Furthermore, the quality of vegetables will be very poor. Fruits, such as cucumbers, will be small and misshapen. Tomatoes may develop blossom-end rot and salad crops, such as celery, may have tough fibers. There are critical periods of growth when water stress can be most detrimental. It is imperative that a good moisture supply be maintained during seed germination and seedling emergence from the soil.
Specific vegetables have periods of growth when a good supply of water is essential.
For example, sweet corn needs an abundant supply of water when the silks and tassels are forming for good pollination and well-filled ears. Vine crops, such as cucumbers and squash, must be supplied with water during flowering and early fruit development. As fruit development progresses, water absorption declines, so less water is required. On the other hand, there are periods in the growth of some vegetable crops when water should be withheld. For example, as muskmelons reach maturity, they develop more sugar under dry conditions.