Wednesday 20 February 2013

Seed sowing for winter

Even though we are still in summer, it is well and truly time to prepare for winter in the garden. I've been thinking about what I would like to be harvesting in the next six months and deciding what I need to propagate now.


Little seedlings growing



With preparation and planning winter can still be a productive time in the garden. This will be my first winter in Malmsbury, so it will be interesting to find out what will grow through the frosts and waterlogged soils my neighbours have been warning me about.


Winter is the time for harvesting brassicas, alliums, root crops, leafy greens and salad greens. Brassicas being from the plant family Brassicaceae, including brussels sprouts, broccoli, cauliflower, cabbage, kale, rocket, asian greens and khol rabi. Alliums include onions, leeks and chives. Some other vegetables I've been propagating are chard, spinach, lettuce, radicchio, endive, fennel, turnips, carrots, beetroot, celeriac, coriander, parsley and spring onion.


A lot of people seem to feel that seed sowing is difficult or mysterious, but you don't really need a green thumb or good luck for it succeed. You just need good potting mix, good seeds and consistency. A bit of practice definitely helps too, but don't let this put you off starting!


Now is a good time of year to raise seedlings, as it is still very warm so you don't need to have a greenhouse or cold frame. You do need a spot where your seeds receive some protection from the sun and you need to water them once or twice every day. I have my seedlings growing on a table that receives about three hours of sun in the morning and again in the late afternoon, I water them every morning and on hot or windy days in the afternoon as well.


I always use a good quality potting mix rather than seed raising mix. Seed raising mix has no nutrients, which means seeds will germinate well but soon become stunted unless you feed them regularly with liquid fertiliser. You can buy or make your own organic liquid fertiliser, but I always prefer the simplest solution, in this case potting mix. The most important aspect of potting mix is the texture. It needs to have a reasonable component of sand and largish (about 3mm) chunks/particles of bark to stop the potting mix from compacting which inhibits seed germination. If you have no idea what to buy choose a relatively premium brand, preferably certified organic.

Two and a half weeks later
The key to success is keeping the seeds and later, seedlings, constantly moist. When I first sow the seeds, I always cover them with potting mix (even a little sprinkling for tiny seeds like celery) and firm the potting mix down a little to ensure the seeds are completely surounded by potting mix and there are no air bubbles. I water them in immediately, and always keep them well watered and moist. It only takes one instance of the potting mix drying out to kill seeds, especially small ones. 

Seedlings will start to emerge within one or two weeks depending on the type of seed. I find that rocket is always the first to come up. Once the seeds germinate, the seedlings are more prone to drying out so will need closer attention.

Most seedlings of annual vegetables are ready to plant out after 3 or 4 weeks at this time of the year.

Seeds germinating after 10 days
Broccoli seedlings

Leek seedlings emerging

Silverbeet seedlings

Dill Seedlings