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PestsSerious

Aphids on Cannabis Plants

Aphids are small pear-shaped insects (usually green, sometimes black/pink) that cluster on stems and new growth, sucking sap and weakening the plant.

What it looks like

  • Clusters of small pear-shaped bugs on stems and under leaves
  • Sticky residue (honeydew) on leaves
  • Black sooty mold growing on the honeydew
  • Curled, distorted new growth

Quick diagnostic checks

1Strong water spray knocks them off mechanically
2Neem oil every 3 days for 2 weeks
3Release ladybugs for outdoor grows

Causes ranked by likelihood

1. Outdoor or near open windows

Most common

Signs

  • Grow is near outdoor access
  • Other plants infested nearby

Fix

  • Ladybugs eat 50+ aphids per day — release in the grow
  • Neem oil spray (covers eggs and adults)
  • Spray with soapy water (1 tsp dish soap per quart)

⚠️When to worry

Aphids reproduce fast. Large populations cause real damage in 2 weeks.

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