So with a handy supply of pots, modules, trays, cardboard tubes and perhaps a paper pot maker along with slightly longer - maybe even warmer - days you are ready to sow some seeds. You will need some good seed compost. From a bag it can feel rough and gritty – this means that it will drain well and keep the structure nice and open for seedling roots to push through. You can make your own from your compost heap; it will need sieving to break it up and mixing with horticultural grit to get the right structure. Moist compost can be very cold so we put ours in the sunshine to take the chill off before we use it.
Fill up your pots loosely and then tap them to settle the compost – please don’t be tempted to pack is as much compost as you can as this will hinder the roots of your seedlings and it won’t drain well. Then use your finger tips to make holes or dents to pop the seeds in. The size of each seed acts as its own guide to sowing depth – the basic rule is to cover seeds with roughly their own depth of compost. Here is the rough guide we use
Barely cover: baby leaf, celery
Sow at about ½cm: broccoli, carrots, cauliflower, kohl rabi, lettuce, marigolds, okra, tomatoes, chillies & peppers, purslane, swede & turnip
½ to 1cm deep: aubergine, brussel sprouts, cabbage, chicory & endive, corn salad, cucumbers, leek, melon, onion, radishes, sweet peas, leaf beet
Between 1-2cm: courgettes, collards, kale, French beans, spinach, spring onions, sunflowers, sweetcorn
Deeper at 2-3cm: beetroot, broad beans, nasturtiums, peas, pumpkins & squashes (small seeded varieties between 1&2cm deep), runner beans.
Depth is important because planting too deep could mean they run out of energy before reaching the surface and too shallow can risk them drying out. The good news is that seeds want to grow and will do their best but they will do better with the right help. Starting seeds in pots gives you the ability to give them some tlc, keep them sheltered whilst they get going and moist (not wet and soggy). Once your seedling are growing well (generally when they have 1 or 2 pairs of proper leaves. you can get them ready for planting them out by hardening them off.
There is more information on each seed packet to help you along on your growing journey.