Impatiens balsamina aka Balsam

Impatiens balsamina has two names: garden balsam and rose balsam. It is part of the Balsaminaceae family. Its native range spans western and southern India and Sri Lanka. Gardeners grow it as an annual that cannot take frost. It has spread beyond gardens in many warm regions. It grows on disturbed ground and in village waste places. It also grows in open, damp sites.

Plants grow upright with few branches and soft, fleshy stems. Garden height ranges from 0.5–2.5 feet [0.15–0.76 metres]. Plants can grow taller in the wild. Mature spread reaches about 1.5 feet [0.46 metres]. The thick stems are smooth, angular, and green to red. Simple, pale green leaves grow in rings around the stems. Their shape ranges from oval to narrow and pointed. Small teeth line the leaf edges. The plant grows fast and needs little routine care.

The cup-shaped blooms may have single or double rows of petals. Flowers come in white, pink, red, purple, and mixed shades. Some blooms have spots, and the flowers have curved spurs. Blooms reach about 0.17 feet [0.05 metres] across. In seasonal gardens, flowers bloom from May until frost. In warm climates, blooms may appear all year. Each flower starts in a male phase, then can receive pollen. Insects carry pollen to the flowers. Bees, butterflies, and birds that feed on nectar visit the plant. Hairy young seed capsules turn from green to yellow. These seed cases burst when ripe if something touches them. This scatters their seeds.

Grow garden balsam in rich soil that drains well. It accepts clay, loam, and sand across a broad pH range. Keep the soil moist; do not count on drought tolerance. Full sun and part shade both suit it. Part shade works best in the St. Louis area. Sources list USDA zones 2–11, but frost kills this tender annual. Start seeds indoors six to eight weeks before the last frost. Plant outside after that frost has passed. Pinch young stems to help them grow more branches.

Garden balsam suits pots, borders, path edges, and woodland gardens. It can reseed and spread as a weed. This is more of a concern in tropical climates. Serious pests and diseases are rare. Still, bacterial wilt and southern blight can occur. People use its leaves and flowers for dye and traditional medicine. Food-use records list cooked leaves and shoots. They also list raw or cooked seeds. These records do not remove the safety concerns. NC State lists low-severity human poisoning from eating large amounts of raw leaves. It reports no contact dermatitis, a skin rash from touch. It also lists the plant as non-toxic to pets.