Pests & diseases › Aphids

Aphids

Tiny sap-sucking insects, green, black or grey. Cluster on shoot tips, undersides of leaves and flower buds. Sticky honeydew below.

Symptoms

  • Curled or distorted young leaves
  • Sticky honeydew on leaves and stems
  • Sooty black mould growing on the honeydew
  • Ants farming the aphids for honeydew
  • Stunted growth on tender new shoots

Lifecycle

Active from April to October in the UK. Females reproduce without mating, so colonies explode in warm spells.

What to do

  • Blast off with a strong jet of water early in the day
  • Rub off small colonies with finger and thumb
  • Encourage ladybirds, lacewings, hoverflies — plant calendula and yarrow nearby
  • Spray with diluted soft soap solution, hitting leaf undersides

If it's bad

  • Pyrethrum-based sprays (organic certified) for heavy infestations
  • Systemic aphicides — last resort, never on flowering crops bees visit

Stop it coming back

  • Don't over-feed with nitrogen — soft sappy growth attracts them
  • Inspect new plants before bringing them home
  • Companion plant with chives, garlic and nasturtiums (sacrificial)

Crops it goes for

Plan the plot, track every sowing, cook the harvest

Sowing reminders and harvest forecasts for your own frost dates, the Seed Tin, Scan Centre for any label or packet, and the Potty Mouth Garden Club. Free to start.