Pests & diseases › Carrot Rust Fly

Carrot Rust Fly

Tiny black fly whose larvae tunnel into carrot, parsnip, celery and parsley roots. Triggered by the smell of crushed foliage.

Symptoms

  • Rusty-brown tunnels through carrots
  • Foliage turning reddish then yellow
  • Roots rotting in storage

Lifecycle

Two generations per year. Adults fly low (under 24 inches).

What to do

  • Pull damaged roots — use undamaged portion immediately
  • Bag tunneled roots — don't leave on soil

If it's bad

  • No effective home-garden insecticide

Stop it coming back

  • Floating row cover from sowing
  • 24-inch fabric barrier around bed (flies fly low)
  • Sow sparingly, never thin in warm evenings
  • Resistant varieties: Flyaway, Resistafly
  • Companion plant with onions/chives

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.