Pest problems of cucumber, pumpkin and squash

Powdery mildew

  • Plant varieties that are resistant or tolerant to powdery mildew.
White powdery mildew on leaves of cucurbit plant
Powdery mildew


  • Plant varieties that are tolerant or resistant to virus.
  • Remove weeds in the field.
Virus symptoms on cucurbit leaves
White virus growth on squash fruit
Virus on squash fruit

Angular leaf spot and anthracnose

  • Plant resistant varieties.
  • Use drip irrigation to keep leaves dry. Do not work in plants when wet.
  • Remove and destroy or bury infected plants after harvest.
  • Do not plant cucumber, pumpkin, squash or melon in the same location for 2-3 years.
  • Do not save seed from infected plants.
Green leaf with brown spots and holes from angular leaf spot
Angular leaf spot
Anthracnose symptoms on cucurbit leaf

Squash bug

  • Remove plant debris around garden during garden season and fall.
  • Remove and destroy eggs.
  • Remove or knock off squash bugs into container of soapy water.
  • Trap squash bugs under boards and remove in the morning.
Squash bug infestation on squash leaf
Squash bugs
Squash bug eggs on squash leaf
Squash bug eggs

Squash vine borer

  • Plant butternut squash, cucumbers, melons, and watermelons as they are not normally attacked by squash vine borers.
  • Make a second plant of summer squash in early July.
  • Use yellow pans of water to detect when adult moths are first active
  • Use row covers when adult moths are first active (late June/early June). Leave for 2 weeks and then remove.
  • Remove and destroy plants killed by squash vine borers.
Squash vine borer bug on squash leaf
Adult squash vine borer
Squash vine borer caterpillar causing damage to a squash vine
Squash vine borer caterpillar
Mesh row cover on squash crop to keep out insect pests
Mesh row cover

Michelle Grabowski and Jeff Hahn

Reviewed in 2018

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