Iceberg lettuce 'Great Lakes 118'

1000 Seeds

Iceberg Lettuce ‘Great Lakes 118’ is a classic crisphead lettuce that produces large, dense heads with crisp, pale-green leaves. It is a cool-season crop and is particularly suitable for salads, sandwiches and fresh dishes. Iceberg types form firm hearts when they receive suitable temperatures, moisture and growing space.

Lettuce generally grows best in full sun with fertile, moisture-retentive but well-drained soil. Hot, dry conditions can cause lettuce to bolt prematurely, resulting in bitter leaves and poorly formed heads.

🌱 Best Planting Time

• Gulf region: September–April
• Kuwait: October–February
• Best period in Kuwait: October–December
• In warmer Gulf areas, autumn through early spring is generally the most suitable period.
• Avoid sowing during the peak summer heat.
• For a continuous harvest, make small successive sowings every 2–3 weeks while temperatures remain suitable.

🌿 How to Plant the Seeds

1. Use a fine, fertile and well-draining seed-starting mix.
2. Moisten the soil before sowing.
3. Sow the seeds very shallowly, approximately 0.3–0.6 cm deep.
4. Cover lightly with fine soil or compost.
5. Keep the growing medium evenly moist.
6. Place the seed tray in a bright, well-ventilated location.
7. Once seedlings have several true leaves, thin or transplant them carefully.
8. Avoid overcrowding, as crisphead lettuce needs adequate space to form a firm head.

🌡️ Germination

• Suitable temperature: approximately 15–20°C
• Germination: commonly around 7–14 days
• High temperatures can reduce or delay lettuce germination.
• During warm Gulf weather, germinate the seeds indoors or in a shaded, temperature-controlled location.
• Keep the seed-starting mix moist but not saturated.

🌱 Transplanting

Transplant when seedlings are strong enough to handle and have several true leaves.

• Plant spacing: approximately 25–30 cm
• Row spacing: approximately 30 cm
• Choose the coolest suitable location available during warmer months.
• Water immediately after transplanting.
• Harden seedlings gradually before exposing them to stronger outdoor conditions.

Crisphead/hearting lettuces need more space than loose-leaf types so they can develop good heads.

☀️ Sunlight

• Full sun is preferred during the cooler Gulf season.
• Aim for approximately 4–6+ hours of good sunlight.
• In the Gulf, morning sun is particularly useful.
• During warmer weather, provide light afternoon shade to reduce heat stress and help delay bolting.
• Avoid extremely hot reflected heat from walls, concrete and paving.

💧 Watering

Lettuce has shallow roots and needs consistent moisture.

• Keep the soil evenly moist.
• Water whenever the surface begins to dry.
• Morning watering is preferable.
• Increase watering during warm, dry weather.
• Avoid allowing plants to wilt repeatedly.
• Avoid waterlogged soil.
• Mulching can help retain moisture and keep the root zone cooler.

🌱 Soil

Use fertile, loose and moisture-retentive soil with good drainage.

• Add mature compost or well-rotted organic matter before planting.
• A fertile loam or sandy-loam soil is suitable.
• Avoid soil that dries out extremely quickly.
• Avoid heavy, poorly drained soil.
• Lettuce generally performs best in soil close to neutral pH.

🌿 Fertilizing

• Add mature compost before sowing or transplanting.
• Use a mild balanced vegetable fertilizer if the soil is not sufficiently fertile.
• Avoid excessive nitrogen.
• Consistent moderate nutrition encourages healthy leaf growth and good head formation.

🥬 Head Formation & Harvest

‘Great Lakes 118’ is grown primarily for its crisp, tightly formed head.

Harvest when the head has become firm and well developed, but before the plant begins to bolt. Cut the entire head close to the soil surface with a clean knife.

Hot, dry conditions can cause premature bolting, making the leaves more bitter and preventing proper head formation.

🪴 Growing in Containers

Iceberg lettuce can be grown successfully in containers.

• Use a container at least 25–30 cm wide and deep.
• Plant one large head per suitably sized container or allow adequate spacing for multiple plants.
• Use fertile potting mix with compost and good drainage.
• Containers are especially useful in the Gulf because they can be moved into light afternoon shade.
• Avoid dark containers placed directly on extremely hot surfaces.

Lettuce is well suited to container cultivation when moisture is maintained consistently.

🐛 Common Pests & Problems

Watch for:

• Aphids
• Slugs and snails
• Cutworms
• Birds feeding on young plants
• Lettuce root aphid

Possible diseases include grey mould and downy mildew, particularly where humidity is high and airflow is poor.

🔥 Gulf Climate Tips

• Treat ‘Great Lakes 118’ as a cool-season crop in the Gulf.
• In Kuwait, October–December is a particularly useful period for establishing the crop.
• Start seeds in a cooler, protected location if outdoor temperatures are still high.
• Provide afternoon shade as temperatures rise.
• Keep the soil consistently moist to reduce heat stress and bolting.
• Avoid sowing during the hottest summer months.
• Successive sowing every 2–3 weeks can provide a more continuous harvest during the suitable season.
• Good airflow is important, especially in humid coastal Gulf areas.
• Harvest heads promptly once they become firm.

🌱 Growing Tip: For the best results in the Gulf, sow ‘Great Lakes 118’ during the cooler season and keep the plants consistently moist. Morning sun, light afternoon shade and avoiding extreme heat will help the lettuce develop firm, crisp heads instead of bolting.