Momordica balsamina aka Balsam Apple

Momordica balsamina is also called balsam apple. It belongs to the cucumber family. Kew lists its native range as tropical and southern Africa. It also lists southwestern Arabia and Australia. It grows in the tropics, where some seasons are dry. Wild plants grow in grassland, woodland, and along forest edges. They also grow among plants on riverbanks. Sources differ on its life cycle. Kew and NC State call it an annual climber. Useful Tropical Plants says new stems grow each year from a lasting, tuberous rootstock.

This vine grows fast and climbs with tendrils. It can also trail across the ground. NC State gives a ground height of 0.33–0.5 feet [0.10–0.15 metres]. Its listed garden spread reaches 8–16 feet [2.4–4.9 metres]. That source gives vine lengths of up to 20 feet [6.1 metres]. Useful Tropical Plants gives stem lengths of about 16 feet [5 metres]. Thin stems have angles and a few hairs. Green leaves grow in turn along the stems on short stalks. Each thin leaf blade has five to seven main lobes. Smaller lobes or sharp teeth line the edges.

Small, pale yellow flowers open in summer. Each grows alone and has clear veins. Male flowers grow on longer stalks than female ones. Fruit forms in late summer or early fall. As it ripens, its warty skin turns from yellow-green to orange. Ripe fruit splits open to show seeds with sticky, scarlet coats. Flowers and fruit both add interest to gardens. The plant draws songbirds, too. NC State lists it for containers and edible gardens.

Grow balsam apple in full sun or partial shade. It prefers light, moist soil that drains well. Soil rich in organic matter helps it yield more vegetables. NC State lists acid, neutral, and alkaline soils as suitable. It gives USDA hardiness zones 9–11 and calls its care needs low. Growers most often use seeds to raise new plants. They can start seeds indoors or sow outdoors in spring. NC State reports no known insect pests or diseases. It also warns that the plant is invasive in several regions outside Africa. Its account of the plant's status in Australia differs from Kew's native-range account.

People cook the leaves and young, bitter fruits as vegetables. They also put them in soups and sauces. These food uses do not make every part safe. Ripe fruit can make people vomit and cause diarrhea. It can also harm dogs that eat it. NC State lists both fruits and seeds as poisonous parts. People have used leaves and fruit in place of soap. The plant also has uses in traditional medicine. Those uses do not prove that it is safe.