Growth Response and Mineral Uptake of Vegetable Transplants Growing in Composted Sewage Sludge Amended Medium.

Abstract

Six species of vegetable transplants were grown in market packs filled with peat moss, perlite and screened sewage sludge compost (equal parts by vol.). Compost was made from lime-dewatered sludge and woodchips. Seedlings were fertilized at 1, 2, 3 and 4 wks after transplanting in single, split and multiple applications of varying levels of N and K in factorial combinations. Fertilizer applications could be delayed 1 to 2 wks after transplanting without a loss of top growth. Lettuce, broccoli and cabbage plants were grown to marketable size with only N fertilizer. However, eggplants, tomato and pepper plants grew best when fertilized with both N and K. Acceptable levels of P, Ca, Mg, Md, Zn and Fe, as measured in tissues, were provided by the growth medium and tissue Cd levels wete within acceptable limits.