Seed Sowing 

Simple steps to Successful

Seed Sowing in the Spring!


When can I sow indoors?


Many vegetables like Tomatoes, Broad Beans and Runner beans can be sown in late February and early March indoors before being planted out in May or June once the risk of frost has passed.


Annuals such as Marigolds, Sweet peas and Sunflowers also benefit from starting off indoors to create a wonderful show of colour in the summer.


After sowing your seeds, label, lightly water again and place clear polythene or a sheet of glass over the top or place in a heated propagator and keep around 18C unless the instructions state otherwise.

Sowing the Seeds


Different sizes of seed are usually sown in different types of trays or pots.


Small seed is normally thinly scattered over seed compost in a shallow seed tray and pricked out later for transplanting. Mixing small seed with some dry sand helps to ensure an even distribution.


Slightly larger seeds can be sown into modular trays or plug trays either in individual cells or 3cm (1") apart if in trays. This helps reduce any shock to the plant and the roots when the time comes to pot them on.


Large seeds such as Sweet Peas, Broad Beans and Courgettes benefit from growing individually in 9cm (3") pots. A tip for larger seeds, to give them a head start, is to lay them on a saucer or plate with a little bit of water. This starts them shooting a little faster along with making sure you only plant viable seeds and not having to replant any that failed to germinate.


Certain seeds need slightly different growing conditions such as light exclusion or scarification

(scratching or nicking the seed coat).  Always follow the instructions on the packets.



Small and slightly larger seed require a seed compost.  Seed composts have been specially milled so that they are fine and light and have less nutrients which can harm young plants.


Larger seeds can be grown in either a seed compost or multi-purpose composts.


Keep the compost just moist at all times to ensure consistent growing conditions until the seedlings are ready to be pricked out or transplanted.

Growing On


Check the seeds daily for signs of germination. Once germinated, covers and lids should be removed to allow for better ventilation.


When the seedlings have two true leaves (not the first seed leaves produced after germination) they will be ready for pricking out / transplanting into larger pots around 9cm in diameter.  Use a dibber or blunt stick to gently loosen the compost around the roots, hold one true leaf between your thumb and finger and gently lift from the tray keeping as much of the compost around the roots as possible and place into a hole made in the new container.  Plant up to the first seed leaves but no deeper. Gently firm the compost and water in.

Seeds that have been grown in modular or plug trays can wait a little longer, until the roots have filled the module or plug fully, before potting on into 9cm pots or straight into tubs and baskets.


Once the weather is warm enough and the chance of frost has passed, the seedling can be slowly hardened off before final potting in beds, tubs or the vegetable plot.