Corn Salad – Growing Guide

Overview

• Name: Corn Salad (also known as Lamb’s Lettuce, Mâche)
• Botanical Name: Valerianella locusta
• Plant Family: Caprifoliaceae (sometimes categorized under Valerianaceae in older classifications)
• Native to: Europe, parts of North Africa, and southwestern Asia

Description

Corn salad, also known as lamb’s lettuce or mâche, is an annual leafy vegetable grown for its small, tender rosettes of spoon-shaped leaves. These leaves typically form a low, compact clump measuring about 10–20 cm (4–8 in) tall and wide. The foliage is soft, bright to dark green, and has a mild, nutty flavor. As the plant matures, it produces slender, branching stems bearing small, pale blue to white flowers clustered at the tips. These flowers produce small, dry, one-seeded fruits (known as nutlets) which form in tight, rounded seed heads. Corn salad has a shallow root system and prefers undisturbed growth, making it well suited to direct sowing.

Although primarily a cool-weather crop, some improved cultivars offer moderate heat tolerance, though plants tend to bolt rapidly in warm conditions. It is commonly grown in spring and autumn, but in temperate zones it can be overwintered outdoors with row covers or in unheated greenhouses. In mild climates, it may even self-sow and naturalize in garden beds.

Interesting Facts

1. Historically, corn salad was foraged rather than cultivated. European peasants would gather it from fields after the grain (corn) harvest, hence the name “corn salad.” Over time, French gardeners began domesticating and selecting varieties with more uniform, tender leaves, transforming it into the popular salad green seen today.
2. In France, corn salad is called “mâche,” where it has long been a favorite among gourmet chefs. Its subtle sweetness and delicate texture make it an ideal base for premium salads. Chefs pair it with ingredients like goat cheese, toasted nuts, or citrus dressings to highlight its gentle, nutty undertones.
3. Thanks to its natural cold hardiness, corn salad can be harvested well into winter under row covers or in unheated greenhouses in many temperate climates. Gardeners often appreciate how little space it requires, fitting easily into small beds or containers for off-season fresh greens.
4. Nutritionally, corn salad is rich in vitamins A and C, folate, and essential minerals such as iron and potassium. It also contains vitamin E and some omega-3 fatty acids. Its mild flavor and crisp texture make it a great addition to mixed salads, especially when combined with tangy or bitter greens to provide balance.
5. Historically, corn salad was valued as a medicinal herb and was used in folk medicine as a mild diuretic, to “purify the blood,” and to support digestion. It contains phenolic compounds with antioxidant and anti-inflammatory properties. These constituents may support immune function, reduce oxidative stress, and contribute to cardiovascular and metabolic health when consumed as part of a balanced diet. Corn salad continues to be appreciated in European culinary and herbal traditions for both its flavor and its nutritional value.

Basic Growing Information

Corn salad is a cool-season crop that thrives in temperatures between 5–18°C (41–65°F). Optimal growth occurs within this range, promoting tender leaves and a mild, nutty flavor. Temperatures above 20°C (68°F) can lead to bolting and smaller rosettes. It’s best to sow seeds in early spring or late summer/early autumn to avoid heat stress. In colder climates, using cloches or row covers can extend the harvest into winter.

Corn salad prefers fertile, well-draining loamy soil enriched with organic matter. It tolerates a soil pH range of 6.0–7.0, which is slightly acidic to neutral. Regular, moderate watering is essential to maintain consistent moisture, especially during dry periods . While it tolerates light shade, full sun in cool weather encourages quicker growth and fuller rosettes.

• Sun Requirements: Full sun to partial shade
• Water Requirements: Moderate; keep soil consistently moist but not waterlogged.
• Soil Types and Properties: Prefers fertile, well-draining loamy soil enriched with organic matter.
• Soil pH: Ideally 6.0–7.0
• Pot Size for Container Growing: Use containers at least 15–20 cm (6–8 in) in diameter. Shallow, wide containers are suitable for multiple rosettes.

Planting

• Best Time to Plant:
  • Climates with freezing winters: Sow in early spring as soon as the soil can be worked, or in late summer to early autumn for an autumn or winter crop.
  • Climates with milder winters: Late summer and autumn sowings often yield winter or early spring harvests. In these regions, corn salad can be sown directly outdoors or under cover for extended harvesting.

Note: Check gardening calendars for the best planting times in your location

• Spacing: 5–10 cm (2–4 in) between plants; 15–30 cm (6–12 in) between rows
• Seed Sowing Method: Sow seeds directly into the ground; starting in trays is possible but less common due to the plant’s small size
• Seed Sowing Depth: About 0.5–1 cm (0.25–0.5 in) deep
• Time to Harvest: Approximately 5–8 weeks from seed planting to usable leaves.
• Mature Height/Spread: 10–20 cm (4–8 in) tall; 10–20 cm (4–8 in) wide per rosette
• Grown From: Seeds

Care and Maintenance

• Watering Tips: Keep the soil evenly moist but not waterlogged. Water at the base of the plants with a gentle flow. Mulching with straw or compost helps conserve moisture and reduce weed competition around the low-growing rosettes.
• Fertilization: Enrich the soil with well-rotted compost before sowing. Corn salad has modest nutrient requirements; a balanced organic fertilizer or compost tea applied every few weeks typically suffices. Over-fertilizing can lead to overly lush leaves that may lose flavor. Aim for gradual, steady growth rather than rapid leaf expansion.
• Pruning: Pruning isn’t usually necessary. If older leaves start to yellow or plants bolt, remove the affected portions to keep the bed tidy and discourage pests or disease. When harvesting leaf-by-leaf, snip outer leaves to extend the plant’s production. Full rosettes can also be cut away at soil level.
• Support: Because corn salad plants are small and form tight rosettes, they do not need staking or other support. Row covers or cloches might be used to shield them from frost or pests, but otherwise no structural supports are required. Keeping weeds down is the main concern for proper airflow.

Growing Difficulty

• Easy to Grow

Growing Tips

• Succession sow corn salad every two to three weeks in cool weather to maintain a steady supply of tender leaves. Begin sowing in spring as soon as temperatures reliably stay above 5°C (41°F). For a fall or winter crop, start in late summer or early autumn, using row covers or cold frames if frosts arrive early. Succession sowing can continue until about 6–8 weeks before the first expected hard frost.
• Interplant corn salad among taller vegetables that won’t shade it too heavily. Its compact growth habit fits neatly between slower-growing or widely spaced crops like broccoli or tomatoes. This maximizes garden space and may even shield corn salad from direct heat during the warmest periods. Corn salad also grows well in containers or shallow trays, which can be moved or protected as needed.
• Harvest leaves when they’re young for the most tender texture. If you notice plants forming flower buds, pick the entire rosette promptly to prevent bitterness. A quick rinse in cool water removes grit, and gentle drying preserves the delicate leaf structure, making them table-ready for fresh salads.

Companion Plants

• Good companion plants include: Radishes, carrots, beets, peas, lettuce, onions, bush beans, and marigolds (which won’t overshadow the low-growing rosettes and may help repel pests or enrich the soil)
• Avoid planting near: Large, fast-growing leafy crops (e.g., sprawling squash), cucumbers, and potatoes that could compete for sunlight, crowd out the small corn salad plants, or increase disease risk

Common Pests and Diseases

• Pests:
  • Slugs and Snails – Use natural barriers, handpick at dusk, set traps, or consider organic pellets; avoid excessive moisture to discourage them
  • Aphids – Rinse off with water or apply insecticidal soap if severe; neem oil and encouraging beneficial insects like ladybugs can also help
  • Flea Beetles – Row covers and sticky traps can reduce damage
  • Leaf Miners – Floating row covers can exclude adults; remove affected leaves to reduce spread

• Diseases:
  • Damping Off – Avoid overwatering; sow in well-draining soil
  • Downy Mildew – Ensure proper airflow; water early in the day
  • Leaf Spot – Remove infected leaves promptly; rotate crops if the problem persists

Harvesting

Harvest Time: Start harvesting as soon as rosettes reach about 8–10 cm (3–4 in) wide, typically 5–8 weeks after sowing. In mild climates or under protective cover, you can continue harvesting through winter and into early spring. Pick leaves or whole rosettes once they appear plump and vibrant. Harvest before flower stalks develop, as leaves may become bitter after bolting.

Harvesting Tips: Use clean scissors to snip outer leaves, leaving the central growth for continued production. Alternatively, cut entire rosettes at ground level if you want a single, larger harvest. Rinse leaves gently to remove soil or debris, then spin or pat them dry before using raw in salads or lightly cooked dishes. Harvest in the morning when leaves are crisp and cool for optimal texture and flavor.

Storage: After harvesting, gently rinse the corn salad leaves in cool water to remove soil and debris. Carefully spin or pat them dry with a soft cloth or paper towel. Store the cleaned leaves in a perforated plastic bag or an airtight container in the refrigerator’s crisper drawer. Under these conditions, corn salad will remain fresh for approximately 1–2 weeks. For longer-term storage, consider briefly blanching the leaves before freezing, keeping in mind that this process may slightly alter texture.

Propagation

Produce New Plants From: Seeds (direct sowing is most common)

Culinary Uses

Corn salad’s delicate, slightly sweet flavor and tender texture make it a cherished component in fresh salads, often referred to in culinary contexts as “mâche.” Because of its subtle taste, it pairs wonderfully with other greens, especially those that have a sharper or bitter flavor. For example, combining it with endive, radicchio, or watercress yields a balanced mix of sweet, crunchy, and piquant elements. Its leaves are best used raw, as cooking can diminish their mild flavor and soft consistency.

Toss corn salad with a simple vinaigrette—olive oil, vinegar, a pinch of salt, and perhaps a hint of Dijon mustard—to highlight its natural sweetness. Adding sliced pears, apples, or citrus segments introduces a refreshing burst of fruitiness, while nuts like walnuts, hazelnuts, or almonds bring complementary richness and crunch. In French cuisine, corn salad often appears in elegant starters or side dishes, sometimes with goat cheese or smoked salmon for a refined presentation.

If you do choose to cook it lightly, a swift sauté or wilting in a warm pan can suffice, but typically only a brief heat application is recommended. Its leaves can also be layered into sandwiches, wraps, or even used as a garnish for soups, adding a fresh, green accent. Because corn salad is quite perishable, refrigerate it immediately after picking, storing it with a slightly moist paper towel in a breathable bag. However it’s served, corn salad contributes a gentle, nutty flavor and a tender bite to the plate, setting it apart from the more robust lettuces and greens.

In conclusion, corn salad (mâche) offers a mild, sweet alternative to more assertive greens, thriving in cool weather and demanding little space. With consistent moisture, moderate sunlight, and timely planting, you can enjoy a continuous supply of this delicious, tender leafy green—perfect for salads, garnishes, and light culinary creations.

References

• Valerianella locusta “Medaillon” | cornsalad “Medaillon” Annual Biennial/RHS. Royal Horticultural Society. https://www.rhs.org.uk/plants/119538/valerianella-locusta-medaillon/details
• Utah State University Extension. Lamb’s lettuce in the garden. https://extension.usu.edu/yardandgarden/research/lambs-lettuce-in-the-garden.pdf
• Valerianella locusta  – Plant Finder. https://www.missouribotanicalgarden.org/PlantFinder/PlantFinderDetails.aspx?taxonid=287435&.
• Mâche | UC Agriculture and Natural Resources. (n.d.). UC Agriculture and Natural Resources. https://ucanr.edu/site/uc-master-gardeners-santa-clara-county/mache