When you buy seeds in the UK they will have a ‘use by’ date on the packet. Often they will be in a sealed foil packet within the main packet. This excludes air and light which keeps the seed fresh and viable so long as they’re neither roasted nor frozen.
Monarda Bee Balm Seed Head
The information in this article and especially the chart showing how long seeds keep for is just as useful for those saving their own seeds as those buying seeds
Unfortunately many seeds are supplied in quantities way beyond that required for the average garden or allotment for one year.
It is curious that seeds I purchased in France have use-by dates some 10 years ahead whereas those purchased in the UK have 2 or 3 years on the packet at most. I have asked some seed merchants for comment and will update if they ever do!
Seed Storage
| Seed | Life in Years | Avg Days to Germination |
|---|---|---|
| Bean, Broad | 2 | 21 |
| Bean, French | 2 | 14 |
| Bean, Runner | 2 | 14 |
| Beet | 5 | 13 |
| Beet Spinach | 5 | 13 |
| Broccoli | 5 | 8 |
| Cabbage | 5 | 8 |
| Carrot | 3 | 16 |
| Cauliflower | 5 | 8 |
| Cucumber | 7 | 9 |
| Kale | 4 | 8 |
| Kohlrabi | 4 | 7 |
| Leek | 3 | 14 |
| Lettuce | 4 | 7 |
| Marrow | 6 | 7 |
| Courgette | 6 | 7 |
| Onion | 4 | 14 |
| Parsley | 2 | 10 |
| Parsnip | 1 | 17 |
| Peas | 2 | 10 |
| Radish | 4 | 6 |
| Salsify | 2 | 12 |
| Spinach | 2 | 11 |
| Swede | 2 | 8 |
| Sweetcorn | 3 | 9 |
| Tomato | 3 | 7 |
| Turnip | 2 | 8 |
So what to do with that half packet of seeds you have left over?
The four main points are to keep the seeds dry, cool, but not frozen which would damage them as the ice crystals would disrupt the cells, dark and to exclude air.
Reseal the little silver foil packets by folding over and then place the seeds in an airtight tin or plastic storage box. Ideally you would keep them in the fridge but anywhere cool will have to suffice in most households.
Seed Lifespan or Longevity
How long your seeds will last when the packet is opened will vary according to the seed, storage conditions and how near the end of its life the seed was when packed. The table How Long Seeds Keep For is a guide, subject to the caveats above.
Checking Seed Germination Rate
If you have a left over packet of seeds that you are unsure of, perhaps it’s been kept in poor conditions or results weren’t what you expected then you can check the germination rate for your seeds. See article below:
Seed Germination & Viability Testing
Seed Saving Articles, Information & Resources
- Freezing and Cold Storing Seeds for Long Term Storage
- Saving Your Own Seeds – General Guide to Seed Saving
- Seed Saving to Improve Biodiversity
- Seed Storage & Longevity Lifespan – How Long Seeds Will Keep For
- Seed Germination & Viability Testing
- Seed Saving: Storing Seeds: Seed Viability
- What Are F1 Plants & Seeds: How & Why of F1 Hybrids
- Seed Saving Heirloom or Heritage Seeds
- Seed Saving: Carrots | Save Your Own Carrot Seed
- Seed Saving: Peas | Save Your Own Pea Seed
- Seed Saving: Tomatoes | Save Your Own Tomato Seed
