Lettuce Seeds

Why Grow Lettuce?

Lettuce Seeds for Different Growing Goals

Lettuce varieties should be selected by growth habit, leaf texture, harvest method and planting season. Head-forming lettuces need more space and time, while loose-leaf types are particularly useful for rapid and repeated harvesting.

Choose Lettuce by Type

Cos Lettuce and Romaine Lettuce

Cos and romaine are common names for the same general type of upright lettuce. In Australia, the name cos lettuce is more widely used, while North American seed catalogues and recipes commonly use the term romaine lettuce.

Loose-Leaf Lettuce or Heading Lettuce?

When to Plant Lettuce Seeds in Australia

Lettuce grows most reliably during cool to mild weather. High temperatures can reduce germination, increase bitterness and encourage plants to bolt before a useful crop is harvested.

These planting periods are general guides. Local elevation, frost, seasonal weather and variety selection can alter the most suitable sowing time.

Can Lettuce Grow in Winter?

Yes. Lettuce is commonly grown through autumn and winter in many Australian regions. Cool conditions can produce crisp, tender leaves and delay premature flowering.

Growth becomes slower during short days, severe frost or prolonged cold. Use a sunny position, maintain drainage and protect tender seedlings where necessary.

Can Lettuce Grow in Summer?

Lettuce can grow during summer, but hot soil and high daytime or nighttime temperatures can reduce germination and accelerate bolting.

Lettuce Seed Germination Requirements

How to Germinate Lettuce Seeds

1. Choose clean trays, cells or pots.
   Use containers with effective drainage, or prepare a fine outdoor seedbed.
2. Fill with seed-raising mix.
   Use a fine, free-draining medium rather than heavy or compacted soil.
3. Moisten before sowing.
   Water the growing medium gently so it is evenly damp.
4. Sow the lettuce seed shallowly.
   Scatter or place the seed on the surface and cover it with approximately 3–5 mm of fine mix.
5. Maintain cool to mild conditions.
   Protect the tray from intense heat and direct drying sun during germination.
6. Keep the surface moist.
   Use gentle watering or misting so the fine seed is not displaced.
7. Provide bright light after emergence.
   Move seedlings into strong natural light or suitable supplementary lighting.
8. Thin crowded seedlings.
   Retain the strongest plants and reduce competition before roots become extensively entangled.
9. Transplant at a manageable size.
   Move seedlings once they have several true leaves and can be handled without severe root damage.
10. Harden seedlings gradually.
    Expose plants progressively to outdoor sunlight, wind and temperature changes.

Can Lettuce Seeds Be Sown Directly?

Lettuce can be direct-sown into prepared soil or raised in trays before transplanting. Both methods can be effective when moisture, pests and spacing are managed carefully.

How to Grow Lettuce from Seed

1. Choose a cool, bright growing position.
   Use full sun during mild weather or light afternoon shade during warmer periods.
2. Prepare fertile, well-drained soil.
   Incorporate mature compost or another suitable source of organic matter before sowing or transplanting.
3. Plant during suitable weather.
   Schedule the crop so most leaf or head development occurs under cool to mild conditions.
4. Space plants by harvest stage.
   Baby-leaf crops can be grown more closely than mature loose-leaf or heading lettuces.
5. Transplant carefully.
   Avoid burying the crown and minimise root disturbance.
6. Maintain consistent moisture.
   Regular watering supports tender leaves and reduces plant stress.
7. Apply light mulch where appropriate.
   Mulch can conserve moisture and reduce soil temperature around established plants.
8. Feed moderately.
   Use a suitable vegetable fertiliser to support steady leaf growth without excessive soft growth.
9. Protect young plants.
   Monitor for snails, slugs, aphids, caterpillars and chewing pests.
10. Harvest at the required stage.
    Pick baby leaves, remove mature outer leaves or cut complete heads while they remain fresh and firm.

How Far Apart Should Lettuce Be Planted?

Lettuce spacing depends on the mature size of the variety and whether the crop is intended for baby leaves, repeated loose-leaf picking or complete heads.

Follow the product-specific directions where a variety requires different spacing.

Growing Lettuce in Pots

Does Lettuce Need Full Sun?

Lettuce generally grows well in full sun during cool weather. Approximately four to six hours of direct sunlight can support strong leaf development.

During warm conditions, morning sun with light afternoon shade may reduce heat stress and premature bolting. Deep shade can produce weak, elongated plants.

How Long Does Lettuce Take to Grow?

Growing time varies with variety, temperature, spacing and the stage at which the crop is harvested.

These periods are general guides rather than guaranteed maturity dates. Check individual product pages for variety-specific information.

How to Harvest Lettuce

Lettuce can be harvested as baby leaves, mature outer leaves or complete plants. The best method depends on the variety and intended use.

When Should Lettuce Be Picked?

Harvest lettuce while the leaves are crisp, fresh and appropriate for their intended use. Do not wait for plants to become excessively large, bitter or elongated.

• Pick leaves before a tall flower stem begins developing
• Harvest during the cooler part of the day where possible
• Select leaves without significant pest or disease damage
• Use clean hands, scissors or a knife
• Avoid crushing tender leaves during handling
• Cool harvested lettuce promptly

Does Lettuce Grow Back After Cutting?

Loose-leaf lettuce can continue growing when individual outer leaves are removed and the central growing point remains intact. This is commonly described as cut-and-come-again harvesting.

Baby-leaf crops cut above their growing points may produce a second flush, although the regrowth can be less uniform than the first harvest. Complete heads cut below the crown generally provide little useful regrowth.

Why Does Lettuce Bolt?

Bolting occurs when lettuce shifts from leaf production to flowering and develops an elongated central stem. It is a natural stage of plant maturity but reduces the quality of a leaf crop.

Why Does Lettuce Taste Bitter?

Lettuce can develop a stronger or bitter flavour when plants are exposed to heat, drought, maturity or the beginning of flowering.

• Grow the main crop during cool to mild conditions
• Maintain consistent moisture
• Harvest leaves while young and tender
• Pick during the cooler part of the day
• Remove plants once they begin producing flower stems
• Use varieties suited to the expected season

Common Lettuce Growing Problems

Can Lettuce Be Grown Indoors?

Lettuce can be grown indoors where plants receive sufficient light, suitable temperatures, airflow and root space. Loose-leaf and baby-leaf varieties are generally easier to manage indoors than full-sized heading lettuces.

Companion Planting with Lettuce

Lettuce can share garden space with crops that have compatible seasonal and moisture requirements. Its relatively compact root system and short growing period make it useful between slower-maturing vegetables.

Mixed Lettuce and Mesclun Seed

Mixed lettuce seed combines several lettuce varieties, while mesclun may contain lettuce together with other salad greens. The exact composition should be checked on the individual product page.

Packet and Bulk Lettuce Seeds

Important Considerations for Commercial Growers

Commercial lettuce production requires careful variety selection, seasonal planning and harvest scheduling. Germination, plant uniformity, head specification, crop density, field losses and market requirements all influence production efficiency.

Frequently Asked Questions