Saving and Storing Seeds

How long can you keep seeds?

Seeds are expensive to buy and for dedicated allotmenters and gardeners it is important to keep the cost down as much as possible.

  • Try sharing the seed order with a friend or neighbour to share packets [especially brassicas where you always get more than you need] or buy in more commercial quantities eg. peas where a kilo could be no more expensive than a retail packet.
  • If you are planning to buy lots of seeds, plan in advance and order from a catalogue or on-line catalogue from one of the seed-houses [small organic growers like The Real Seed Catalogue or Nicky’s Seeds, can be much cheaper], rather than from a garden centre or retail shop. You may have to pay a little extra for postage but this is more than covered by the cost of the seeds.
  • Perhaps your Allotment Association or one close to you, has its own shop. Usually, as the seeds and equipment are bought in bulk, it will be much cheaper and savings should be passed on to members.

Seed Packet Information and Instructions

To the uninitiated the information and instructions can be fairly unintelligible and, in some cases, not sufficiently informative.

I do expect with a seed packet, to be told if the plant is annual [it will grow from seed, flower and seed with one season – the life of this plant will not extend beyond one season – eg, peas and beans, tomatoes, peppers, coriander[HA – hardy annual will grow successfully in a normal year outdoors in the UK]. [HHA – this plant is a half hardy annual – it will grow in the UK in the summer season as long as there are no frosts or other difficult unseasonal conditions].

Most of the vegetables we chose to grow in our allotments will be grown as annuals although not all are considered such as, if you wish to collect seeds from them they may actually be biennials – brassicas, carrots, parsnips, parsley, etc.

Biennial – the plants will grow from seed in one year but can survive a winter in a normal winter] to grow on in the following season to flower and run to seed – eg parsley and angelica [a favourite of a friend of mine].

Perennial – perennial plants will grow from seed [or cuttings, root cuttings, etc.] to create plants which will last for many years. The length of the life of that plant will depend on the conditions, the care given to the plant, the variety and the type.

HP – indicates a hardy perennial which should grow happily for many years in suitable conditions in the UK – fruit bushes and trees, rhubarb, horseradish, etc

HHP – indicating a half hardy perennial, will need care nurturing to ensure it survives cold winter conditions – e.g. globe artichokes.

Seed packets will usually give very basic information on when and how to sow the seeds and how to grow on. However, some of the smaller and more specialised seed houses give little or no information on their seeds packets although the necessary information should be available in their catalogues or websites [these are not usually available in shops and garden centres].

The seed suppliers will rarely tell you if the seed can keep over for another year however, they should provide the date of packing [this is not always the date of seed harvesting].

Being able to carry–over seeds can be useful. As a rough guide seeds can have a life expectancy of approximately:

1 year only

Onion – seeds 1 – 2 years, sets 1 year only, Parsnips, Potatoes [are tubors, not real seeds], parsley

2 years +

Broad beans, French Beans, Runner Beans, Peas, Salsify and Scorzonera, Sweetcorn, Coriander

3 years +

Beet – leaf, Beetroot, Leeks, Lettuce, Swede, Tomatoes, Turnips

4 years +

Aubergine, Brassicas – broccoli, Brussels sprouts, cabbage, cauliflowers, kale, Capsicum – peppers and chillies, Carrots, Celery, Curcurbits – courgettes, cucumbers, squashes, pumpkins, marrows, melons, Radish, Spinach

Although I have kept some seeds beyond their life expectancy and a reasonable percentage has germinated, it is important that even seed with a long life expectancy should be stored in cool, dry, airtight conditions, in some cases even storage in a fridge will prolong seed life but, not in a freezer. Over years, for even those seed which have a long life, the viability will reduce. I have found that seeds I have collected myself from my own plants have had a much longer life expectancy than that for bought seed.

I don’t attempt to save seeds from plants where it means they will take up valuable growing space longer than necessary but, I will collect and save seeds from plants where the seeds themselves are the vegetable I will eat – eg. peas, beans and coriander and from vegetables where the crop is actually a ‘fruit’ of the plant that we will eat and therefore contains the seeds we can save – eg. squashes and pumpkins, marrows, tomatoes, peppers and chillies. This will only really work for standard seeds – not for F1 hybrids.

Beans, squashes and pumpkins have a reputation for being quite promiscuous so will probably not grow true to the original seed. I have never actually experienced much of a problem with beans although, on a couple of occasions I have had the odd climbing bean growing from a saved ‘dwarf’ variety.

Squashes and pumpkins, especially if planted among other varieties or, in a situation like an allotment field, are less likely to grow ‘true’. However, when I’ve planted them anyway, I’ve still managed to grow perfectly acceptable and tasty pumpkins. An allotment friend has suggested that growing your own seed actually gives a vegetable which is best suited to the conditions on your plot.

If you do harvest and use your own seed it is probably a good idea to buy in fresh stock every few years. I have noticed that over several years the plants grown from the saved seeds tend to lose their vigour.