As the gardening season gets underway, many enthusiasts are wondering whether to plant seeds that are past their 'sow by' date. Experts say it is often worth taking a chance on older seeds, though success rates vary.
YouTuber and grow-your-own expert Huw Richards, who has over 750,000 subscribers, believes seed packets are just guidelines. 'A seed either wants to grow or it doesn't,' he said, comparing seeds to supermarket products where best-before dates are not always a strict cut-off. Some vegetable seeds, such as cucumbers, tomatoes, pumpkins and radishes, can remain viable for over five years, while onions, spinach and parsley tend to last only one or two years.
Matthew Appleby, editor of Horticulture Week, has had success with out-of-date seeds, including pumpkins and courgettes. 'It’s a bit more hit and miss,' he said, but recommended having a go. To improve chances, experts suggest double sowing—placing four or five seeds in a pot to see if any germinate. A germination test, placing seeds between damp paper towels, can also indicate viability before planting.
Storage is key to extending seed life. Huw Richards advises storing opened packets in an old ice cream tub or cardboard box in a cool, dry cupboard. Adding desiccants like rice can absorb moisture, and airtight glass jars are ideal. Appleby notes that resealable packets are best, but a simple peg or tape works; seeds should be kept cool, dark and dry.
While germination rates decline with age, Appleby stressed that success also depends on the gardener's skill—using the right temperature, potting medium and water. So, rather than discarding old seeds, it may be worth giving them a chance.
