Before You Start
Germination is the most critical —and most commonly botched —phase of any grow. Seeds that fail to germinate often died from avoidable mistakes: too much water, too little warmth, or impatient handling. Understanding a few fundamentals before you open that breeder pack will save you money and frustration.
What you'll need (for most methods)
- Filtered or distilled water (tap water can work, let it sit 24h to dechlorinate)
- pH meter or drops —target pH 6.0–.0 for water
- Tweezers with soft tips (to handle seeds without touching them)
- A warm location (seedling heat mat recommended but not required)
- Paper towels, plates, or your chosen germination medium
Avoid touching seeds with bare hands —skin oils can contaminate the shell and interfere with germination. Use clean tweezers or rubber gloves.
Paper Towel Method
The paper towel method is the most popular approach for good reason: it's simple, gives you full visibility on taproot development, and works reliably. You'll see exactly when a seed has cracked and when the taproot is ready for transplant —no guessing.
Step-by-Step
- •Full visibility on germination progress
- •Very high success rates
- •Free —no equipment needed
- •Easy to control moisture
- •Risk of taproot tearing during transplant
- •Requires careful moisture monitoring
- •Can mold if too wet
Direct to Soil
Planting directly into moist soil eliminates transplant shock entirely —the taproot grows into its final medium from day one. This is how nature does it. The downside: you can't see what's happening and you can't tell if a seed is germinating or dead until the seedling breaks the surface.
Step-by-Step
Best for: Experienced growers who want to avoid transplant shock. Not recommended for first-timers who want visibility into the process.
Water Glass Soak
Soaking seeds in water is best used as a preparatory step before the paper towel method, not as a standalone germination technique. The soak softens the seed shell and can speed up germination —especially useful for older seeds or those with very hard shells.
Step-by-Step
Jiffy Pellets / Peat Pods
Jiffy pellets are small compressed peat discs that expand in water. They provide an excellent germination environment and can be transplanted directly into soil without disturbing the root zone —the mesh outer layer breaks down naturally. A popular choice for growers who want more control than paper towel but less hassle than setting up a custom medium.
Step-by-Step
Note: Jiffy pellets are slightly acidic (pH ~6.0), which suits cannabis seedlings well. Available at most garden centers or online for about $10–5 per pack of 50.
Rapid Rooters / Rockwool
Rapid Rooters (by General Hydroponics) and Rockwool cubes are the preferred germination medium for hydroponic setups. They provide an ideal air-to-water ratio in an inert medium, making them excellent for both seed germination and clone rooting. More advanced, but very reliable for experienced growers.
Rapid Rooters —Steps
1. Pre-soak Rapid Rooters in pH 5.5–.0 water for 30 minutes.
2. Insert seed into the pre-made hole with the pointed tip down. Pinch the hole slightly closed to keep the seed secure and in the dark.
3. Place in a propagation tray with a humidity dome. Keep at 75–0° with bottom heat from a heat mat. Seedlings typically emerge in 3– days.
4. Once seedling is established (3– days post-emergence), transplant the entire plug into your hydro system, net pot, or soil —no disturbance to roots.
Rockwool: Must be pH adjusted to 5.5–.0 before use. Soak in pH-buffered water overnight. Rockwool's default pH is too high for cannabis seedlings. Flush thoroughly before seeding.
Troubleshooting
Most common causes: too cool (below 65°), too dry, or old seeds. Check temperature first —it's the #1 culprit. Add a heat mat if you don't have one. Re-moisten the paper towel if it's gotten dry. Give it 2– more days.
Try gentle scarification: lightly rub the seed between sheets of fine-grit sandpaper to thin the shell slightly. This can help water penetrate and trigger germination in stubborn seeds. After scarifying, try the water glass soak for 12h, then back to paper towel.
Too much moisture or not enough airflow. The towel should be damp, not saturated. Swap out the moldy towels immediately for fresh damp ones. Add a few drops of 3% hydrogen peroxide to your water next time to prevent mold.
This happens when a seed is planted incorrectly or shifts position in the medium. The plant will self-correct —gravity and phototropism will eventually orient the seedling correctly. Don't dig it up. Be patient.
Caused by planting too shallow or low humidity during emergence. Wait 12–4 hours and let the plant try to shed it naturally. If it's still stuck after 24h, use a spray bottle to moisten the shell, then use tweezers to gently pry it off. Be very careful —cotyledons tear easily.
The seed is likely a dud. Quality seed banks from reputable breeders have very low dud rates —less than 5%. If multiple seeds from the same pack fail, contact your seed bank. ILGM's 100% guarantee and NASC's store credit policy both cover this scenario.
Transplanting the Taproot
This step trips up many first-timers. The taproot is delicate —a broken taproot often means a dead or severely stunted plant. Handle with care.
Timing: Transplant when the taproot is 0.5–cm (¼u2013½inch) long. Waiting until it's longer increases the risk of it getting tangled in the paper towel fibers.
Tools: Use tweezers or a toothpick to handle the seed —never pinch the taproot itself. Hold the seed by its outer shell.
Placement: Create a small hole in your medium about 0.5cm deep. Place the seed in with the taproot pointing downward. Gently cover with loose medium —don't pack it.
After transplant: Mist the surface lightly and add a humidity dome if possible. The seedling should emerge in 12–2 hours. Begin gentle lighting (CFL or LED on dim) once it breaks the surface.
Germination Guarantees —What They Cover
If seeds genuinely fail despite correct technique, a germination guarantee covers you. Here's how the major banks compare:
| Seed Bank | Guarantee | Requirements |
|---|---|---|
| ILGM | 100% | Photos of dead seeds + approved method |
| Herbies | 70% minimum | Photo proof of failed seeds |
| Homegrown Cannabis Co | Yes | Photo documentation required |
| NASC | Store credit | Contact customer service |
| Seed Supreme | None stated | Case-by-case |
Note: Guarantee terms can change. Verify current policy with each bank before purchase.
FAQ
How long does it take cannabis seeds to germinate?
What is the ideal germination temperature?
Should I use tap water or filtered water?
Can I germinate seeds directly under a grow light?
Which germination method has the highest success rate?
Ready to Find Your Seeds?
Now that you know how to germinate properly, make sure you're starting with quality genetics. Compare the top seed banks side-by-side.