What Makes My Jalapeno Peppers Crack on the Bush?

Normal Cracking

• Jalapenos often develop slight cracks around the top of the fruit, where they radiate out from the base of the stem. It occurs when the fruit is fully ripened, although lighter cracks often precede the deeper, more pronounced splits. Called checking or corking, the cracks are merely a cosmetic issue common to many older cultivars and cannot be corrected. It will not impact the taste, texture or quality of the fruit, but it does render them undesirable for sale in the marketplace.

Cultural Problems

• As with all peppers, jalapenos grow best in warmer areas with a long, relatively dry growing season. However, extreme heat and humidity may cause the fruit to split or crack. Jalapenos grown outdoors are less likely to develop splitting than those grown in a greenhouse, but it may be an issue in warmer, wetter climates. Covering the pepper plants with 30-percent shade cloth and watering only when the soil is visibly dry will help decrease heat and humidity around the plants, which will help preserve the fruit during very hot weather. Also, limit water to 1 inch per week so the fruit doesn't plump too quickly because fast growth encourages radial cracking, or "rain checking," around the blossom end.

Physiological Disorder

• Although few diseases routinely afflict jalapeno plants, many develop physiological disorders such as blossom-end rot. The first symptoms include dark, shiny spots on the blossom-end of the fruit, which is toward the tip. The spots later deepen, and form deep cracks or holes. It is caused by a calcium deficiency in the plant, which is caused by high heat or moisture stress. Blossom-end rot can be prevented by ensuring the soil pH is around 6.2 at planting, and by withholding supplemental irrigation during rainy weather to prevent the leaching of nutrients from the soil and damage to the roots.

Chilling Damage

• Chilling damage affects jalapenos mainly at the end of the growing season when an unexpected early frost occurs. The main symptom is moist, weeping spots, or pits, that decay and split open. No treatment for chilling damage exists once it occurs, so it must be prevented. Keep the pepper plants protected with a row cover if colder-than-average weather is forecast and pick any nearly ripe fruit before cold weather strikes to preserve as much of the harvest as possible.