Parthenium integrifolium

Germination

Sow in a cold frame in autumn/winter or sow indoors 6-8 weeks before last expected frost. For cold frame sowing, sow 6mm deep into moist well-drained seed compost, place in a cold frame, allow natural winter cold to offer ideal conditions for germination to occur as the weather warms in spring. Indoors, place seed in between some moistened kitchen paper and put in a zip-lock type bag and place in a fridge to cold stratify, 4°C is ideal, leave for 2-4 weeks. Remove seeds from fridge, carefully remove seeds from the bag and sow 6mm deep into seed compost ideal temp. for germination is 21°C. Transplant indoor grown seedlings when large enough to handle to 8cm pots and grow on. Acclimatise and plant out after danger of frost has passed.

Growing

Prefers a wide range of soils in full or partial sun. This plant thrives in full sun.

Cultivation

Deadhead after flowering to prevent volunteer seedlings. Propagate by seed or via softwood cuttings taken in summer.