Chiku

Chiku (Manilkara zapota)

Other common names: Sapodilla, Sauh Menila, Naseberry, Nispero, Chicle, Chicle Gum, Ciku, 人心果

Chiku trees are a popular and hardy tropical fruit that grows in a variety of soil types, including notoriously poor ones. The fruit is traditionally eaten raw, and the sap was harvested to make chewing gum before the invention of synthetic substitutes.

As a perennial tree, it is a common sight in edible gardens, growing in true ground.

Sun and soil needs:

This tree does best in full sun gardens with a minimum of 6 hours of sunlight. It can also be grown in 6 or more hours of indirect sunlight, but growth will be slower and the tree may produce less fruits.

Plants do best in pots with loamy soil at least 1m deep, or in true ground. These plants are vulnerable to root rot, so ensure that your pots drain well, and that your soil has plenty of organic matter to let the roots breathe. Root rot and poor drainage will also lead to a poor fruit yield. This tree is drought-tolerant and can also tolerate salty soil.

Sowing Seeds

Seeds can be sown directly into pots or the ground. Because the plant eventually grows into a tree, it is easier to grow a few seedlings in separate pots before selecting the healthiest one to be grown in true ground.

The seedlings are generally resilient to most environmental factors but may be vulnerable to being eaten by snails or birds. Protect your young plants with a DIY cloche or netting.

Growing:

Chiku trees are steady growers but do benefit from being fed high potassium and phosphorus fertilisers once a month after its first flower to encourage flowering and thus fruiting. Regular pruning to promote airflow will keep the plant healthy and neat.

Cut stems will produce sap that can irritate the skin. Wear gloves while maintaining the plant to prevent this.

This tree can grow up to 30m high, and usually has a broad crown. The tree is best maintained at roughly 3m high for easy maintenance and harvesting.

The tree will need to be around 5 years old before it starts producing fruit if grown from seed. Air-layered plants take around 2 years to fruit.

Harvesting:

Fruits are ripe when the brown skin becomes slightly wrinkly and soft. Mushy fruits are over-ripe. Fruits can be harvested unripe then left to ripen off the tree, or harvested ripe for immediate consumption. Fresh fruit and cut stems will produce sap that can irritate the skin. Harvest the fruit while wearing gloves to prevent this.

Seeds can induce vomiting when ingested and should be removed before serving.

Propagation:

This tree is grown via seed, or via woody cuttings with rooting hormone.

Common problems & solutions:

If your plant has few to no flowers, you can fertilise the plant with fertilisers high in phosphorus and potassium. These nutrients encourage root and flower growth, which are important for the plant to produce more fruit.

Many plants require pollinators to help them fruit. Bees, butterflies, birds and even beetles transport pollen from one flower to another, pollinating your crops and increasing their fruit yield. Attract some pollinators to your garden by growing pollinator-attracting crops.

Aphids, mealy bugs, whiteflies, and spider mites often infest the plant if it has underlying problems like waterlogging. Mechanical pest control methods like pruning the infested parts are the best methods for managing these pests in the short term, but resolving the underlying problem will prevent them in the long term.

Fruit flies can lay eggs in the fruit, resulting in larvae damaging the fruit and creating spots on the skin. Wrap your fruit in netting when it starts to develop from a fertilised flower, ideally after all the petals have dropped off.

Birds and rodents may eat unripe or ripe fruit. Wrap your fruit in netting when it starts to develop from a fertilised flower, ideally after all the petals have dropped off.