🌱 February Sowing Guide for Polytunnels

February is one of the most valuable months for polytunnel growers. The protection a polytunnel provides allows you to start crops earlier than outdoors — but success depends on choosing the right seeds and managing temperature, light, and moisture carefully.

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🌱 Essential Garden & Allotment Products for March
March is when the gardening season really begins. Seeds are being sown daily and beds prepared.

Seed Trays & Propagation Kits
View Seed Trays

Heated Propagators & Grow Lights
See Grow Lights

Seed Compost for Healthy Seedlings
View Compost

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Recommended Products — February Gardening Essentials

Early Spring Seed Collection (February Sowing)
A pack of seeds suited for February sowing — think early onions, brassicas, tomatoes, chillies, and early flowers like pansies and primroses. Great for getting a head start on the growing season.
👉 Click here to see top options

Seed & Cutting Propagation Compost
Fine, well-draining compost formulated for seeds and cuttings. Essential for giving young roots the ideal environment to establish strongly without rotting.
👉 Click here to see top options

Seed Trays & Propagator Kit
Includes reusable seed trays, modules, and clear lids to create a controlled germination environment. Helps maintain humidity and protects young seedlings.
👉 Click here to see top options

Heat Mat & Grow Lights for Seed Starting
Provides bottom heat and supplemental light — especially helpful in February’s low light and cooler temperatures to improve germination and early growth.
👉 Click here to see top options

Plant Labels & Waterproof Marker Set
Keep track of your sowings with durable labels and a weather-proof pen — very useful when starting lots of different seeds in February.
👉 Click here to see top options


🌿 Vegetables to Sow in a Polytunnel in February

These crops perform reliably under polytunnel conditions.

🧅 Onions (from seed)

  • Sow in trays or modules
  • Ideal temperature: 10–15°C

Why sow now:
Long growing season — early sowing produces stronger plants and larger bulbs.


🥬 Leeks

  • Sow thinly in trays or modules
  • Keep cool but frost-free

Why sow now:
February sowings lead to thicker stems and improved yields.


🥦 Brassicas (early varieties)

Includes:

  • Cabbage
  • Cauliflower
  • Calabrese
  • Brussels sprouts

How to sow:

  • Sow in modules

Why sow now:
Produces sturdy young plants ready for planting out in early spring.


🌿 Celery

  • Surface sow (do not cover seed)
  • Keep warm and moist

Why sow now:
Slow-growing and needs an early start to mature fully.


🌾 Vegetables to Sow in an Unheated Polytunnel

These tolerate cooler temperatures but benefit from shelter.

🥬 Lettuce (hardy varieties)

  • Sow in trays or modules
  • Protect with fleece during cold spells

🌱 Spinach

  • Sow in modules or directly into beds
  • Keep compost just moist

🫛 Peas (early varieties)

  • Sow in guttering, pots, or modules
  • Protect from mice

🌿 Broad Beans

  • Sow in deep pots or modules
  • Can be planted out under fleece later

🌶️ Warmth-Loving Crops (Only With Extra Heat)

Only sow these if you can provide steady warmth and strong light.

  • Tomatoes (18–22°C)
  • Chillies and peppers (20–25°C)
  • Aubergines (22–25°C)

Use a heated propagator or heat mat inside the polytunnel if needed.


🌸 Flower Seeds to Sow in a Polytunnel in February

Polytunnels are excellent for early flower sowing.

  • Sweet peas
  • Antirrhinums
  • Lobelia
  • Petunias
  • Begonias (from seed)

🌿 Herbs to Sow in a Polytunnel

  • Parsley
  • Chives
  • Coriander
  • Basil (only with warmth)

❄️ February Polytunnel Sowing Tips

  • Ventilate on sunny days to prevent condensation
  • Avoid overwatering cold compost
  • Use fleece inside the tunnel during cold nights
  • Remove heat once seeds germinate
  • Prioritise light over warmth after emergence

⚠️ Seeds Best Left Until March or Later

Avoid sowing these in February:

  • Courgettes
  • Squash
  • Sweetcorn
  • Climbing beans

They grow too quickly and struggle in low light.


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