Cultivation

Container production of Black-eyed Susan

Rudbeckia hirta L.

Technology for growing Rudbeckia hirta in limited soil volume, requiring photoperiod control, precise substrate composition, and growth management to produce compact, marketable plants.

In the reference 21 varieties crop Black-eyed Susan, where this is mentioned in the description.

For container production of Rudbeckia hirta L., selected varieties with a compact habit, 23–45 cm in height and capable of flowering in 12–17 weeks, are used. The plant is an obligate long-day species: a minimum of 14 hours of light is required for flower initiation; however, increasing the day length beyond 16 hours leads to undesirable stem elongation. The optimal temperature range is 18–20 °C; temperatures below 16 °C cause leaf reddening and delayed development.

The substrate for containers must ensure effective drainage, so 20–30% clay and agroperlite are included in the mix. Due to its fibrous root system, Rudbeckia is highly sensitive to waterlogging and deep planting of the root crown, which provokes the development of root rots. During fertilization, a nitrogen level of approximately 150 ppm is maintained, as an excess of nitrogen fertilizers negatively affects flowering and stem strength.

The technology involves using pots with a diameter of at least 11 cm to prevent drying out of the root ball and the toppling of plants. To ensure crop uniformity and correct the habit when temperature control is not possible, growth regulators are applied via substrate drench.

General information about the subject — on the page Container culture.

Sources8

Varieties of Black-eyed Susan mentioned in the description

Selection based on the description text, not on official evaluation: these data are absent from registers. For specific variety details, please refer to its profile.