234 Holding Tomato Transplants beyond Planned Transplant Date

Abstract

In a wet spring, transplants must often be held beyond the planned transplant date. The plants become overgrown, making mechanical transplanting difficult. We compared several ways of holding `Mountain Spring' tomato (Lycopersicon esculentum L.) transplants. Transplants were 1) planted outside on planned transplant date in late May (NH), 2) held outside for 2 weeks (HOF), 3) held outside for 2 weeks and not fertilized during that period (HONF), and 4) held in the greenhouse for 2 weeks (HGF). Throughout transplant production, half of the transplants in each holding treatment were fertilized with 100 ppm N and half with 25 ppm N from 20N-4.4P-17K or 15N-2.2P-12.3K. HONF reduced plant height 1.7 to 1.5 cm compared to HOF or HGF. Plants grown with 25 ppm N were 5 to 6.4 cm shorter than plants grown with 100 ppm N and showed symptoms of nutrient deficiency. On average, holding treatments reduced marketable yield 20% to 23% and early yield 31% to 37%, compared to NH. HOF and HGF produced similar marketable yield, early yield, and fruit size. HONF decreased early yield in 1997 and decreased marketable yield in 1998, compared to HOF. The differences between holding treatments were usually greater with 100 ppm N. Plants grown at 25 ppm N produced lower marketable and early yields and larger fruit than 100 ppm N. The best method for holding transplants among those tried here is to put them outdoors and continue fertilizing as during transplant production.