Production of Soil Block Seedlings in Plug Trays for Mechanical Transplanting.

Establishing vegetables in the field using mechanical transplanters with only plant metering devices requires transplants with heavy soil blocks around the roots. An investigation was conducted to study the effects of amount of vermicompost in a soil-based potting mix and initial compaction of the mix on growth of seedlings and soil block strength for mechanical transplanting. Seedlings of Tomato (Solanum lycopersicumL.), Eggplant (S. melongenaL.), and Chili pepper (Capsicum frutenscensL.) were produced in two seasons in plastic plug trays with a potting medium in which vermicompost made up 20%–50% by volume in 60 and 100 cc tray cells. Potting mix with 20% vermicompost by volume in soil in 100 cc cells produced good growth of tomato and chili pepper transplants in season 1. Potting mix containing 20%–30% and 20%–40% vermicompost in soil in 100 cc cells produced good growth of tomato and chili pepper transplants, respectively, in season 2. Potting mix with 30%–40% and 30% vermicompost by volume in soil in 100 cc cells produced good growth of eggplant seedlings in seasons 1 and 2, respectively. The effects of initial compaction of potting mix on water requirement, plant height, and soil block strength was studied for the production of tomato seedlings. Potting mix with 30% vermicompost in 100 cc tray cells and initially compacted to the dry density of 0.88–0.90 g·cm−3was most suitable for production of seedlings of sufficient height and soil block strength for mechanical transplanting. [ABSTRACT FROM AUTHOR]