The soursop tree is a tropical plant that can reach heights of 9 m (30 feet). It will not grow in the UK. It produces a large, edible fruit with an inedible, prickly skin. The soursop will tolerate almost any soil type but needs constant warmth. It does well with regular watering and fertilisation.
Select a site for planting the soursop tree that gets full sun and has a constant temperature above freezing. Any amount of frost will damage a soursop tree. The site should have well-draining but moist soil.
Cover the planting site with 5 cm (2 inches) of organic compost and till it into the ground with a garden tiller or shovel at a depth of 15 cm (6 inches). Soursops require soil rich in organic material. Do this in the spring.
Dig a hole in your planting site that is large enough to accommodate the root ball of the soursop seedling, or one that is twice the width of the container and just as deep. Lower the soursop into the hole and fill it with soil.
Apply 227 g (1/2 lb) of 10-10-10 fertiliser to the soil around the plant per the package directions. Repeat the fertiliser application quarterly. When the soursop is two years old, increase the application to 454 g (1 lb), quarterly. If the tree is three years old or older, apply 1.36 kg (3 lb) of the fertiliser quarterly.
Water until the soil settles and the fertiliser dissolves.
Apply a 7.5 cm (3 inch) layer of organic mulch around the base of the tree, extending to the drip line or the widest part of the tree's foliage. Do not let the mulch touch the trunk of the tree itself. Replenish the mulch throughout the year, especially after a rain. The mulch will protect the roots from dehydration.
Water the soursop frequently enough to keep the soil moist to the touch.