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Growing from Seed
Forget all those stories about seeds being hard to grow. Seeds are programmed to grow. The skills for growing seeds successfully are easily learned and equipment required need not be expensive.

Sowing seeds is often thought of as a thing of the past. Punnets of pansies, lettuce and tomatoes are available easily and cheaply in the garden centres, why bother to sow your own?

Well, quite apart from the satisfaction of watching seedling germinate and grow, sowing seeds saves money and makes a wider range of varieties available to the home gardener.

Many heritage plants are only available as seed and it enables you to propagate more of your favourite perennials, annuals, vegetables and woody plants.

Seed sowing is an all year activity, although spring is a time when we are busy planting both vegetables and flower seeds. In the colder months you can grow seeds indoors under cover ready for transplanting into the garden or for growing in tunnels or the greenhouse.

Sowing under cover
Sowing seeds into trays or pots for later transplanting into the garden extends your garden season by getting you off to an early start. You can grow plants that that need extra warmth to germinate or a long growing season.

Tender vegetables (e.g. lettuce) should be sown under cover in trays or pots so that they can be transplanted into the vegetable garden once the weather warms and the risk of frost is past. Runner beans and courgettes, marrows, cucumbers, tomatoes, lettuce, celery and leeks are amongst the many plants that you can start early under glass in this way. Petunias, snapdragons, cosmos and many other flowers can be sown indoors and transplanted into the garden.

Choosing Containers
Always use clean containers when planting. Last year's seed trays and pots can be washed, to avoid the risk of disease, and reused.

You can plant into seed trays or into individual pots. Some seeds, such as lettuce, are best sown in a seed tray, and then 'pricked out' after they have produced true leaves (not the first leaves) into seed trays, tubes or cells.

Other seeds, such as courgettes and beans, are best panted into an individual pot from the beginning, with the obvious benefit of less root disturbance on transplanting into the garden.

Alternatively, you can use plugs, planting cells or a similar, proprietary product from your local plant nursery. This is 'cell-planting' where a seed 'tray' is divided up into small cells, which minimise root disturbance when planting out.

You can make your own 'cells' with from milk cartons, cardboard strips or by rolling newspaper around a can or jar and flattening the bottom. Place in a seed tray and handle sparingly as these can be rather fragile. Newspaper cylinders can be planted intact but remove cardboard strips or milk cartons before planting, leaving the seedlings separated and easy to plant with minimal disturbance.

Seed Raising Soils
The soil mix you use is a matter of trial and error, and personal preference. Seeds need to be able to push new roots out into the soil to gain the nutrients and moisture they need. Seed starting soils ideally should be friable, absorb moisture but let excess moisture drain away, and not compact. Sterile soil reduces the risk of disease, and mixes with fresh compost and organic matter may not be suitable for this reason.

There are many commercial mixes available for starting seeds, or a regular potting compost may be suitable. Homemade mixes can be very successful.

Sowing Seeds
Fill a container with seed mix and moisten (it should feel like a wrung-out dishcloth). Plastic pots and seed trays can benefit from a single layer of newspaper to prevent soil leaking, then fill your seed containers to the top of the lip and tamp the soil gently with the bottom of an identical pot. Toy blocks are often a perfect match for cell packs.

Sow seeds evenly in seed trays to encourage good growth. Crowded seeds will be leggy and compete for nutrients. Small seeds (lettuce and petunias) need to be planted less than a centimetre apart, medium seeds (tomatoes and marigolds) a centimetre apart and large seeds (peas) at least 2.5 centimetres apart.

In individual pots plant seeds towards the centre of each pot or cell. Plant two seeds per pot. This method is ideal for courgettes, marrow and plants with large seeds that need real warmth to germinate.

Cover the seeds according to the instructions - some seeds germinate better without light, others prefer it. The rough rule is to cover seeds to three times their diameter. Label the container, as it is very easy to muddle seedlings when juggling multiple sowings!

Where to grow undercover
A glasshouse, greenhouse, conservatory or bright (but not scorching) windowsill is ideal for starting seeds. Make sure that you turn the seedlings regularly to encourage even growth and prevent leggy seedlings.

Water gently and regularly to maintain moist but not wet soil. Lack of air circulation and over watering can lead to damping off, when the seeds collapse and die.

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Growing from Seed
Growing from Seed

Growing Seeds - Things You Need

Seeds Available from most garden centres. Check sowing times, seed viability dates and days to harvest for vege
Spade, garden rake and a line for outdoor sowing
Seed raising mix, pots or trays, and trowel or scoop for growing indoors
Dibber or pencil for pricking out and transplanting seedlings

Most of these can be obtained inexpensively, e.g. seed can be saved from year to year, and recycled materials are perfectly suitable

Seeds - Programmed to grow
Seeds - Programmed to grow

Seed Growing Containers
Plastic pot Inexpensive, reusable and easily found in a wide range of sizes. Take care not to over water and the walls do not let water escape. Not recyclable once broken.
Clay pot Expensive and easily broken, the porous walls help good drainage, reusable but harder to clean than plastic.
Plastic cell pack Inexpensive and easy to clean, range of sizes available and good for larger sowings. Small size means that strong growing plants may soon need larger containers. Not usually strong enough to be re-used and not biodegradable
Peat cell pack and pots Naturally sterile, transplanting shock is reduced as each cell can be planted with the seeding and the roots grow through, but relatively expensive and can collapse if over-watered. Check it is from a renewable resource
Newspaper cells, milk cartons and cardboard 'cell' packs all recycle common household materials, newspaper cylinders can be planted with the seedling, reducing transplant shock. Milk cartons must be thoroughly washed first, remove carton and cardboard 'cell' strips before planting. Watch for over watering that can cause containers to rot or collapse.
Plastic seed trays Relatively inexpensive and widely available, easy to clean and reusable. Check for good drainage holes.
Wood seed trays Expensive and rarely seen today. Not easy to clean, reusable, absorbs moisture so helps drainage

Use trays, plugs and cells

Use trays, plugs and cells

Recycled containers - milk carton and newspaper 'cells'

Recycled containers - milk carton and newspaper 'cells'

Some seeds should be sown one seed per pot

Some seeds should be sown one seed per pot

Growing undercover

Growing undercover

Starting seeds in a seed tray gets your garden underway early

Starting seeds in a seed tray gets your garden underway early
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Last revised 27 May '02