How to sow vegetables
The method of sowing depends on which vegetables you want to grow. Some vegetables, carrots and parsnips for example, are sown outdoors, directly in their final positions. Still others, leeks for example, are grown outdoors and later planted to their final positions. Others are sown under cover or indoors for planting out in spring or for potting on and growing under glass. This be can be rewarding if you want to enjoy earlier crops or grow vegetables that need that extra protection.
It is easiest to sow vegetable seeds in spring, summer and autumn into prepared beds where they will eventually be cropped. This is known as direct sowing.
This is a good way to sow seed economically, since less thinning will be needed after the seeds germinate.
- Sow two or three seeds every few centimentres or where one final plant is intended. The easiest way to do this is by marking out a grid pattern and sowing the seed at the ‘stations’ where the rows cross
- Once the seeds have come up, choose the healthiest and ‘thin out’ the others
Whether you are sowing in traditional rows or using the station sowing technique, it is important to thin seedlings so that the plants do not compete with each other for water, nutrients and light. See individual vegetable profiles for thinning distances.
- When seedlings have grown their first true leaves (that resemble those of the adult plant, not seed leaves), pinch off the tops of the weakest seedlings at ground level or, better still, remove entire seedlings
- The ideal spacings for each vegetable vary, but will be indicated on the seed packet
Sowing in containers
- Seed trays are suitable for starting off vegetables that will be moved on (known as ‘pricking out’) to their own containers or outside
- Seeds can also be sown in 7.5cm (3in) pots, recycled fruit or vegetable punnets or any other container with drainage holes in the bottom
- Modules or cell trays are a very efficient way of raising seedlings, allowing you to transplant, causing minimal damage to delicate roots
- For larger seeds such as broad beans, use deeper, individual containers such as cardboard tubes
- For ‘cut and come again’ crops where the plants will remain, use containers 10-15cm (4-6in) deep – polystyrene or plastic fish crates with drainage holes are ideal
Sowing tender crops in greenhouses and tunnels
- Courgettes, pumpkins, squash, tomatoes, sweetcorn and cucumber are examples of vegetables sown in spring or early summer in a greenhouse or polytunnel for transplanting outside
- Remember to harden off vegetable plants before setting in their positions if they are to go outside
- Crops such as aubergines prefer to be under cover all season, as do glasshouse tomatoes, melons and cucumbers. These can be grown in borders, growbags or containers
- For growing techniques for specific vegetables, please see our Grow Your Own web pages
Sowing crops under cover to extend the season
The growing season can be extended by making use of the warmer, protected environment inside greenhouses and tunnels, and to a lesser extent coldframes, cloches and fleece.
- Start early and finish late with sowings of chard, Chinese greens, coriander, lettuce, parsley and radish
- These can be sown directly into glasshouse borders or into containers without extra heat. Broad beans such as ‘The Sutton’ and ‘Aquadulce Claudia’ can be sown from November to January for cropping in late May-June
Shop-bought seed composts will give more reliable germination than homemade composts. They will also be low in nutrients that are unnecessary for germinating seeds and be free of pests and diseases.
Try to use fresh compost each year, as it deteriorates if stored. It’s best to use up any old compost along with fresh, in baskets or containers for more mature plants, rather than seedlings.