Natal plum
Also known as
Large num-num, Big num-num, Amatungulu, Num-num hedge, Carissa
Keep this plant’s care guide close at hand.
Get the appAbout Natal plum
Carissa macrocarpa, commonly known as Natal plum, is a dense, evergreen, spiny shrub native to South Africa’s coastal dunes and thickets. Its glossy, leathery, deep-green leaves and showy, star-shaped white flowers—often fragrant at night—lend year-round ornamental appeal. In warm climates it blooms and fruits intermittently, producing oval, crimson, plum-like berries that are edible when fully ripe, with a tangy-sweet flavor reminiscent of cranberry and strawberry. Mature plants typically reach 1–2 m (3–6 ft) high and wide, forming excellent hedges, security plantings, or salt-tolerant seaside screens. Natal plum thrives in sandy, well-drained soils and tolerates drought, wind, and salt spray once established. It bears sharp, forked spines and exudes a milky latex; while ripe fruit is safe to eat, other plant parts can be irritating or toxic if ingested. Compact cultivars like ‘Boxwood Beauty’ offer reduced thorniness and a tight habit, making the species a versatile choice for containers, urban gardens, and low-maintenance landscapes in frost-free to lightly frosty regions.
Taxonomy
Properties & Requirements
How to care for Natal plum
Water
Water deeply but infrequently. After planting, keep soil evenly moist for 6–8 weeks to establish roots. Thereafter, allow the top 2–3 inches (5–7 cm) of soil to dry before watering again; mature plants tolerate drought but fruit better with periodic moisture. In containers, irrigate until water drains, then let at least half the pot volume dry between waterings. Reduce frequency in cool seasons. Always prioritize sharp drainage—soggy soil promotes root issues and reduces flowering.
Light
Full sun yields the heaviest bloom and fruit—aim for 6–8 hours of direct light daily. It tolerates bright, dappled shade, especially in very hot inland sites, but flowering and fruiting will diminish. Indoors, place at a south- or west-facing window or supplement with high-output grow lights 12–14 hours daily. Strong light also tightens growth and reduces thorniness. Salt and wind tolerant on coasts; provide a windbreak in exposed, inland locations.
Nutrients
Carissa macrocarpa is a light feeder. In-ground plants benefit from a single application of a balanced, slow-release fertilizer (for example, 8-8-8 or 10-10-10) in early spring, plus a light top-up in midsummer if growth is pale. Container specimens respond well to a half-strength, balanced liquid feed every 4–6 weeks during active growth. For better flowering and fruit set, favor slightly higher potassium. Avoid high nitrogen, which promotes lush, thorny growth with fewer fruits. On alkaline soils, supplement with iron or micronutrients to prevent chlorosis.
Temperature
Best between 16–29°C (60–85°F). Avoid prolonged temperatures below 5°C (41°F); brief, light frosts near −2°C (28°F) may cause tip burn but established plants often recover. Overwinter container plants indoors in bright light if your area drops below 5°C. Heat tolerant with adequate moisture and airflow. Suitable for USDA Zones 9b–11 outdoors; in cooler zones, grow in pots and shift outside after danger of frost, acclimating to sun gradually.
