during dry spells, irrigation may be necessary to sustain high production.

 

Young trees bearing many fruits may need support using stakes to prevent branches from breaking. Formative pruning should be carried out when the tree is dormant the. Tipping off vigorous shoots during the growing season should be done to stimulate the emergence of flower buds.

 

Pests

Pest Symptoms / Damage Control
Aphids (Macrosiphum euphorbiae) Clusters of small black or brown soft bodied insects found on young tender shoots and underside of leaves.

They cause growth distortion by sucking plant sap.

Honey dew and sooty mould is usually present.

Use  recommended insecticides as in citrus
Fruit flies (Ceratitis capitata) The female fly lays eggs within the skin of ripening fruits.

Spots develop on the skin where eggs were laid and on hatching the larvae enter the fruit.

On immature fruits, the spots are yellow or brownish, but in older fruits soft rotting follows fruiting stage.

The attacked area becomes soft, turns brown and decays.

Maintain field hygiene through removal and destruction of fallen fruits and other debris under the tree.

Harvesting

Cherimoya

The fruits are mature when the flesh between the sections of the fruit becomes cream coloured. Fruits are perishable and cannot be stored for more than 2-5 days. Yields of up to 20 tons/ha can be achieved.

 

Soursop

Fruits are harvested when fully mature but still firm. Mature fruits ripen 3-5 days after harvest and can be stored for 2-3 days after ripening. The fruit weight can range from 0.5-5kg. Yields are 10-30 fruits/tree /year.

 

Sweetsop

Fruits are mature when the flesh between the sections of the fruit becomes cream coloured. Pick fruits carefully from the trees as they easily get damaged. Fruits are perishable and cannot be stored more than 2-5 days and this hinders commercial production. Harvest mainly during dry season. Seedlings 5 years old may yield 50 fruits per tree and older trees rarely exceed 100 fruits per tree unless hand-pollinated. As the trees get older, the fruits become progressively smaller and it is considered best to replace the trees after 10 to 20 years.

Utilization

Cherimoya is eaten fresh because the pulp does not store well and the fruit is only available fresh. Seeds are toxic and when crushed can be used as an insecticide.

 

Sugar-apple fruit is high in calories and is a good source of iron, potassium, vitamin B1 and dietary fibre. Usually the fruits are eaten fresh or used to make beverages and fruit shakes. In some countries, the flesh is pressed through a sieve to eliminate the seeds and is then added to ice cream or blended with milk to make a cool beverage.

 

Soursop is usually processed into ice creams and drinks, but fiber-free varieties are often eaten raw.