Germinating Old Marijuana Seeds

Sprouting old marijuana seeds is difficult, but not impossible. Here’s how to do it and, in the process, save yourself some seed-buying money. Just found some seeds at the bottom of a random drawer? Here are some tips to help you germinate old cannabis seeds. We can only expect to use the old seeds with the cost of seeds floating above potheads’ reach. However, improper or long-term storage of seeds can cause

The Good Germin’: How To Germinate Old Weed Seeds And Bring Them Back To Life

Before there were marijuana clones and mother plants, there were marijuana seeds, the foundation of the cannabis industry. And here’s some big news for you: The price of quality marijuana seeds is going up while availability is going down.

If you were waiting to buy seeds of the famous, scintillating heritage or landrace marijuana strains we’ve been featuring, now’s the time. I’ve been tracking seed prices of quality strains sold by reliable cannabis seed resellers, and I’ve found that in the past year, prices have gone up an average of 30 percent.

Now, let’s talk about the challenge of germinating old, stale, or otherwise defective marijuana seeds.

No matter if you get your marijuana seeds from seeded buds (sometimes called bag seed), from seed resellers, from friends, or from dispensaries, seeds from different strains can show substantial variation in size and minor variation in shape. What you should be concerned about are seeds that don’t look like the seeds in the main photo accompanying this article.

Properly bred, dark-colored and patterned marijuana seeds like the ones in the above photo are seeds that by far possess the highest germination rate and produce plants with the most vitality and performance.

But if your cannabis seeds are pale, green, gray, shrunken, split, dried out, misshapen, poorly marked, or possess a hazy sheen (kind of like old wax that dried on a car before it could be buffed out), then those are defective cannabis seeds. Take a look at the below photo, which shows defective cannabis seeds that are far less likely to germinate.

Green, split seeds and seeds that aren’t properly shaped (mature cannabis seeds should look like miniature footballs) are immature seeds that didn’t fully ripen before the buds they were forming in were harvested. These seeds are a waste of your time.

Seed defects develop if your seeds have been stored improperly, or if the seeds are more than 4–5 years old. Also, if you get cannabis seeds from the less-reputable resellers, you might receive old or otherwise defective seeds. I’ve seen growers who eagerly awaited their seed order, only to be disappointed when they tore into seed packs to discover easily identifiable duds.

In many cases, the disreputable seed seller won’t refund the order or send a replacement order, and the would-be grower is left with a mixture of acceptable-looking seeds and defective ones.

Seeds that are grayish and sheeny are old seeds, and likely desiccated. Old seeds sometimes split or crack. If seeds of any shape are pale, light brown, gray, split, or cracked, they’re defective. But you may be able to salvage some of them so they grow out into plants that yield buds.

Tried And Tested Methods For Getting Old Seeds To Germinate. But Do These Methods Work?

Growers offer many tactics for germinating old seeds, and I’ve tried all their suggestions. I want to emphasize from the outset, if cannabis seeds are grossly immature, they’re unlikely to ever germinate, and it’s not worth trying to. For that reason, the following germination suggestions are for seeds that were allowed to mature and ripen fully before they were harvested.

Method 1: One of the most generic suggestions for germinating old, stale seeds is to soak them in reverse osmosis water pH adjusted to 6.1 for 24–48 hours, before placing the seeds into a rockwool cube, rapid rooter, peat pot or other germination media.

Result: I’ve seen no benefit from this suggestion.

Method 2: This one is rather extreme and time consuming. It involves scraping off the outer layer of the seed, sometimes including the shell itself, exposing the embryo and cotyledon, which are usually white, gray-white or greenish-white.

You then place the unshelled seed material into your regular germination media. Obviously, this is a severe tactic, and you shouldn’t expect it to work. But if the alternative is to not germinate the seeds at all, it’s worth a try anyway. If it doesn’t work, you’ve lost nothing. If it works, you’re a winner.

Result: It worked for me about 15 percent of the time I tried it on old seeds.

Method 3: Another radical tactic is to manually split one side of the seed shell, narrowly exposing the embryo and other internal material that is usually protected by the hard outer shell. The split seed is immediately placed in the usual germination media.

Result: My success rate for this tactic has also been about 15 percent.

Method 4: Over the years, I’ve seen companies offer “old seed soak kits” that allegedly contain special materials that stimulate old seeds to germinate. I contacted those companies and asked for third-party test data and ingredients information so I could ascertain if its products have any validity. Strange that the customer service reps refuse to provide information beyond vague, meaningless verbiage such as, “Our product contains bio-catalysts.”

They also refused to provide product samples. I have to tell you, if a hydroponics manufacturer or seeds producer isn’t confident enough in their products to provide samples for testing, this is an indication that their products are no good.

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Result: Grower friends of mine bought several brands of “old seed soak” products and found them to be no more efficacious than soaking old seeds in pH-balanced reverse osmosis water, or just putting unsoaked old seeds into germination media.

If “seed soaker” products contain anything useful at all, it would likely be gibberellic acid, which has been used to treat marijuana seeds to induce germination, vitality and female gender.

Method 5: I’ve done experiments with stale, old seeds using a gibberellic acid pre-soak (i.e., adding gibberellic acid to get the soak solution to 100–150 parts per million), pH adjusted to 6.1, versus reverse osmosis water at pH 6.1.

Result: I had a marginally better germination rate from the gibberellic-treated seeds.

There are other experiments you can conduct if you have old seeds and you want to see if there’s any hope for them. Experiment with using seedling heat mats at a slightly higher temperature than for fresh marijuana seeds. Another tactic is to place the seeds less deep in germination media than you normally would, at about 1/4 inch (normal depth is about 1/2 inch).

You can try placing a T5 high-output fluorescent lamp over them even before they germinate, as if the light can coax them back from the dead like Jesus did with Lazarus.

Of all these methods, one thing’s for sure: Always use proper germination techniques, materials and procedures, regardless of the condition of your marijuana seeds.

Old Colombian Gold: After Germination, More Challenges

If old, stale seeds germinate at all, it usually happens several days after fresh seeds germinate. Expect fresh seeds to sprout 1–5 days after you start trying to generate them. But I’ve seen old, stale seeds that germinated after 13 days.

Even if you manage to coax defective seeds to germinate, you still have some challenges. Here’s an example of what I mean…

I had rare seeds given to me back in 2011. They were allegedly pure Colombian Gold genetics sourced from a lid of partially seeded buds in the early 1980s. Proper storage for cannabis seeds is in an airtight container in the non-freezer part of a refrigerator, and that’s where these had been since they were sourced.

The person who gave me the seeds said the last time he’d grown them was 2003. He had a 50 percent germination rate, but the strain was too difficult to grow outdoors where he lived due to climate conditions and because his locale’s high latitude is the wrong growing condition for a tropical sativa like Colombian Gold. After that failure, he put the remaining seeds back in the refrigerator and forgot about them.

I didn’t expect much from those old seeds. They were so tiny, about the size of a pinhead, and were pale gray, with that sad, dull sheen that characterizes old or dead cannabis seeds.

Still, Colombian Gold is a valuable strain and I had an indoor grow room I could easily control to give that rare heritage strain the environment it needed in which to thrive. I soaked the seeds for 24 hours in reverse osmosis water to which I’d added a very tiny amount of the vitamin B booster B-52, which is useful whenever you have stressed plants or seeds.

I planted 17 seeds about 1/4-inch deep in rockwool cubes and kept the seedling heat mat at 80°F. After five days, I saw no germination. But at day seven, one seedling popped its head above the cube, and by day 11 I had five Colombian Gold seedlings.

Five seedlings aren’t enough for a grow op, so I started fresh seeds of other sativa strains. Those seeds germinated in three days or fewer.

I measured performance of the Colombian Gold seedlings against the seedlings grown from fresh seeds. Two of the Colombian Gold seedlings were mutants — their early set of true leaves failed to develop properly, and the next sets showed the same mutation, so I terminated them.

One thing to expect from stale, old seeds: They often show mutations. Also, expect weak growth and dullness. The three remaining Colombian Gold seedlings popped their heads above the rockwool, developed 2–4 sets of normal leaves, then stalled.

As the seedlings from other strains gained height every day and their leaves grew larger, the Colombian Gold seedlings went into suspended animation. I tried giving them varying doses of light intensity and wavelength. I kept them on the seedling heat mat. After three weeks, when seedlings from fresh seeds were nearing a foot or more in height, only one Colombian Gold seedling had grown taller, but it was still several inches behind the fresh-seed seedlings.

I ended up keeping only one Colombian Gold female. It never had the vigor, root development, bud development, stalk sturdiness or harvest weight that fresh seeds of the same strain would have yielded.

This poor little female clearly lacked vitality from its earliest days, and generally plants grown from old seeds often have to be babied along. This means giving them extra doses of vitamin B, less light intensity than the other plants in the garden, more staking and other structural supports, more carbohydrates (like Bud Candy and Microbial Munch), and more potassium silicate (like Rhino Skin) to strengthen their weak stalks.

These compromised plants lack vigor, and may take longer to mature and develop in both grow phase and bloom phase. They might have hermaphroditic tendencies, weak stalks, insufficient root development, or be especially prone to spider mites, gray mold, pythium root rot and other attackers.

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I had to baby that Colombian Gold, but she rewarded me with authentic sativa buds that were long, thin, and a beautiful golden color. The high was stellar and very 1970s-ish.

If the plant had been stronger and more vital, I would have kept it as a mother plant or waited until I had suitable male pollen before breeding her. But she was an experiment, the seed she came from had lain dormant for too long, so her adult life was feeble. I was lucky to get any nice buds from her at all.

Mind you, old and stale seeds aren’t always a dead end. I’ve had nine-year-old marijuana seeds that sprouted within seven days and grew out to be lovely, strong, heavyweight marijuana plants. And those seeds had been stored in a plastic bag inside a sock in a drawer in someone’s bedroom!

The message here is that if you have defective seeds that are immature, don’t waste time on them. But if you have old seeds, there’s little harm in trying the tactics I’ve discussed to see if you can grow out any of them. You might be able to get rare genetic treasure from old marijuana seeds, which makes it worth the effort to try to germinate them.

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Here’s How To Germinate Old Cannabis Seeds

Old cannabis seeds can be hard to germinate. Luckily, there are a few techniques that can help them sprout, even if they’ve been forgotten for some time.

Did you find some old seeds in a forgotten corner of the house? Well, you’re in luck; below we’ll share some simple tips to help you germinate old cannabis seeds.


Before you start, it’s important you remember the following:

• Seeds can take a while to germinate. While healthy, fresh seeds can germinate in just a few days, old seeds can take anywhere from 2 days to 3 weeks to sprout. So be patient.

• Some seeds won’t germinate at all. Unfortunately, old seeds sometimes just don’t sprout. So, if you try all of the tips below and wait patiently without any luck, it’s likely your seeds are just too far gone.


One of the main reasons old cannabis seeds don’t germinate is because they tend to have a very hard outer shell. Now, cannabis seeds naturally have a hard shell that helps protect them until the conditions are right for them to germinate. Over time, however, this outer shell can become so hard that it inhibits the seed from germinating altogether.

To help older seeds along, it’s a good idea to try scarring them. To do so, simply line the inside of a matchbox with some fine sandpaper, place your seeds inside, and shake the box for a minute or so. This will help make some small cuts in the seeds’ outer shells to help them absorb some moisture.

If this isn’t enough, you can try carefully (and very gently) using a sharp knife like a Stanley blade to remove the ridge running along the middle of each seed. This should expose the inside of the seed a little, helping it absorb moisture and, hopefully, giving it a better chance of germinating.


Try dropping your old seeds into a glass of sparkling water. The CO₂ in the water should help the seeds absorb more moisture, encouraging them to sprout. You can also add some fulvic acid to the water to help break down the shell of your seeds. You’ll only need about 2.5ml of acid for a glass of sparkling water (roughly 250ml).


This is a very popular way to germinate seeds. And for good reason; it’s pretty successful. Here’s how to germinate your cannabis seeds using paper towel:

1. Place 2 pieces of paper towel inside a salad plate.
2. Dampen the paper towels and place your seeds on top of it.
3. Cover the seeds with another 2 pieces of damp paper towel, then cover the salad plate with another plate, and keep it in a warm, dark cupboard.
4. Check on your seeds every 2–3 days.


Sometimes, it’s best to leave Mother Nature to work her magic on your old seeds. Try scarring your seeds a little as we showed you earlier, then let them sit in carbonated water overnight. Next, prepare a small nursery pot with some high-quality soil. Make a small hole in the middle of the pot with your finger, roughly the depth of your fingernail. Drop your seed inside the hole and cover it. Moisten the soil and keep your pot in a warm place with indirect sunlight—a windowsill works great.


If you’ve tried all our tips above and still haven’t managed to germinate your seeds, it’s likely they are beyond the point of return. To avoid having the same problem next time, here are some tips to help you store your seeds:

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• Seeds like cool, dry, and dark places.
• Quick changes in temperature and humidity are really bad for seeds. Try to keep them in a jar or other container to protect them against these environmental factors.
• Seeds don’t like light. Keep them in a dark place and avoid any unnecessary exposure.
• All of our seeds are vacuum-sealed. For the best germination rates, only open a pack of seeds when you’re ready to plant them.

How To Germinate Old Cannabis Seeds

We can only expect to use the old seeds with the cost of seeds floating above potheads’ reach. However, improper or long-term storage of seeds can cause infertility – and they cannot germinate. However, how do we let those old cannabis seeds come to life again? This guide will help us convert the relics into a sea of green sections of robust cannabis fields!

Sorting Old Cannabis Seeds

The first step in any farming process is to make sure we have the right seeds, and the same goes for weeds. When harvesting autoflowering marijuana seeds, everything is preserved, and nothing is lost. This means that all types of seeds are ripe and immature. How do we distinguish good seeds from bad ones? You are considering the following.

Sorting Seeds By Color And Shape

Whether we obtained the seeds from a seed bank, a store, or a retailer, different cannabis seed strains have different colors. Mature cannabis seeds acquire a dark coat, while immature ones are brighter and usually white. The most visible colors are brown, tan, and sometimes black. In contrast, bright yellows and whites quickly identify immature seeds.

Cannabis seeds are known for their aesthetic properties and shape. Round and symmetrical seeds are best. Larger seeds have a reasonable rate of germination compared to small seeds, which tend to be immature.

Classification Of Seeds By Hardness

Although the seeds have taken some time inside storage containers, ripe weeds seeds’ hardness is not compromised. Hard and tough seeds with a smooth shell guarantee a reasonable degree of germination. Also, pay attention to wavy and cracked seeds. They will lose time and energy and will not germinate after planting.

Ways to Germinate Old Cannabis Seeds

Below we will go through 3 popular methods used to germinate old weeds seeds. Remember that we have to do the part by trying to keep the temperature between 26 ° C – 28 ° because that is where the clones seem to season-best. You must also ensure that the seed is kept in a dark area, as light can slow down the germination process.

Method 1 – Scarification

The first method is scarification. This includes causing injury to the seeds’ outer shell to allow water and air to enter, which is essential for germination. For manual scarification, we will need a container or box lined with sandpaper or any coarse material to scar the seeds’ outer surface. Put the seeds in a container or box and shake. After a while, we will find that the roots become dull, and we can see parts of the sources inside the container. Once we scare the outer shell of the cannabis seeds, we can germinate them as usual.

Method 2 – Carbonated water

The second method involves the use of carbonated water with a pH below 7. This slightly acidic solution absorbs the outer layer of the seeds. Put the seeds in a container full of carbonated water and wait for about two hours. The solution loosens the seed coat and allows it to absorb water, which helps germinate.

Method 3 – Mixture of hydrogen peroxide

Method 3 requires that we use a mixture of hydrogen peroxide to soften the seed’s outer skin. It would be best if we were careful when mixing the peroxide solution, as we can burn the seed, and it will never germinate.

To use a mixture of hydrogen peroxide for the germination process, use 1 to 2 drops of 99% hydrogen peroxide in a glass of water. After soaking for 24 hours, the outer shell is softened enough to germinate the seeds.

In addition to chemical and mechanical scarification, we can use other DIY methods to loosen seeds. For example, we can use a small knife to scratch or open the seed coat. We can explore different approaches as long as we do not damage the seed embryo.

  • One part 3% hydrogen peroxide with six parts water.
  • One part 4.5% hydrogen peroxide with nine parts water.
  • One part 6% hydrogen peroxide with 12 parts water.
  • One part 30% hydrogen peroxide with 60 parts water.

Always Use Clean, Fresh Water

Clean and clean water contains oxygen and hydrogen molecules. These are two life-supporting elements necessary for germination. Soaking the seeds for at least 12 hours allows water to enter living cells, a process known as osmosis. Now that the internal conditions promote germination, the semen embryo expands and breaks out of the protective sheath.


Old cannabis seeds sometimes pose a challenge for germination. You can sort ripe seeds, release the hard protective layer by various methods, try new chemical germination enhancers, or use biocatalysts. Similarly, soaking the clean, soft seeds in clean water will push the embryo out of its protective blanket. After trying some of the above processes to germinate the old cannabis seeds, we can be sure to grow healthy and living plants and expect good yields.