The Effects of Sowing Date and Root Restriction on the Yield of the Glasshouse Tomato

The effects of sowing date and the use of containers on early and total yields of glasshouse tomatoes are discussed in relation to the economic interpretation of the data, and a tentative method of determining equivalent market yield from crop yield is outlined. Assessed economically, there was little effect of the use of containers relative to direct border planting. This finding is discussed in relation to the existence of an interaction between temperature and root restriction. The equivalent market yield was greater the earlier the sowing date, and the increase in the returns obtained from early sowings was greater than the increase in heating costs involved.