Winter is still a time to grow food
Winter in the granite belt is typified by evenings chilling down to 5C to anywhere around -12C in places often followed by blue skies and sunny short days. Working outside oftens means single shirt by 10am, although jumper is needed by 3 or 4pm. Many plants can tolerate this cold and frosts and this post is about what we have found we can grow after 6 winters here.
Firstly we use a locally produced guide sheet to determine what seeds can be planted when. This is usually referring to in the ground. For many vegetables we plant them into trays and their germination and initial growth can be increased by using some sort of protective growing environment. We use a plastic covered poly tunnel for example, but there are many other methods available. Frost cloth over outside beds helps as well.
List of vegetables to grow through the Winter:
all brassicas (cabbage, kohl rabi, cauliflower, kale, etc)
asian greens (bok choy, pak choy, wombok, tatsoi, etc)
root veges (carrot, turnip, radish, beetroot, swede)
alliums (onion, spring onion, garlic [plant by end of March]
silverbeet, lettuce, English spinach, escarole
coriander seems to like late winter germination and growth, so we planted it in mid-April this year as an experiment....
If your greenhouse is large enough, then in the middle where it is warmer, you can grow some less frost tolerant greens such as amaranth - the leaves that have dark red on them... Zucchinis are another possibility - for small fruit.
You can see self-seeding lettuce coming up amongst the wombok in the 3rd photo above.. It's always good to leave some of your favourite plants to go to seed - feeds the pollinators and volunteer veges mean less work for us!
Soil preparation notes:
brassicas like the soil slightly more alkaline, so adding sprinkles of wood ash is useful.
root veges like the soil to be acid, so they should be separate to your brassicas.
broadbeans will add nitrogen to the soil so plant them where your heavy feeders have been eg tomatoes, corn, eggplants, etc
if you plant seeds directly in the soil, use only a minimum of mulch initially as warmer soil helps with germination - keep it moist.
overseeding helps reduce weed pressure
our general soil prep for a garden area involves removing old mulch and old plants, aeration with a fork, deep watering with the forking if it is dry, addition of biology with compost and/or worm castings, addition of minerals with rock dust, bentonite (just a light sprinkle), seaweed solution, lime/dolomite and then light mulch (love grass, sugarcane, etc) if seeding or thicker mulch if transplanting seedlings.
Integrated Pest Management:
early in Winter, there are still many moths and butterflies around, so getting caterpillars on your greens is to be expected. Keep a close eye out and squash them or spray with an organic product. Use dipel [Bacillus thuringiensis (or Bt)] for caterpillars if you cannot control by hand. Their eggs can often be seen to, so squashing them is also an option. Neem oil also will work, but is toxic to bees, so only spray after dusk when the bees are no longer out.
attract beneficial predators such as wasps by letting a variety of veges go to flower and having as much diversity of other flowering plants in your garden as possible. Aim to have this diversity of flowers all year round.
over watering can promote conditions that favour slugs and snails, so again be observant! Going out at night with a torch and collecting them early on can stop an infestation from occurring. Otherwise, there are various traps you can make - do an internet search.
covering garden beds with some kind of fabric/fine net will prevent flying insects from getting to your plants.
macropods can be a problem, overcome this by covering your beds with fabric or fencing them out.