Gloriosa Daisy

Gloriosa daisy is one of the common names for Rudbeckia hirta, also called black-eyed Susan. It is a fast-growing, upright, branching plant that blooms in its first year when started from seed in early spring. The flowers have a brown or green domed center with bright yellow or orange rays, and the daisy-like flowerheads appear from summer to autumn. The pages describe the species as a whole, and cultivars can differ in height and color.

Start seed indoors in early spring, which lets the plant bloom in its first year. Seeds need light to germinate, so cover them very lightly and mist or bottom water them to avoid burying them. Light is needed for germination. Seeds sprout in 8 to 14 days at 68 to 72 °F (20 to 22 °C). The recommended method is to sow into 50-cell or 72-cell plug trays 5 to 7 weeks before planting out. Harden plants off before planting them out. Seed can also be sown directly into the garden, covered very lightly. It grows well in moderately fertile, well-drained soil in full sun or partial shade. Plants can reach 2 to 4 feet (61 to 122 cm) tall and 1 to 2 feet (30 to 61 cm) wide.

Feeding. Moderate fertility gives the best flower display, so avoid planting at lawn edges where lawn fertilizer adds excess nitrogen. Deadheading. Remove spent flowers to keep the plant blooming. Self-seeding. The plant self-seeds freely and usually stays in the garden.

Plants are susceptible to powdery mildew, snails, and slugs. Powdery mildews are a concern especially on dry soils, and young growth can be affected by slugs, aphids, and leaf and bud eelworms.