Autumn is the best time to plant your winter vegetable garden. As the weather cools and the rain starts to fall more frequently it is a pleasure to get back into the garden, remove spent summer crops and plant vegetables such as cabbage, broccoli, broad beans and peas. It is an advantage to start planting at the beginning of autumn as many winter vegetables require a long growing period.
Goodbye Summer
Pull out what remains of your summer crops once it cools down. If your tomatoes are still green, make them into pickles and chutneys or hang the whole bush, roots and all, upside down in a sheltered spot outside. The tomatoes will gradually ripen. I have a little hotspot in my garden where I continue to grow summer crops until the height of winter. The rest of my garden will be transformed.
All the old plants can go to the compost bin. It is best to avoid composting diseased plants and, if you have chooks, allow them to pick over the beds, removing weeds and any pests. Try to rotate your crops if you have the room, avoiding planting the same groups of plants in the same spot year after year. This will help prevent disease build up in the soil.
Rejuvenating Soils
Winter vegetables need a rich and nourishing soil. Replenish the soil by adding animal manures and plenty of compost and lightly rake it through. Add a layer of pea straw, lucerne or sugar cane mulch on the surface.
Position
Winter vegetables require at least four to six hours of sun a day. If you have to compromise on this then try and put the most leafy plants such as lettuce, silverbeet and coriander in the more shady part of your vegetable patch. If there is an area that simply does not get enough direct sun then try growing a green manure crop instead of letting it lie fallow.
Green Manure
Green manure crops are legumes that are grown to add nitrogen and organic matter to the soil. Sow heavily in well composted soil and allow them to grow until about knee high. Do not allow the plants to flower or produce a crop. Once they have reached your knees then they can be slashed and dug back into the soil. All the nitrogen contained in the roots and foliage will then be released into the soil. Wait a few weeks for the stalks and leaves to break down before planting.
Pest Control
The cooler weather means fewer pests but they are still about. The most destructive pest at this time of year is the Cabbage White Butterfly caterpillars, known to chomp their way through your garden overnight, leaving only stalks behind, as well as slugs and snails. With all of these pests, try manual measures to remove them, or create a physical barrier around the seedlings, rather than reaching for the chemical alternatives. Always use a low-impact pesticide or make your own. For caterpillars the best product is Dipel. This targets only caterpillars, without harming beneficial insects.
Watering
Vegetables have a high water requirement and it is important to ensure you have good soil, high in organic matter and moisture retentive, as the basis of your watering system. Do not allow vegetable crops to dry out during the germination and seedling stage, and then ensure that the soil remains moist, but not wet, throughout the growing period. Use a straw mulch to keep moisture in the soil, add organic matter and suppress weeds.
Flowers
A spot of colour throughout the garden is always welcome, especially through winter. Brighten up your veggie patch with seedlings of Viola, Calendula, Alyssum and Marigolds. They will grow and flower over winter, some have edible petals or attract beneficial insects to the garden.
What to plant
Beetroot and Carrots
Beetroot likes plenty of manure and compost. Grow directly in the garden from seed and thin seedlings as required. Soak the corky seed overnight can improve germination. Beetroot will be woody and tough if watering is irregular.
Broad Beans
Broad beans should be planted directly into the garden as seed, in a rectangle or block. As they grow you can support them by placing some stakes at the corners and wrapping string around the outside of the entire crop. This will stop them from falling over. Easily grown in a sunny spot.
Bok Choi and Pak Choi
These grow quickly in rich, moist soil, ready for harvest in about 6 weeks.
Cauliflower, Cabbage, Broccoli, Brussels Sprouts
These plants all belong to the brassica group and require well-composted and heavily manured soil. Pick broccoli heads before they flower and the plant will keep producing side shoots. Protect cauliflower heads from yellowing by tying the side leaves over the head as it develops. Brussels sprouts will require staking as they grow, and be careful not to over fertilise with nitrogen. Cabbages benefit from crop rotation, as they are prone to soil-borne diseases.
Celery
March is a good month to get your celery going. You can begin to harvest individual stems after about 16 weeks.
Parsley and Silverbeet
These are regarded as year round crops and will tolerate being placed in the more shady part of your garden. Parsley and silverbeet will both grow well for the first year and then generally flower and seed in the second year. Allow to self-sow or remove and replace.
Peas and Snow Peas
Plant all peas as seed, directly into the garden. Climbing varieties will need trellis or stakes with string to climb on, and these should be put in place before you plant the seeds. Plant more seed than you think you will need, as not all will germinate, and protect from birds with netting as they emerge. Avoid watering the foliage, as peas are susceptible to mildew.
Rocket, Lettuce and Spinach
These greens love the cool autumn weather and will grow well in a rich, moist, well-composted soil. Plant seeds directly into the garden and pick as required.
Many different types of lettuce are available but are there are three basic types. Loose-leaf lettuces, such as oakleaf, do not form a heart and the leaves can be picked as they grow. Cos or romaine lettuces have an upright growth and the leaves may also be harvested as required. Iceberg style lettuces form a heart and are harvested as whole lettuce. Grow a few different types and plant more as they mature. Lettuce needs to be kept moist otherwise it will be bitter (and resentful).
Spinach grows well in the cooler months. Regular fertilising will avoid yellow leaves.
Spring Onions, Garlic and Onions
Spring onions can be grown all year and inter-planted with other crops, as they have good pest repellent qualities.
Onions are best started in trays and then moved out into the garden., This allows for better spacing. They require a moist, well-drained soil and should be kept weed free. Harvest onions when the tops fall over.
Garlic is usually planted in winter and harvested in summer. Plant individual cloves pointy end up about 7cm deep, 10cm apart. Harvest garlic as the leaves begin to yellow and die off. Garlic should be hung to dry for two weeks before storage.