Use of Sulfur Fertilizer for Vegetable Production

Using fertilizer for your vegetable garden helps make sure that your plants are getting all the nutrients they need for optimum growth and production. The need of plants for sulfur is not as commonly recognized as other plant nutrient needs. Some vegetables have high sulfur requirements that is not met by all garden soils, so the vegetable gardener needs to be aware of the signs of sulfur deficiency in plants and what to do about them.

Plants have nutritional needs just like humans and animals, of which the main ones, oxygen, carbon and hydrogen, are supplied by the water and air. But plants require many more nutrients for their best growth. According to the Rutgers Research Cooperative and Extension Fact Sheet, "Fertilizing the Home Vegetable Garden," sulfur is one of the macronutrients required for plant growth, along with nitrogen, phosphorus, potassium, calcium and magnesium. Macronutrients are nutrients that the plants take up from the soil in large amounts.

Certain vegetables have especially high sulfur requirements. Cabbage, cauliflower, kale, turnips, and radishes, all belonging to the mustard family, as well as onions, asparagus and many flowering plants need a lot of sulfur in order to thrive. If they are not getting enough sulfur from the soil, they will develop signs of sulfur deficiency.

Keeping an eye out for signs of nutritional deficiencies is essential for successful vegetable gardening. Confusingly, signs of sulfur deficiency resemble signs of nitrogen deficiency. The plants will be stunted in growth and develop "chlorosis," which makes them turn pale green or yellow. With sulfur deficiency, though, the whole plant is affected and the leaves do not die back in the early stages of deficiency.

Whether or not your garden soil is likely to require sulfur fertilizer depends on the soil in your region. If the soil in your region is sandy, your plants are more likely to suffer from sulfur deficiency. Fortunately you can test for sulfur deficiency in your garden soil or, even better, before you plant your vegetable garden by using a soil testing service. According to the National Sustainable Agriculture Information Service, most land-grant universities offer free or low-cost soil testing services to gardeners.

Sulfur fertilizers include sulfate of potash, ammonium sulfate and composts or manures. You can even address sulfur deficiency in the garden by using Epsom salt. To determine the needs for the soil in your garden, consult a soil testing service to get recommendations for optimizing the growth of your sulfur-requiring vegetables.