An experiment was conducted to clarify the effect of concentration and application frequency of nutrient solution on growth and vase life of chrysanthemums cv. ‘Seikonohana’ in sand culture.
Five treatments were designated among combinations of 3 levels of nutrient concentration and application frequencies. Base nutrient solution (1S) was applied every day (No. 1) and twice a week (No. 2). Nutrient solution of 3 times strength of 1S was applied twice a week (No. 3), once a week (No. 4) and that of 6 times strength once a week (No. 5). Concentration of minor elements, however, was kept constant in all treatments. The feeding duration with these solutions was from July 27 to flowering.
Plant height at flowring and days from pinching to flowering were not affected by treatments. The fresh weight and root dry weight were less at No. 2 and No. 4, where total amount of fertilizer applied was less. The vase life was improved slightly at No. 2 where the least amount of fertilizer was applied.
Contents of total-N and K in leaves were less at No. 2 and No. 4. However, P, Ca, Mg and Na in leaves were not affected by treatments.
Contents of NO₃-N, K, Ca and Mg, and EC values of sand solution at the end of the experiment were less at No. 2 and No. 4. However, there was no clear effect of treatments on P and Na, and pH of sand solution.
As a result, it is considered that applications of nutrient solution of high concentrations, such as 3 and 6 times strength of 1S, every 3 or 6 days are practical when nutrient solution is applied in sand culture, as well as application of 1S every day.