Seed Germ
Cannabis Seed Germination Guide
Germination is the crucial first step in your cannabis growing journey. This guide covers the most reliable methods to sprout your seeds and ensure a strong start for your plants.
Understanding Germination
Germination is the process where a seed awakens from dormancy and begins to sprout. For successful germination, cannabis seeds need:
- Moisture: To soften the seed shell and trigger growth hormones
- Warmth: Ideally 22-25°C (71-77°F)
- Darkness: Initially, before the sprout emerges
- Gentle environment: To protect the delicate taproot
A healthy cannabis seed is typically dark brown with tiger stripes, feels hard, and is roughly the size of a peppercorn. Fresh, quality seeds have germination rates of 90%+ when proper techniques are used.
What to Expect
Seed absorbs water and swells
Taproot emerges from seed shell
Taproot grows downward and seed moves upward
Cotyledons (first leaves) emerge and open
Germination Methods
There are several reliable methods to germinate cannabis seeds. We recommend the paper towel method for beginners, but all these approaches can work well:
Paper Towel Method
The paper towel method is reliable, allows you to monitor progress, and makes transplanting easy once the taproot appears.
What You'll Need:
- Cannabis seeds
- Paper towels (unscented, non-dyed)
- Two plates or a container with lid
- Distilled or filtered water
- Tweezers (optional)
- Spray bottle (optional)
Step-by-Step Instructions:
Prepare Your Materials
Dampen 2-4 sheets of paper towel with water. They should be wet but not soaking or dripping.
Position Seeds
Place seeds on one half of the paper towel, spacing them about 2-3cm apart. Fold the other half over to cover the seeds.
Create Humidity Dome
Place the folded paper towel between two plates, creating a "humidity dome." Alternatively, use a container with a lid.
Store in Warm Location
Place in a warm location (22-25°C/71-77°F). Top of refrigerator or near (not on) a heating source works well.
Check Daily
Check seeds daily to ensure paper towels stay moist. If they begin to dry, spray with water. Look for the emergence of the white taproot.
Ready for Planting
Once taproots reach 1-2cm (typically 2-5 days), they're ready for planting. Handle seeds carefully, preferably with tweezers, avoiding touching the fragile taproot.
Tips for Success:
- Don't let paper towels dry out completely
- Keep temperature consistent
- Handle germinated seeds with extreme care
- Plant seeds with taproot pointing down
- Don't wait too long after taproot appears (1-2cm is ideal)
Planting Your Germinated Seeds
Once your seeds have germinated and developed a taproot, it's time to plant them in their growing medium.
Soil Planting Steps:
- Prepare container: Fill pot with pre-moistened soil mix
- Make a small hole: Create a 0.5-1cm deep hole with your finger or a pencil
- Plant the seed: Carefully place the seed with taproot pointing down
- Cover lightly: Gently cover with a thin layer of soil
- Mist the surface: Lightly water the planted area
- Maintain environment: Keep soil moist and warm (22-25°C/71-77°F)
Planting Depth Guide
The ideal planting depth is about twice the width of the seed, typically around 0.5-1cm (¼-½ inch). Planting too deep can prevent emergence, while too shallow might expose the seed.
Caring for Cannabis Seedlings
The seedling stage is delicate but crucial for developing strong, healthy plants. Here's how to care for your newly sprouted cannabis:
Light
First 24-48 hours: Seedlings don't need intense light immediately. Gentle, indirect light is sufficient.
After emergence: Place under grow light or in a sunny window. For indoor grows, keep LED lights 50-60cm away initially.
Light schedule: 18-24 hours of light per day for both autoflowers and photoperiods at this stage.
Watering
Frequency: Keep soil consistently moist but not waterlogged. Water when the surface looks dry.
Method: Water around the seedling, not directly on it. Use a spray bottle or small watering can with a narrow spout.
Water quality: Use pH-balanced water (6.0-6.5 for soil). Avoid chlorinated tap water if possible.
Environment
Temperature: Maintain 22-25°C (71-77°F) during the day, slightly cooler at night.
Humidity: Keep relative humidity around 65-70% for optimal growth.
Air circulation: Provide gentle air movement, but avoid direct drafts on seedlings.
Nutrients
First two weeks: No additional nutrients needed. Seedlings use stored energy from the seed.
After two weeks: Begin with very light nutrient solution (¼ strength) if using commercial potting soil.
Signs of need: Slight yellowing of first leaves may indicate it's time to start light feeding.
Common Seedling Problems & Solutions
Damping Off
Symptoms: Stem becomes thin and weak at soil level, seedling collapses
Causes: Overwatering, poor drainage, fungal infection
Solution: Improve air circulation, avoid overwatering, ensure clean environment
Stretching
Symptoms: Tall, lanky seedling with large gaps between nodes
Causes: Insufficient light intensity or distance
Solution: Move light closer or increase intensity; support stretched seedlings with toothpicks if needed
Seed Shell Stuck
Symptoms: Seed casing remains stuck on cotyledons, restricting growth
Causes: Low humidity, seed shell too dry
Solution: Carefully mist with water to soften shell; if persistent, very carefully help remove with tweezers
Curling Leaves
Symptoms: Seedling leaves curling down or up
Causes: Heat stress, light intensity, improper watering
Solution: Adjust environmental factors; ensure proper distance from lights
Transplanting Seedlings
For autoflowering cannabis, we recommend germinating directly in the final container (15-20L) to avoid transplant shock. However, for photoperiod strains, you may start in smaller containers and transplant later.
When to Transplant:
- When seedlings have developed 3-4 sets of true leaves
- When roots are visible at drainage holes
- When growth slows due to becoming root-bound
Transplanting Steps:
- Prepare larger container with pre-moistened soil
- Water the seedling's current container 2-3 hours before transplanting
- Make a hole in the new container's soil slightly larger than the current root ball
- Carefully remove seedling by supporting the stem and squeezing the sides of the container
- Place into new container at the same soil level as before
- Gently firm soil around the seedling and water lightly
- Keep out of intense light for 24-48 hours to reduce stress