Sow lamb's lettuce in August — start now for your autumn harvest

Frau Schneider asked me this week whether there was anything she could still plant. Her tomatoes are coming in, the courgette keeps producing, but the gaps between rows are slowly opening up.

"Something quick," she wrote. "Something that'll be ready by autumn."

Lamb's lettuce.

Not because it's the most exciting option. But because it works in August, when almost nothing else would bother starting. And because it keeps going until December, long after everything else has been cleared away.

Why lamb's lettuce, and why now

Lamb's lettuce is a cool-season crop — autumn and winter is where it belongs. It germinates well at 10 to 20 degrees Celsius, which is still fine in August. But it grows slowly: about eight to ten weeks to the first harvest. Sow today and you'll be picking by late September or early October.

Wait too long — mid-September or later — and the plants won't have time to size up before the first frosts arrive. They'll stay small and fragile, instead of entering the cold as the sturdy little rosettes that sail through frosty nights without complaint.

The window: early August to around the 20th at higher elevations (Zürich, Bern), up to early September in warmer valleys.

How to sow

Lamb's lettuce goes straight into the bed. No indoor starts, no transplanting.

I make a shallow groove about one centimetre deep with a finger or a stick, drop in seeds every two or three centimetres, press the soil down lightly, and water well.

Row spacing: twenty centimetres is plenty — lamb's lettuce stays flat and compact.

The most important thing for the next two weeks: keep the soil moist. Lamb's lettuce seeds germinate poorly in dry soil, and August sun dries out a raised bed quickly. Water in the morning, check again in the evening — if the surface is dry, water again. Once the seedlings are up, they need much less attention.

Thinning — but not too soon

When seedlings are about two or three centimetres tall, thin them to five to seven centimetres apart. Pull out or cut the weaker ones.

Don't start before that. Young plants offer each other a little shelter against temperature swings. Once they're established, thin away.

The seedlings you remove are edible, by the way. Small, tender, good in salad.

When to harvest

Lamb's lettuce is harvested leaf by leaf, not as a whole head. When the outer rosettes have five to seven well-formed leaves, you can take the outer leaves and the plant carries on. You can also harvest whole rosettes when you need more.

What sets lamb's lettuce apart from other salad greens: it gets better after the first frost. Cold sweetens it. A rosette that has weathered a few frosty nights in late October tastes noticeably milder and less bitter than one picked in September.

I always wait until mid-October for the main harvest. What comes before that is a previewing privilege. The real thing comes later.

What works well alongside it

If you still have space: a sowing of spinach in August follows a similar logic. Spinach germinates faster — five to seven days — but it's less frost-hardy than lamb's lettuce and needs a fleece cover to make it through November. Worth it.

Radishes can also go in now — ready in twenty days. But only if temperatures aren't regularly climbing above 28 degrees anymore, or they'll go woody and too sharp to eat.

What Frau Schneider is doing now

I told her: three rows of lamb's lettuce in the gaps between the tomatoes. One centimetre deep, water well, keep moist for two weeks.

She replied: "That's it?"

Yes, that's it. Lamb's lettuce isn't demanding. No special soil, no special position. Just don't let it dry out now, and don't sow too late.

By late September she'll probably write to tell me the bed wasn't as empty as she'd thought.

🦔 Stachi