vegetable · leafy green

Lettuce — Cos

The upright one, with a crisp elongated heart. Cos takes about six weeks and stands up to a warm spell better than a soft butterhead.

Lettuce — Cos seedling
Seedling
Mature Lettuce — Cos
Ready to pick
Thrives
12–18°C
Water
High
Difficulty
Beginner
Ready in
40–45  days
Spacing
25cm apart
Containers
Yes

How to plant it

  • Plant 25cm apart. Cos grows upward rather than outward, so it takes less room than it looks.
  • Water at the base, not over the top. Water sitting down inside that tight upright heart is where rot starts.
  • Ready at about six weeks, when the heart feels firm if you squeeze it gently.
  • Take a few outside leaves earlier if you want something off it sooner. The heart carries on regardless.
  • Handles heat better than most lettuces, which is why it is the classic summer salad one.