Seed viability lookup

What this lookup does

Seed packets rarely carry a true expiry date, but different crops keep for very different lengths of time. This table gives the typical storage life for common vegetables so you can decide what to keep, what to sow first, and what to replace. It is a reference, not a verdict — a figure past its "typical" life often still grows, just more thinly.

How to read it

• Short-lived crops (parsnip, onion, sweetcorn) are worth buying fresh each season rather than storing.
• Long-lived crops (tomato, cucumber, radish) are worth saving and keeping.
• Treat the numbers as ranges. They assume cool, dry storage — a warm kitchen shortens them, a sealed jar in a cool room extends them.

What actually shortens a seed's life

Two factors dominate: heat and moisture. Warm, damp conditions age seed quickly; cool, dry, steady conditions keep it viable far longer than the table suggests. Storage in a sealed jar with a sachet of silica gel, kept somewhere cool and dark, is the simple version of what seed banks do at scale.

What to do with old seed

Do not bin seed on age alone. Run a quick test first — see how to test old seeds or use the germination rate calculator — and if the rate is low, sow thicker using the seeds-to-sow tool. For the longer explanation behind this table, read how long seeds last.

Limitations

• Figures vary by source depending on how "storage life" is defined and how seed was kept.
• Variety and seed lot matter. Freshly harvested, well-dried seed outlasts a cheap packet that sat in a warm shop.
• It is a guide, not a guarantee — test your own seed for a real answer.

Frequently asked questions