Chris Collins on… seed sowing

In his latest blog, our head of organic horticulture Chris Collins brushes off his propagator and pots as he prepares for the sowing season
Alternative text should describe the visual content of the image.
Chris relishes the seed sowing season – pictured here in our greenhouses at Ryton

March is the beginning of the busy period for all of us that like to raise and grow our own plants. It’s a month when my professional and private life fuses together - and I literally eat and sleep horticulture!

I’m currently getting organised by cleaning my propagators and pots and stocking up on peat-free compost, making sure I’ve got enough labels, and dusting off my all-important tamper and sieve.

I like to sow my seeds in three waves, beginning with tender plants like aubergine, chillies, and peppers. These tend to be slow-growing plants, so I like to get them off to an early start. It’s way too early to be thinking about putting any of these plants outside, so my baby plants will be carefully raised on a warm windowsill, then a polytunnel (covered with fleece for extra pre-protection if a frosty night comes along) until late May.

Chris's seed-sowing tips

I sow my seeds in small trays where the compost is gently tamped (firmed), the seeds sown, and further compost sieved over the top and tamped again. This ensures the seed is sitting in good, fine compost that will offer little resistance to the radical and plumule as they emerge from the seed case. The tamping also makes sure that the seed is touching the compost evenly and creates the right conditions for maximum germination. These are simple but highly effective methods.

I’ll place my freshly sown seeds into a heated propagator, and I expect them to be poking out their heads in a week or so. If you’re keeping plants or newly germinated seedlings on a windowsill, it’s important to remember to turn them as often as possible. A window only lets light in from one angle and your seedlings will stretch toward this light, unturned seedlings or young plants will elongate and become stretched and leggy. It may seem like a lot of faff, but it does make a difference.

I must turn hundreds of seedlings four or five times a day, but this period is incredibly important to my relationship with my plants. In short, it’s a bonding exercise and I’m investing my time for a return of delicious organic food and bountiful floral colour later in the season. A further little tip for you is to stroke your seedlings once they have been turned, as this mimics the wind and helps the plants become stronger and stockier.

Outdoor sowing begins

March is also a busy time for drill sowing on my allotment. I’ll sow salad and root crops into ground that has been lightly forked, raked, and firmed to create the perfect seed bed. I’ll use a garden line and a dibber to create the drill, the depth of which is determined by the seed size (a rule of thumb is two thirds the size of the seed). Then the seeds are sown at stations at the desired spacing. For smaller seeds, I sow thickly then remove excess seedlings as they grow, and these sacrificed seedlings go straight into a salad.

Once sown, I’ll sieve compost over the top, gently tamped, and write a label. Sowing in lines like this means I can identify the chosen plants from the wild ones that will also begin germinating as the soil warms.

Seed sowing timings

Obviously, March is still a cold month and it could easily snow, so the way I judge if the soil is warming is to look at the grass in my local park. These plants will start to put on growth after a few sunny days. When the soil temperature reaches five degrees and stays like that for a week, I’m happy to drill sow - but always with the fleece at hand should a cold snap come along.

My first wave of seed sowing happens in March, but waves two and three will take place later in the spring - and so the gardener’s busy season has begun.

If you enjoy reading this blog and would like to get more advice on a successful growing season, I will be hosting a series of talks and workshops this spring and summer. I’d love to see you! Click the links below to find out more. In the meantime, happy gardening!

29th March: How to Garden Organically in a Small Space

In this online talk Chris will show you how to turn a tiny garden into a flourishing oasis, using his tried-and-tested techniques.

5th April: Learn how to Grow a Perfect Potager

In this one-day hands-on workshop, Chris will show you how to plan your own potager (the French word for 'kitchen garden'), which combines edible plants with flowers.

31st May: Organic Gardeners’ Question Time

Join Chris and a panel of horticultural experts for the first of three online gardening clinics.