Projects to prepare your garden for Winter
Make your own Biochar soil conditioner
Biochar is a type of charcoal formed when wood is burnt in an oxygen deprived fire. It has minimal nutritional value but its porosity and resistance to decomposition is of enormous value to the soil. Friends of mine at the Cape Otway Conservation Centre are applying biochar to revegetation sites instigating success where little was had before. To begin collect charcoal into a bucket, add water or worm tea to reduce dust and smash it into cent sized pieces with a hammer. To this add equal parts of compost and an organic liquid fertiliser such as a manure tea or seaweed concentrate. You should have a lumpy soup. Leave to soak for a few days before digging cup fulls in and around tree root zones or at the base of planting holes. You can also add biochar to working compost heaps. Over winter biochar will prevent nutrients from leaching out of the soil profile ensuring that plant roots can reach them when needed.
Plant a Green Manure crop
While the soil still has a little warmth and in patches of your garden that may be new or in need of a rest (particularly where you have grown potatoes or corn) consider sowing a green manure crop to help restore the nutritional and soil aggregation balance. I like to use a combination of species and have found in the past that mustard, peas, swan oats, millet and rape work particularly well in our area. You can often buy these in bulk from stockfeed suppliers. Simply prepare a seed sowing tilth, scatter the seeds and water to ensure seed/soil contact. Let the crop grow until it produces flower buds then slash or pull it leaving the green matter on the soil surface, scatter with blood and bone then mulch with straw so that some months later ( ideally in spring) you can plant through the mulch into renewed soil bursting with vitality.
Sow some Asian greens
I like Mizuna, it has crisp stems and produces prolific lettuce like cut leaf foliage throughout winter. Mibuna, Tatsoi, Wombok and Pak Choy are all worth germinating at this time of year and can be eaten as micro-herbs or left to develop and mixed into a warm salad. I also use the leaves as lining when making baked vegetable terrines. Each of the varieties that I have listed here can be direct sown but I achieve better results with Wombok if it is germinated first into seedlings trays and then grown on.
This is an eternal task which varies in method with the seasonal conditions. In winter your compost may be threatened by being too wet so ensure that it is appropriately covered trapping residual heat thereby hastening the decomposition process. Use heat retentive bricks, rocks and other dense materials to hold the cover in place. Winter compost benefits by turning and is a great way to get hot and sweaty in the cold weather.