English 
Seed is living material, so it ages. Storing seeds looks simple, yet most germination is lost in a drawer nobody thinks about. A handful of straightforward rules keeps seed usable for years instead of months.
What happens inside a seed in storage
A seed holds a small dormant plant plus a store of energy. That store depletes slowly, even while the seed appears to do nothing at all.
Heat and moisture accelerate the process sharply. Cold, dry storage slows it down, which stretches the reserve much further.
The three factors that matter
Temperature, humidity and light decide nearly everything between them. Of the three, moisture is the most dangerous, because it also makes mould possible.
Light does the least damage, although darkness still helps. A sealed opaque box solves that point immediately.
The fridge as the default answer
For most growers a refrigerator is the best location. It sits around four degrees and barely fluctuates.
Keep the seed in an airtight container inside it, though. Fridge air carries more moisture than people expect.
Why you let the container warm up
Taking a cold container from the fridge and opening it straight away causes condensation on the seeds. That moisture does exactly what you were avoiding.
Let the container reach room temperature for half an hour first. Only then open it, take what you need and close it again.
Freezing: only with dry seed
Freezing can preserve seed for a very long time, but only when moisture content is low enough. Any water inside forms ice crystals that damage cells.
For home use freezing is therefore rarely necessary. A fridge delivers almost the same result at normal quantities, without the risk.
Packaging that works
An airtight glass or rigid plastic container performs best. Paper envelopes breathe and admit moisture, which becomes a problem over time.
Feel free to put the original pack inside the container. That keeps the line and batch information attached to the seed.
Using a desiccant without overdoing it
A small silica gel sachet keeps the air inside the jar dry. Too much desiccant, however, can dry the seed itself, which also causes harm.
One small sachet per jar is enough. Replace it once it changes colour or looks visibly saturated.
Labelling is not optional
After two years nobody remembers which seed came from where. Write the line, the supplier and the purchase date on every pack.
Add the tested percentage when you know it. A line such as Jack Herer feminized is sold by several suppliers, so that distinction becomes useful later.
How long seed stays good
Well-stored seed usually remains usable for three to five years. After that it often still germinates, although it takes longer and the percentage drops.
Badly stored seed can decline noticeably within a single year. That difference comes almost entirely from temperature and moisture.
Testing periodically
If you keep seed longer than two years, test it occasionally. Ten seeds between damp paper give a clear picture within a week.
Note the result alongside the pack. You then know whether to allow extra seed when planning a run.
Why ripeness at harvest still counts
Seed harvested unripe starts with a smaller reserve and therefore ages faster. Good storage slows that disadvantage without removing it.
Colour tells you something: ripe seed is dark, hard and lightly striped. Pale or soft seed usually belongs to an early harvest.
Shipping matters too
Seed that spends days in a warm van or a metal mailbox loses a little before it ever reaches you. You have limited influence there, beyond choosing the supplier.
Put a new order away properly straight away, therefore. The first days at home are often exactly the days when the pack sits on a kitchen counter.
A simple system that works
Use one box in the fridge holding small jars, one per line. Write a short list on the box covering what is inside and when you last tested it.
That way the jars themselves get opened far less often. Every time a jar stays closed, the seed inside gains time.
Moving house or being away
A removal box in a hot car ranks among the worst places for seed. Carry the jar with you instead and get it cool again quickly.
Being away for a while needs no action at all. Seed in a sealed jar in the fridge requires no maintenance.
Small habits with large consequences
A few routines cost more germination than they should:
- Keeping seed on a shelf above the grow space, where it stays warm.
- Opening the jar daily just to look.
- Leaving seed in a car compartment or a loft cupboard.
- Handling seed with damp hands.
None of these destroys seed instantly. Together, though, they take years off it.
Handling a larger stock
When you buy a lot at once, split it across small containers. Every time a jar opens, fresh air reaches the seed inside.
Keep one jar as the working jar and leave the rest sealed. A line you run often, such as Purple Punch feminized, then stays available in small portions.
After opening a pack
An opened pack can go straight back into the container. What matters is closing it and keeping moisture out.
Seed you have already soaked cannot be stored again. That has to be sown within a day, whatever the line.
Dry, dark and cold in that order
Of the three factors, dry matters most. A damp seed in the fridge spoils faster than a dry seed at room temperature. Therefore secure dryness first, darkness second and cold last. Consequently you avoid the classic mistake of putting everything in the fridge inside a paper envelope.
Desiccant: how much and how
One small silica sachet inside the jar is enough, provided a piece of paper separates it from the seed. By contrast, direct contact pulls too much moisture from one side. Therefore fix the sachet to the lid. In addition, silica saturates over time and needs replacing.
Condensation on opening
When you take a jar out of the cold, leave it sealed until it reaches room temperature. Consequently airborne moisture never settles on the seed. In fact this is the step most people skip, and it is the one that ruins entire lots.
Keeping part of every pack back
Never sow a whole pack in one run. A heatwave or a failed pump can wipe out the lot and teach you nothing about the genetics. Therefore keep three or four seeds sealed in the fridge as a second chance.
Labelling for the long term
Write the variety, the source and the date on the jar itself rather than on tape. Therefore two similar jars stay distinguishable years later, which is exactly how long properly stored seed remains viable.
Freezer or fridge
A freezer works well for long term storage, yet it demands discipline. The enemy is not the cold but the condensation when you open the container. Therefore keep the bulk of your collection frozen and untouched, and keep a small working jar in the fridge for regular use. Consequently the main store never goes through repeated temperature cycles, and each cycle is exactly what shortens the life of a lot.
Checking an old collection
Before planning a season around seed you have kept for years, germinate three from each jar as a check. Consequently you learn which lots are still strong and which need replacing. Therefore the surprise arrives in a cup on the counter rather than in the middle of a grow.
Frequently asked questions
Can a fridge freeze seed by accident?
No. An ordinary fridge stays above zero and makes an excellent storage place.
Does seed need darkness?
It helps, although light matters less than heat or moisture. A closed box handles it automatically.
How do I recognise old seed?
Hardly at all from the outside. A small germination test gives far more certainty than looking or feeling.
Does feminized seed keep for less time?
No. Shelf life depends on ripeness and storage rather than seed type. A classic like Skywalker Kush feminized behaves no differently from regular seed.
