Broadcast applications of phosphate and potash will be more efficient when applied before a deep tillage operation. Recent data indicate that a band application of P at a depth of 4 or 6 inches is more effective than drill row application. This method of application will also prevent a buildup of nutrients at the soil surface under minimum tillage. Recently emerged flax is often deficient in iron during cold and wet springs. As the soil dries and warms the symptoms disappear.
Zinc deficiency can be present in addition to iron chlorosis.
As the name implies, the plants are chlorotic and the growing tip dies. After the growing tip dies, axillary buds develop to form many branches. A soil test for zinc is available from the North Dakota State University Soil Testing Laboratory. It will prove helpful in identifying soils with suspected zinc problems. For soils testing low in zinc, a broadcast rate of 10 pounds per acre zinc as zinc sulfate is suggested.