Can you grow mache hydroponically? Yes. Mache, also called corn salad or lamb’s lettuce (Valerianella locusta), suits cool hydroponic and indoor setups. Seed germinates at 41–68°F (5–20°C) and goes dormant above 70°F (21°C), so keep it cool. Expect slow sprouting in 10–14 days, then harvest small rosettes about 5–8 weeks after sowing.
Key takeaway: Mache is a slow, cold-loving salad green. Success comes from cool water and air, patience during germination, light feeding and cutting rosettes before warm weather makes the plants flower.
| Mache need | Target | Source |
|---|---|---|
| Germination temperature | 41–68°F (5–20°C) | Johnny’s Selected Seeds; USU Extension |
| Dormancy risk | Above 70°F (21°C) | Johnny’s; USU Extension |
| Days to sprout | 10–14 days | Johnny’s Selected Seeds |
| Best growing temperature | Not above 75°F (24°C) | USU Extension |
| Spacing | 3–4 in (8–10 cm) | USU Extension |
| Plant height | 2–5 in (5–13 cm) | UC Master Gardeners |
What Is Mache and Why Grow It?
Mache is a small rosette salad green with a mild, nutty flavor, according to Utah State University (USU) Extension. It is native to southern Europe and also goes by corn salad, lamb’s lettuce and fetticus. UC Master Gardeners of Santa Clara County note that it grows only 2–5 inches (5–13 cm) tall, which makes corn salad a neat fit for shallow trays, rafts and countertop systems.
Because the plants are small and cold tolerant, mache fills the winter gap when many greens struggle. It pairs well with other cool crops covered in our vegetables to grow indoors in winter guide.
What Temperature Does Mache Need to Germinate?
Lamb’s lettuce germinates best when the root zone stays between 41°F and 68°F (5–20°C). Johnny’s Selected Seeds warns not to sow once soil passes 68°F (20°C), and both Johnny’s and USU say seed goes dormant above 70°F (21°C). A warm heat mat, which helps tomatoes, can stop corn salad completely. Germinate it in a cool room instead.
- Cool room or basement: ideal for corn salad trays in fall and winter.
- No heat mat: extra warmth can push seed into dormancy.
- Even moisture: keep plugs damp, never soggy, for the full two weeks.
If seed still fails, work through our hydroponic seeds not germinating checklist.
How Long Does Corn Salad Take to Sprout and Grow?
Be patient. Johnny’s says mache germinates slowly in 10–14 days. USU Extension says leaf harvest can begin two to three weeks after emergence or transplanting, and transplants need five to six weeks to grow before planting out. Most growers cut full rosettes roughly five to eight weeks after sowing, depending on temperature and light.
How Do You Grow Mache Hydroponically Step by Step?
Treat lamb’s lettuce like a slow, cool lettuce. The steps below adapt extension garden advice to a home hydroponic system.
- Sow 3–5 seeds per rockwool cube or plug, about 1/4 in (6 mm) deep, as USU suggests for soil.
- Keep trays at 50–68°F (10–20°C) and moist until sprouts appear.
- Thin to the strongest seedling when plants show 3–4 true leaves.
- Move plugs to a raft, NFT channel or Kratky jar once roots show.
- Space plants 3–4 in (8–10 cm) apart.
- Keep air and water cool, ideally under 75°F (24°C).
- Harvest leaves or whole rosettes once plants are 2–3 in (5–8 cm) tall.
A shallow Kratky method container or a small deep water culture tote works well, because mache uses little water.
How Much Light and Fertilizer Does Lamb’s Lettuce Need?
Corn salad needs full sun outdoors and bright, even light indoors, but only light feeding. USU Extension advises fertilizing sparingly. In hydroponics, that means a mild leafy-green solution rather than a strong fruiting formula. Start at the low end of the range you use for lettuce and watch for pale leaves before raising strength.
For starting points on strength and pH, see our hydroponic lettuce EC guide. Lamb’s lettuce rosettes grow low, so keep lights at a distance that gives even coverage without heating the canopy.
Why Does Mache Bolt and How Do You Prevent It?
Lamb’s lettuce bolts when weather warms and days lengthen. UC Master Gardeners say it goes to seed in early spring as temperatures rise, and USU notes that high summer heat reduces growth and quality and causes flowering. Indoors, keep the grow area cool, avoid running hot lights in a small space and sow new rounds every two weeks.
- Keep it cool: under 75°F (24°C) air and water.
- Succession sow: USU suggests a new sowing every two weeks.
- Harvest early: cut whole rosettes as soon as a flower stem appears.
The same heat triggers affect other greens. Our lettuce bitterness and bolting timeline explains the signs.
How Do You Harvest and Store Corn Salad?
Cut individual leaves once they are about 4 inches (10 cm) across, or cut the whole plant at 2–3 inches (5–8 cm) tall, as USU Extension recommends. If you take leaves only, new ones form at the center. USU says mache keeps in the refrigerator for five to seven days. Wash it gently, because the tender rosettes trap grit and bruise easily.
In hydroponics there is little grit, which is one reason corn salad is pleasant to grow indoors. Rinse anyway before eating.
FAQ About Mache
Is mache the same as corn salad?
Yes. Mache, corn salad and lamb’s lettuce are names for Valerianella locusta.
Why are my corn salad seeds not germinating?
It is often too warm. Seed goes dormant above about 70°F (21°C).
Can lamb’s lettuce grow in winter?
Yes. USU says young plants tolerate 32°F (0°C) and it can overwinter.
Does corn salad regrow after cutting?
If you harvest outer leaves, new leaves keep forming at the center.
What does mache taste like?
USU describes a mild, nutty flavor.
Sources
- Utah State University Extension — How to grow lamb’s lettuce in your garden
- Johnny’s Selected Seeds — Mâche (corn salad) key growing information
- UC Master Gardeners of Santa Clara County — Mâche
- Photo credits (Wikimedia Commons, edited with titles): Corn salad, spring, close up by Unknown (CC BY-SA 3.0); Temple Sowerby, Acorn Bank, Mizuna and lettuce seedlings – geograph.org.uk – 7625183 by Michael Garlick (CC BY-SA 2.0); (MHNT) Valerianella locusta – inflorescences and Leaf by Didier Descouens (CC BY-SA 4.0); Deepwater Aquaponics Floating Rafts Growing Lettuce, Basil and Arugula by Alabama Extension (CC0)