How to grow from seed: Part 1
Want to grow your own but don’t know where to start? The task of growing from seed can seem daunting if you’ve never done it before. Now is the perfect time of year to begin getting your hands into the soil, but if you haven’t got naturally green fingers and find your plants die for no apparent reason, this blog will help you turn your patch into a source of satisfaction instead of stress. The Soil Association’s head of horticulture, expert gardener Ben Raskin, gave us some tips.
1) Soil is the key, so start with the compost
Get hold of some good quality seed compost and sieve it well if it’s lumpy, especially if you’re planting small seeds. This isn’t the time to be using your own homemade compost – it will probably be too high in nutrients which when they dissolve inhibit germination. Once it’s in the containers, the texture should be firm but not packed. Gently smooth the top of the compost but don’t press it down.
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2) Find appropriate containers
Module trays are great, as you can plant out delicate seedlings without disturbing the roots. Plants which quickly develop deep root systems will prefer bigger pots. Seed trays work well for sowing lines of seed that will be thinned out (e.g. salads). Old takeaway cartons with holes punched in the bottom for drainage make excellent seed trays and you can put the lid underneath to catch any drips, or on top to keep the compost moist. The cardboard insides of loo rolls make a biodegradable container which you can then plant directly into the ground later. They will add organic matter to your soil and be beneficial in the long run!
3) Check the condition of your seeds
Old seed, or seed that has got damp, won’t germinate as well as fresher seed that has been stored properly. Ideally, seed should be kept in an airtight container in a dry, dark place. Even if your seed is good, always sow more seed than you want as not every seed will germinate.
4) Plant the seeds at the right depth
Generally, that’s about as deep as the seed is big, so chunky beans need to be deeper than delicate carrot seeds. For very fine seed, place them on top of the compost and gently sprinkle some more compost over the top until they’re just covered. Poke small holes in the compost to drop slightly bigger seeds in and cover them with compost.
5) Label your seeds
It’s important to know what’s planted where and when so that you can make sure it’s given the best conditions for germination. Some seeds need warmer soil or more water before they will sprout. You can make your own labels from lolly sticks, or write on the non-shiny kind of plastic pots with a pencil.
6) Make sure they’re kept moist, but not too wet!
Test the soil with your finger, making sure to wiggle it under the surface slightly to check moisture levels there. If it feels a bit dry, water gently with a fine rose until it feels just damp.
7) Keep the seeds warm until they germinate
Most seeds like a temperature of between 15-20 °C to sprout. Covering the trays or pots with a sheet of glass or clear plastic will create a mini greenhouse and keep them cosy until they’ve got started. Some people also like to use heated propagators to make sure conditions are perfect, which can give good results.
8) Once the tiny seedlings begin to show, give them plenty of light
When they get big enough to handle they should be planted either into bigger containers or outdoors. Always handle them by the leaves, not the stems, as they are easily bruised. A plant can survive losing a leaf but if the stem is damaged it will die.
Jess Gotham began volunteering with the Soil Association in March. Before that, she worked on sustainable housing with Transition Homes Totnes, and spent time WWOOFing.