We recently received several calls reporting blossom end rot of tomatoes (Figure 1). Although blossom end rot is caused by deficient supply of calcium to the developing fruit. The occurrence of this physiological disorder often relates to inconsistent supply of water. As a general rule, vegetables require 1-1.5 acre-inches of water per week. Since there is no rain in high tunnels, all the required water should be applied through irrigation. How does one determine if enough water has been applied to vegetables? This article provides some ideas. The first information needed is the irrigated area. For example, tomatoes are growing in a 30 × 96 high tunnel with 6 beds that are about 4 feet wide. Then the irrigated area is about 2,304 square feet (6 × 4 × 96 = 2,304). An acre has 43,560 square feet. So the irrigated area is roughly 2,304 / 43,560 = 0.05 acre.[Read More…]
