Black-Eyed Susan

Black-Eyed Susan (Rudbeckia hirta) is a North American annual or short-lived tender perennial in the daisy family, producing bold yellow-to-red flowers with a distinctive dark domed centre. Plants grow 50–90 cm tall with sturdy, branching stems that yield a near-endless succession of 8–12 cm blooms. It thrives in full sun to partial shade and tolerates a wide range of soils. An outstanding cut flower that attracts bees and butterflies throughout the growing season.

Growing

Start seeds indoors 5–7 weeks before outdoor transplanting is safe. Sow at 0.5 cm depth — seeds need light for germination, so press firmly onto moist compost rather than burying deeply. Maintain substrate at 18 °C or above; germination takes 14–21 days. Pot on seedlings once they have two true leaves. Harden off transplants for 7–10 days once night temperatures stay reliably above 5 °C, then plant out at 25–30 cm spacing. Alternatively, direct-sow at 0.5 cm depth once soil is consistently warm.

Care

Water regularly but allow the soil surface to dry slightly between waterings — plants are drought-tolerant once established. Feed with a low-nitrogen, moderate-phosphorus fertiliser when buds first appear to boost flowering. Deadhead spent blooms promptly to extend the flowering period and prevent excess self-seeding. Taller cultivars may need light staking in exposed positions. No serious pest or disease issues under good airflow conditions.

Harvest

Cut stems when the outer ray petals have just fully opened and the dark centre cone is firm to the touch. Harvest early in the day when stems are turgid. For the longest vase life, cut to just above a lateral bud to encourage replacement stems. Continue harvesting throughout the season; plants bloom until the first hard frost.

In the kitchen

Black-Eyed Susan is grown as an ornamental cut flower. Freshly cut stems are used in mixed bouquets, border arrangements, and pollinator-garden displays. Petals are edible and can be scattered over salads for colour, though the primary use is decorative.

Storing

Place cut stems immediately in clean water with a commercial cut-flower preservative. Store arrangements in a cool location away from direct heat; blooms last 7–10 days in a vase. Dried seed heads can be left to air-dry fully on the plant or hung upside-down in a warm, airy space and stored in paper envelopes for re-sowing.