When and how to transplant cannabis seedlings

Transplanting cannabis seedlings is a crucial stage in the cultivation process. When done properly, it encourages strong root development and paves the way for healthy, high-yielding plants. This guide provides a clear and practical approach to timing and technique, ensuring your seedlings thrive in their new environment.

Why transplanting matters

Starting seeds in smaller containers—such as starter plugs or small pots—offers better moisture and nutrient control during early growth. However, as the plants develop, their roots need more space. Transplanting at the right time supports:

Enhanced root development: Prevents roots from becoming bound and restricted
Improved nutrient absorption: Larger root systems can access more resources
Healthier growth overall: Reduces stress and encourages vigorous development

When to transplant cannabis seedlings

Timing is everything. Transplant too early, and you risk damaging the young roots. Wait too long, and you may stunt growth or cause stress.

Signs that your seedlings are ready

Three to four true leaves: Once seedlings grow beyond the initial cotyledons
Visible root development: Roots emerging from drainage holes or circling the base
Plant height: Generally between 10 and 15 cm indicates readiness

How to transplant cannabis seedlings

Materials required

New containers (between 4 and 20 litres, depending on final plant size)
High-quality potting mix suitable for cannabis
Watering can with pH-balanced water
Optional: Mycorrhizal fungi to stimulate root health

Step-by-step transplanting process

1. Prepare the new container
Fill the pot with soil, leaving a space in the centre large enough for the seedling’s root ball. Moisten the soil lightly to help it settle.

2. Remove the seedling
Water the seedling’s original container so the soil holds together. Tap the sides gently and invert the container, holding the seedling at the base to ease out the root ball.

3. Inspect the roots
Look for healthy white roots. If they are circling the bottom, gently loosen them to promote outward growth.

4. Transplant into new container
Place the seedling into the centre of the new pot, at the same depth as before. Fill around it with potting mix and press gently to remove air pockets.

5. Water thoroughly
Water well to help the soil settle and reduce transplant shock.

Post-transplant care

Lighting: Use moderate light immediately after transplanting; avoid intense exposure for 24–48 hours
Humidity: Keep humidity levels moderate to reduce stress
Observation: Look for signs of stress like wilting or slowed growth and adjust care accordingly

Tips for successful transplanting

Avoid overwatering: Ensure containers have proper drainage
Use high-quality soil: A well-aerated mix with nutrients will support healthy root development
Minimise transplants: Especially for autoflowers, which are sensitive to repeated repotting

By following these practices, your cannabis seedlings will adapt quickly to their new containers, giving them the best chance at a strong, healthy grow.

For premium-quality seeds and more cultivation advice, visit Mavericks Genetics.