Chrysanthemum response to polyaspartic acid in peat-based media and mineral soil

This study evaluated the growth and flowering of hardy chrysanthemum (Dendr anthema x morifolium) in peat-based media and mineral soil treated with Ami sorb - a polyaspartic acid product. Growth and flowering response was evalu ated in three experiments - two in peat-based media (Promix BX (R)) and one in mineral soil (Sassafras sandy loam). In the first, Amisorb was applied biweekly, beginning at planting at 0.03 and 0.06 mL/5-gal pot. Chrysanthemu ms were fertilized weekly with 300 mg L-1 20-20-20. The second experiment c ompared biweekly Amisorb applications at 0.02 and 0.04 mL/2-gal pot. Plants were fertilized at each irrigation with 100 or 200 mg L-1 20-20-20. No sig nificant differences in dry weight or flowering resulted from Amisorb in ei ther experiment. Flowering and dry weight were significantly greater for 20 0 mg L-l 20-20-20 than for 100 mg L-1 20-20-20 applied with each irrigation . In the mineral soil experiment Amisorb was applied weekly at a rate of 0. 06 mL/5-gal pot with a fertilizer solution consisting of 300 ppm 15-15-15. Amisorb did not significantly increase chrysanthemum blossom number and dry weight per plant in mineral soil.