Leafy greens and brassicas · Easy
Lettuce
Lactuca sativa
Staple crop; rotations.
- EC (mS/cm)
- 1.2–1.8
- pH
- 6.0–7.0
- Cycle
- 30-35 d (protected)
- Difficulty
- Easy
Sound origin
Lactuca sativa
It descends from wild lettuce (Lactuca serriola), found from Europe to Central Asia by way of North Africa. Grown in ancient Egypt, it has also been cultivated in Europe since very early times.
Source: Wikipedia
What it provides nutrients
Per 100 g, raw · Lettuce, raw
- Rich in vitamin K
- Rich in vitamin A
- Source of vitamin C
- Source of vitamin B9
% of an adult’s reference intake (EU Regulation 1169/2011). “Source of”: at least 15 % per 100 g, “high in”: at least 30 % (thresholds of EC Regulation 1924/2006).
Key steps
- Stagger sowings every 1 to 2 weeks.
- ≈ 20 cm between heads; tighter for baby leaves.
- UF/IFAS cycle measured in protected production: longer outdoors.
In which system?
| Tower | NFT | Growing medium | Kratky |
|---|---|---|---|
Approximate calendar
| Sowing | Mar., Apr., May, June, July, Aug., Sept. |
| Plants | none |
| Harvest | Apr., May, June, July, Aug., Sept., Oct. |
Garden, patio, balcony: Belgian and northern French climate, earlier farther south. Estimates to adjust with your own dates.
Frequently asked questions
Lettuce in hydroponics: what pH?
Recommended pH: 6.0–7.0 (Oklahoma State HLA-6722 benchmark). Measure every day at the same time and correct in small doses, after adjusting the EC.
Lettuce in hydroponics: what EC?
Recommended electrical conductivity: 1.2–1.8 mS/cm (Oklahoma State HLA-6722 benchmark).
Lettuce: which hydroponic system?
Best suited: the vertical tower, NFT and the Kratky method. Staple crop; rotations.
Lettuce: when to sow in Belgium?
Indicative window for a garden, patio or balcony in Belgium or northern France: March, April, May, June, July, August, and September. Adjust with your own dates.