How are lettuce seedlings grown?
Lettuce growing starts with the right seedling. Crop quality is decided in those first growth stages. Whether you grow commercially or in a garden, the basics of a healthy lettuce seedling do not change. A professional process, step by step:
1. Seed choice and quality
The first and most important step is seed that fits your region and growing season.
- Type: Choose curly (Lollo Rossa / Bionda), Yedikule (Cos/romaine) or iceberg according to market demand or taste.
- Certified seed: Disease-free seed with a high germination rate is essential for professional production.
2. Growing media: peat and trays
Unlike traditional methods, professional seedling production uses trays, which are critical for root health.
- Mix: Sterile peat with perlite and vermiculite is ideal. It drains for the roots while holding moisture.
- Cell count: 300-cell trays are typically used for lettuce.
3. Sowing depth and germination
The most common sowing mistake is burying seed too deep.
- Depth: Lettuce seed is very small. About two to three times the seed diameter (around 0.5 cm) is enough.
- Light: Some lettuce varieties need light to germinate, so cover only with a very thin layer.
- Temperature: Ideal germination temperature is 10–15 °C.
4. Irrigation and feeding
Once seedlings emerge, the first watering period ends and controlled irrigation begins.
- Misting: Use fine spray nozzles so seedlings are not damaged.
- Feeding: When the first true leaves appear, a low-dose balanced N–P–K liquid feed can start.
5. Light and hardening-off
Seedlings grown under cover (greenhouse or indoors) need to be prepared for outdoor conditions.
- Light: Enough sunlight is essential so seedlings do not stretch and stay weak.
- Hardening-off: About a week before transplanting we reduce watering and gradually introduce plants to outdoor conditions.
İklim Fide note: stretching
If seedlings are thin and too tall, temperature is too high or light is too low. A healthy lettuce seedling should be compact, with a thick stem and dark green leaves.