Variety traits

Plant height — black-eyed susan, cone flower

Rudbeckia hirta L.

The height of Rudbeckia hirta is measured as the distance from the soil surface to the point of attachment of the flower head and varies from less than 45 cm in dwarf forms to 100 cm or more in tall varieties.

In the reference 5 varieties crop Black-eyed Susan, where this is mentioned in the description.

For this crop, the most typical height range is 60–90 cm. The trait is closely related to structural stability: excessively elongated plants, often suffering from an excess of nitrogen and a lack of light, are prone to lodging under the influence of wind or precipitation.

Habit control is carried out by pinching the apex of the main stem when the plant reaches 15–20 cm, which stimulates branching and the formation of a compact bush. Photoperiodic conditions and the level of nitrogen nutrition also have a significant impact on height.

General information about the subject — on the page Plant height.

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.