SUPPLEMENTARY IRRADIATION OR DUSK TO DAWN LIGHTING FOR CROPPING CARNATIONS AT SEVERAL POPULATION DENSITIES

John W. Mastalerz
Carnations were grown at population densities of 36 to 84 plants per sq meter and irradiated continuously with fluorescent lamps as a supplement to solar radiant energy or the photoperiod was extended from dusk to dawn with incandescent lamps. Plants were discarded after the first flush of flowers resulting from a single pinch were harvested. Carnations planted in mid-July flowered in 115 to 130 days when irradiated; unlighted plants required 185 to 200 days to flower. When planted in mid-December; irradiated plants flowered in 152 to 166 days, whereas unlighted plants were harvested in 175 days. Yields increased as the population density increased, but quality decreased. Fresh weight was related to the type of irradiation-flowers from plants receiving supplementary irradiation were not as heavy as flowers from plants with dusk to dawn lighting. The heaviest flowers were produced on unlighted plants.
Mastalerz, John W. (1983). SUPPLEMENTARY IRRADIATION OR DUSK TO DAWN LIGHTING FOR CROPPING CARNATIONS AT SEVERAL POPULATION DENSITIES. Acta Hortic. 141, 157-164
DOI: 10.17660/ActaHortic.1983.141.21
https://doi.org/10.17660/ActaHortic.1983.141.21

Acta Horticulturae