Photos and text by Debbie Roos
, Agricultural Extension Agent.
This problem is occuring on a local organic farm in Rudbeckia. The same plant can have both normal flowers and deformed flowers. The affected cultivars include ‘Indian Summer’ and ‘Goldilocks’. The “toothy grin” appearance of the flowers may make you smile but otherwise are unmarketable.
Fasciation is abnormal plant growth that occurs when the apical meristem, which normally produces cylindrical tissue concentrated around a single point, becomes elongated perpendicularly to the direction of growth. The resulting tissue growth may be flattened, crested, or elaborately contorted. Fasciation may occur in the stem, root, fruit, or flower head.
A number of factors can cause fasciation, including a mutation in the plant cells, bacterial infection, mite or insect attack, or chemical or mechanical damage. It can also be genetic. With so many potential causative agents, it is difficult to provide a management recommendation. Perhaps the grower could try a new seed source. The grower should maintain good records to see if the problem occurs only in these varieties.
Fasciation is not always considered a problem. The cockscomb celosia (Celosia argentea var.cristata) is an example of a flower with inherited fasciation and is grown because of its unusual flower heads (see photo at bottom of page).
Return to Crop Problems
This page last updated June 14, 2006.