Potassium Deficiency in Chili Crops

A typical symptom of potassium deficiency in chili crops is the leaves turning purple and/or yellow between the veins, resulting in a blotchy appearance (Figure 1). This image shows an example of this purple blotch, which gives the foliage a very unappealing look and makes it difficult to sell at the market. The first step in correcting this condition is to determine whether or not they're actually is a potassium deficiency present. If you're unsure what steps to take after reading this article, please contact your local Texas A&M AgriLife Extension Service County Extension Agent or Horticulture Specialist for advice.

Potassium Deficiency

The Most Commonly Overlooked Problem with Growing Chili: The most commonly overlooked problem during chili growing is that many growers don’t monitor or pay attention to their levels of potassium. If they did, they’d understand how important it is to control potassium deficiency in chili crops. Potassium deficiencies lead to yellowing leaves and leaf tips and even interveinal chlorosis.

symptoms in chilli plants

Common symptoms of potassium deficiency include interveinal chlorosis, dead patches, reduced leaf size and vigor, lower plant height, weakened stems, and delayed maturity. Leaf margins may turn brown and curl under; new leaves may be small or dark green in color. As plants mature, their stems can become weak and slender. When deficient during flowering, some male flowers may drop prematurely before fertilization occurs.

causes

The most common cause of potassium deficiency is soil that lacks potassium. There are many other factors, however, that can lead to an overall shortage of potassium in plants, including temperature, drought, and pests. Farmers who work with these crops should be familiar with these conditions and how they affect nutrient absorption. By following a few best practices, farmers can avoid or minimize deficiencies for a healthier crop yield. For example, spacing seeds at proper intervals—at least 12 inches apart—and irrigating them on a regular basis can help chili plants maintain adequate levels of potassium throughout their growth cycle. These best-practices guide farmers through each step of seedling care before the growing season begins and into harvest; from here, it’s important to understand which methods will help to address any current shortages immediately.

prevention

Keep soils well-drained and evenly moist. On dry, irrigated soils, molybdenum sulfate can be applied at 0.5 pounds per acre before planting. On fields receiving 20 inches or more of rainfall per year, adequate soil moisture should prevent potassium deficiency, but occasionally potassium deficiency may occur even when there is no drought. In that case, a rate of 1 to 2 ounces per acre (1 tablespoon) will correct a deficiency if it exists. It’s best to apply potassium late in the growing season after leaves have appeared because cold weather converts much of an application into fertilizer components that are not available to plants until warmer weather arrives. If soil test levels are deficient during fallow periods, applications can help maintain good yields when crops return.

chemical control 

If your soil isn’t providing enough potassium, you can use fertilizer. Potassium sulfate and muriate of potash are readily available and come in granular or powder form. Most of these fertilizer products also have a few trace elements to go along with their single major nutrient; ensure that you get a formulation that is tailored for chili plants, as many fertilizers marketed for general garden use won’t contain adequate amounts of potassium.

[ Use fertilizers containing potassium (K)

• muriate of potash MOP
• potassium nitrate KNO3]

It's best to apply fertilizers during field preparation and at flowering.Crops take up potassium more efficiently through soil fertilization than from foliar sprays