What's Wrong with My Pepper Plant?

Calcium travels into pepper fruit dissolved in water, and it moves poorly once it reaches the developing end of the fruit. When soil dries out and then gets soaked, the pulse of growth outruns the calcium supply and the tissue at the blossom end collapses into a dark sunken patch. Container peppers and sandy beds show it most because they dry out fast between waterings.

Pepper pollen turns sterile when daytime highs push past 90°F. The plant aborts flowers it can't set rather than waste energy. This is why midsummer plants look healthy but produce nothing for weeks, then restart when temperatures ease in late summer.

Peppers are warm-season tropical plants that stall below 55°F at night. Flowers open but pollen never activates and the blossom drops. Early transplants set into cool soil often lose every bloom for weeks until the weather catches up.

Bell pepper skin is thin and gives little UV protection on its own. The plant relies on its own leaf canopy to shade developing fruit. When leaves drop from pests or pruning, exposed fruit bleaches to pale yellow or white, then the tissue beneath collapses and goes papery.

Peppers are heavy feeders with a shallow fibrous root system that depletes the top few inches of soil fast. When nitrogen runs short during peak fruiting, the plant pulls it back from the oldest leaves first. Yellowing starts at the base of the plant and works upward while the top stays green.

Pepper roots sit shallow and rot quickly in waterlogged soil. When they suffocate, the plant can't pull up nutrients even though the soil is wet. Yellowing spreads across the whole plant rather than progressing neatly from the bottom.

Peppers roll their leaves inward on hot afternoons to cut down on water loss. It looks alarming but is often temporary and reverses by evening. If leaves are still curled in the cool of the morning, the plant is running a real water deficit.

Dense colonies on the undersides of young leaves cause leaf edges to curl and pucker. Pepper plants push soft new growth all season, giving aphids a continuous supply of fresh tissue to target. Look for sticky honeydew residue and pale distorted growing tips.

Tomato hornworms can strip a pepper plant's foliage in a day or two. They're bright green and nearly invisible against leaves. Look for large ragged holes and dark pellet frass on the soil below before you find the caterpillar itself.

Tiny black beetles that jump when disturbed and leave a scatter of small round holes across pepper leaves. They hit transplants hardest in spring and can stunt young plants before the leaves have enough area to outgrow the damage.

Stippled, dusty-looking leaves with fine webbing on the undersides. Hot dry weather and drought-stressed peppers invite them fast. Damage can look like early yellowing before you notice the webbing or mites themselves.