Sudden Wilt

Just before your cantaloupes, cucumbers, squashes, watermelons, and pumpkins are ready to harvest, suddenly they wilt and die, taking your crop with them.

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Unlike slow wilts caused by lack of water (or too much water), or vascular diseases, such as Verticillium wilt and Fusarium wilt, sometimes the leaves of melon, cucumber, pumpkin, cantaloupes, and other cucurbits and cotton suddenly and completely droop. This sounds like sudden wilt.


Sudden wilt is a soil borne fungal disease that occurs after heavy irrigation on hot, sunny days. Contrary to what you might expect, moisture-saturated soil combined with hot sun can cause sudden wilt, also known as parawilt. This is a result of the imbalance between water uptake and water loss, combined with certain fungi.


Sudden wilt symptoms

Sudden wilt starts out as yellowing of the crown leaves, followed by total collapse of the entire plant. Death soon follows. If you dig up an affected plant, the roots will be straw-colored or darker than normal. There are three different fungi responsible for sudden wilt and each one has unique symptoms:

• Pythium spp. - appears as brown root rot
• Acremonium cucurbitacearum - corky bands on discolored roots
• Rhizopycnis vagum - upper portions of the taproot turn reddish and corky

Sudden wilt treatments

There are no chemical controls against sudden wilt. Careful water management, proper plant spacing, and the removal of crop residue after harvest can help reduce the chance of sudden wilt occurring in your garden. Monitor your cucurbits for signs of sudden wilt near the end of the growing season. Good drainage and 2- to 3-year crop rotations can help prevent this disease from wiping out your cucurbit crops, and be sure to allow the soil to dry out completely between waterings.