How to Tell If Your Cannabis Seeds Are Still Good
You just found a stash of cannabis seeds from that grow you planned… two years ago. The big question is: are they still good? Or are you about to waste time on seeds that won’t even sprout?
This guide shows you how to:
- Identify good vs bad seeds by sight and feel
- Run a quick float test at home
- Store seeds properly for long-term viability
- Know when to toss and when to plant
TL;DR – Quick Signs Your Seeds Are Still Viable
| Sign | Good Seeds | Bad Seeds |
|---|---|---|
| Color | Dark brown, gray, striped | Pale green, white, faded |
| Shell | Hard, smooth, slightly glossy | Cracked, dry, brittle, soft |
| Weight | Dense, solid in hand | Feels light or hollow |
| Float Test | Sinks after 60 min in water | Floats = likely dead |
| Age | <2 years with good storage | >3 years or stored poorly |
What Do Good Cannabis Seeds Look Like?
Healthy cannabis seeds usually:
- Have a dark color with natural patterns like tiger stripes or marbling
- Feel firm and smooth to the touch
- Are slightly glossy—not dusty, dry, or cracked
Avoid planting seeds that are:
- Pale green, white, or completely faded
- Visibly cracked or feel empty
- Dry and brittle, like old wood
For a more detailed breakdown of seed health and troubleshooting, check out our Cannabis Germination Guide.
The Float Test: Quick Way to Check Viability
Here’s a simple test you can do at home:
How to float test your seeds:
- Fill a glass with room-temperature water
- Drop your seeds in
- Wait 60 minutes
- Observe results
- Seeds that sink: Likely viable
- Seeds that float: Often dried out or hollow
Important: Only do this if you’re planning to germinate them within 24 hours. Extended soaking can trigger rot or premature germination.
How Long Do Cannabis Seeds Stay Good?
Under ideal conditions, cannabis seeds can remain viable for up to 5 years—but only with proper storage.
Safe shelf life guidelines:
- 1–2 years: Excellent germination potential
- 3+ years: Possible but lower success rate
- 5+ years: Rarely viable without professional preservation
If your seeds don’t sprout even after trying ideal methods, read our article on Why Your Cannabis Seeds Aren’t Germinating (And How to Fix It Fast).
Best Storage Methods to Keep Your Seeds Alive
Seed viability depends heavily on how they’ve been stored. Here’s what works:
Ideal cannabis seed storage conditions:
- Cool: 41–46°F (5–8°C)
- Dark: No light exposure
- Dry: Relative humidity <9%
- Sealed: Use airtight containers like jars or vacuum-sealed bags
- Consistent: No temperature swings
Avoid freezers unless you’re using seed bank-grade cryo-storage. For long-term tips, check out our full Cannabis Seed Storage Guide.
What to Do With Questionable Seeds
- Test them: Use the paper towel method for germination testing
- Practice with them: Even if they’re weak, they can be used for training or experiments
- Don’t mix them with your premium genetics—label everything!
Want Fresh Seeds You Can Count On?
All Hypno Seeds genetics are:
- Lab-tested for germination rate
- Recently harvested and vacuum-packed
- Stored under professional-grade conditions
Whether you’re growing autoflower, photoperiod, or high-THC feminized strains—we’ve got the freshness guarantee.
👉 Browse All Strains
Final Thoughts: Don’t Plant What Won’t Grow
Old or badly stored seeds can waste your time, energy, and soil. Use these tips to test your stash, improve storage, and know when it’s time to upgrade.
If your seeds are past their prime, give your next grow the best start possible—with fresh, premium cannabis seeds from Hypno Seeds.
