Seed Sowing
Photos by Eva Nemeth
I am itching to start sowing seeds, and with the weather warming up this week I will be making a tentative start – nothing outdoors yet of course, just in seed trays or pots. I’m lucky enough to have a greenhouse, but it’s not heated so I often start things off on a windowsill or table indoors, and then move the seedlings out into the greenhouse as soon as they have germinated.
What to sow now
You can sow hardy annuals now, which will be ready to plant out in April or May, but it’s better to wait for another month or so before sowing half hardy annuals like cosmos or zinnias, as they will need to stay indoors for longer, before being planted out in late May or June. February is also a good time to sow perennials, and there are plenty that are both easy and quick to flower from seed, including echinaceas, agastache and Verbena bonariensis. I’m sowing marigolds, poppies, phlox and Chinese forget-me-nots this week, as well as two or three perennials: Lysimachia ephemerum, Calamintha nepeta and Baptisia australis. You can also start sowing a few veg seeds (hardier types such as broad beans, beetroot and chard) if you want to start them off in modules first.
Calendula Touch of Red Buff Photos by Sabina Rüber
Phlox Blushing Bride
Papaver Amazing Grey
How to sow
A lot of seed sowing is trial and error and what works for one person sometimes doesn’t work for another – or what works one year is a disaster the next. There are so many variables to tip the applecart – weather, seed and compost quality, water – and reliable germination and growth can never been guaranteed. I’ve been doing this a long time and still have plenty of failures. You just have to learn to move on and not get disheartened; you’ll find your own favoured methods and will gradually improve your success rate.
Sowing ‘under cover’ is the term used for sowing in seed trays or pots indoors, whether inside your house, garage, shed or greenhouse, and in mid-February all plants need heat to germinate and some initial protection from the cold. That’s not to say you should rush off and buy a fancy heated propagator. They can be very useful, but I have never used one and make do with shelves above radiators, the back of the Aga, or just a sunny windowsill if the seeds need heat to germinate. It’s important to note though: as soon as you see those first shoots coming through, move the seed tray to a cooler place, otherwise the seedlings will grow too quickly and become weak and spindly.
Photos Eva Nemeth
Pots or trays
I sow my flower seeds in modular trays or 12-14cm round pots – larger seeds in individual modules, and smaller seeds in the pots. I have a stack of plastic seed trays that have lasted for years, and in the past have used plastic cell inserts, which always work well. I’m trying not to buy any more plastic trays though, so have started experimenting with wooden seed trays and fibre inserts. They are cheap and good but they wick the water away much quicker than the plastic cell trays, so you literally can’t miss a day of watering.
For larger seeds, fill the modules with seed compost, gently flattening it with a pot tamper, and then water the compost before sowing. (Beware packing the compost too tight otherwise air will be pushed out and the seedlings will dwindle). Sow two seeds to a module, by pushing them gently into the compost and covering with a layer of finely sieved compost if necessary. For smaller seeds, sow them as finely as possible on the surface of the compost (too many will mean too much competition for space, so they won’t thrive). Depending on the individual instructions on the seed packet, either cover them with a fine layer of sieved compost or vermiculite, or leave them on the surface, gently pressing them down. Cover the tray or pot with a plastic bag or plastic propagator lid that will keep everything moist, and leave the seeds in a warm place to germinate. Watch your seeds like a hawk and be excited about seeing them grow!
For more plant info, see The Flower Garden blog, or buy my book!
