FACTORS AFFECTING THE GROWING-ON STAGES OF LETTUCE AND CHYRSANTHEMUM IN NUTRIENT SOLUTION CULTURE

Lettuce and chrysanthemum crops were successfully grown and harvested in solution culture.
Optimum growth rates were achieved at a solution temperature of ca. 24°C and a solution conductivity of ca. 1000 micromhos during the vegetative stage of chrysanthemum growth (long-day phase). Reducing the optimum rooting temperature subsequent to root initiation favoured root development.
The use of a heated solution in association with a low night air temperature produced a very favourable response.
At 7°C flower harvest was delayed by only 6 days, while quality of bloom was improved.
There was little response to additional solution aeration.
Reproductive growth of chrysanthemum was favoured at SC levels in the region of 2000 micromhos.

Fresh weight per head and hearting were improved in the lettuce cultivar Ravel at a temperature of 25°C. Satisfactory growth was obtained at SC levels up to 5500 micromhos, but the optimum level was ca. 2000 micromhos, where hearting was significantly better than at higher or lower SC levels.

Symposium on Research on Recirculating Water Culture

J.V. Morgan, A.T. Moustafa, A. Tan

https://doi.org/10.17660/ActaHortic.1980.98.26