Gynandropsis gynandra aka African Spider Flower

Gynandropsis gynandra is a straightforward annual to grow from seed. It germinates readily in 5-14 days at 25 degrees C when surface-sown or barely covered with soil. It performs best in full sun with well-drained fertile soil and tolerates both dry and moderately moist conditions. It is frost-tender and should be sown or transplanted only after all risk of frost has passed.

This annual herb typically reaches 25-60 cm tall under average garden conditions, but can grow to 1.3-1.5 m in fertile, well-watered soil. Its C4 photosynthetic system drives rapid growth in warm, sunny climates. The plant completes its full life cycle — from germination through seed set — within a single growing season.

Gynandropsis gynandra is native to tropical and subtropical Africa. It has naturalized across a wide range from sea level to 2400 m altitude, spanning sub-Saharan Africa, South and Southeast Asia, and parts of the Americas. It has been introduced to the Caribbean, continental North America, and Hawaii, where it is considered invasive.

The plant requires adequate soil moisture throughout its vegetative growth period. It is drought-tolerant once established but is sensitive to waterlogging and flooding. Both dry and moderately moist soil conditions are acceptable, making it fairly adaptable in terms of water management.

Gynandropsis gynandra grows best in deep, well-drained, fertile soil with high humus content. It tolerates both light sandy and medium loamy soils. Preferred soil pH is 5.5-7.0 (mildly acidic to neutral). Good drainage is essential; the plant does not tolerate waterlogged conditions.

Full sun is required. The plant cannot grow in shade and reaches optimal productivity at high light intensity. It is adapted to the open, sunny environments of tropical agricultural land and disturbed habitats.

Optimal growth occurs between 18-25 degrees C. The plant is frost-tender and will not survive freezing temperatures. It is suited to USDA hardiness zones 8-12 (UK zone 9) as a perennial, and can be grown as a warm-season annual in cooler climates.

Sow seed after the last frost in spring, surface-sowing or covering lightly (about 1 cm deep) in rows 30 cm apart. In temperate climates, start indoors in a greenhouse. The plant grows rapidly through spring and summer, flowering July to August in temperate conditions. Harvest leaves throughout the vegetative period; uprooting the whole plant or selectively cutting upper leaves prolongs the harvest. Plants self-seed freely, so deadhead or remove spent plants if spread is not desired.

Flowers are small and white, and may turn rose-pink with age. The fruit that follows is a slender, spindle-shaped capsule up to 12 cm long and 8-10 mm wide, containing 100-150 small round black seeds (1.0-1.5 mm in diameter). In temperate regions, blooming occurs July to August.

No named cultivars or horticultural varieties were documented in any source accessed. The species is primarily grown from locally adapted landraces across Sub-Saharan Africa. Active breeding programs are studying genetic variation across African and Asian accessions for agronomic improvement of mineral content, yield, and stress tolerance.

Gynandropsis gynandra is primarily an outdoor plant suited to warm climates (USDA zones 8-12). It thrives in full sun, well-drained fertile soil, and warm temperatures (18-25 degrees C). In cooler regions it is grown as a warm-season annual, started under glass and transplanted after the last frost. Note that the species is considered invasive in the United States and Pacific regions; check local regulations before growing it outdoors.

Propagation is exclusively by seed. Surface-sow or lightly cover seeds (about 1 cm deep) in rows 30 cm apart. In temperate regions, start in a greenhouse in spring; seeds germinate in 5-14 days at 25 degrees C. Direct sowing outdoors after the last frost is standard practice in warm climates. Plants self-seed freely once established.

Common pests include flea beetles, cabbage sawfly, pentatomids (stink bugs), locusts, and root-knot nematodes. Fungal disease pressure is generally low in well-drained conditions. Peer-reviewed work has explored chemical management (using insecticides such as Ambush and Ripcord) as well as breeding programs for pest resistance.

Gynandropsis gynandra produces small white to rose-pink flowers typical of the Cleomaceae family, which are generally pollinated by insects. The flowers are attractive relative to the plant's modest size and likely draw a range of insect visitors. No detailed pollinator studies were found in the sources accessed for this species specifically.

Leaves and young shoots are widely consumed across Sub-Saharan Africa as a nutritious leafy vegetable, typically boiled or added to stews and prepared with groundnut paste in Kenya, Uganda, and Tanzania. Leaves are dried for off-season storage. In Southeast Asia, leaves are traditionally fermented or braised. The plant is nutritionally dense: roughly 4% protein, 127-484 mg vitamin C per 100 g, high beta-carotene, folic acid, and calcium. Multiple peer-reviewed studies confirm its importance as a climate-resilient food crop; 93.9% of participants in one survey identified it as an important edible plant.

Traditional uses span multiple African and Asian cultures: root decoctions for fevers, root juice for scorpion stings, leaf poultices as rubefacients for rheumatism, leaf juice for ear pain, seeds as anthelmintics, and the whole plant used for snake bites. PFAF rates medicinal value at 2/5. Peer-reviewed research has confirmed antifungal activity of ethanol extracts against Microsporum canis and Trichophyton mentagrophytes, supporting traditional Ugandan topical use for scalp ringworm. The plant is also rich in antioxidants and secondary metabolites of interest for antimicrobial and anti-inflammatory applications.

Seeds contain 17-19% oil with fatty acids including palmitic, stearic, oleic, and linoleic acids. The plant has documented insect-repellent and anti-tick properties and is used as an intercrop to protect adjacent plants. It can also serve as animal fodder. Note that PFAF's other-uses rating of 0/5 appears to exclude traditional agroecological uses documented in other sources.