Multi-rack tray system for off-season greenhouse nursery raising

In this study, already developed multi-rack tray system (MRTS) was experimentally evaluated for raising offseason winter nursery of selected ornamental plants such as marigold and calendula during the extreme winter conditions of Jan, 2007. MRTS with three stacks was constructed and installed inside a small poly house to maximize the inside space utilization for commercial nursery raising applications. The objective of using MRTS is to produce more plants from the same greenhouse, which will lower the cost per plant of nursery raising. Experiments were also conducted by raising the nursery plants on the ground of a control polyhouse and in open field condition for comparison. Complete environmental and plant data was recorded for 27 days of experimentation. The experiments showed that there was about 80–85 per cent germination and almost uniform growth in each tray proving that MRTS can be effectively used for raising three times more nursery plants from the same greenhouse. Germination inside the control greenhouse was also very good (80–82%) but slightly lesser than MRTS. However, poor germination (48–50%) and very slow growth was observed in the open field.