I feel blessed to live in a temperate climate where we get to experience the wonder of autumn in all its shades every year. Every autumn is different, even more so as our climate changes and becomes less predictable. As gardeners it teaches us to observe closely and to act in accordance with what each season, each day presents, not with arbitrary dates on a calendar.
Autumn is a busy time, even as the plants and soil begin to wind down and cool down for the coming winter. In the veggie garden we are in full harvest mode as well as madly propagating seeds, saving seeds, pulling out spent crops and preparing ground for the next round of veggies. There is a window of opportunity. Some years, very short, between when it is too hot and dry to plant the cool season crops and when the soil has cooled down too much and things stop growing.
If you are growing your own seedlings from seed, you need to plan at least six weeks ahead of time. I try and have my garlic (depending on the variety) in ground by May and my goal is to have all my other winter and spring crops in the ground before the garlic. This means that I start sowing my cool season crops from late December through to early April. There are challenges in planting new seedlings out in the garden at this time. The warmer weather means that pests and diseases that thrive in summer have not yet died off so we need to protect our crops through this transition time.
The trick to a good summer-autumn transition is having ground that is resting and ready for planting from January onwards. The challenge of growing in a small garden is leaving space for the coming seasons crops and not planting out every square inch of ground. It is heart breaking to have to rip out your still productive tomatoes, zucchinis, cucumbers and other yummy summer crops so that you can get your brassicas in on time! You can ensure that you have ground ready in autumn by resting a patch over summer. This involves adding a good amount of organic compost in spring as well as a heavy layer of mulch to keep the soil moist and protected through the heat of summer and resisting the temptation to ‘just put a quick crop of something in’.
Another way to not only rest but also build up healthy soil over summer is with the help of a green manure crop. A green manure crop is a diverse mixture of annual plants including legumes (for adding nitrogen) and grasses (for biomass) that you sow as seed directly into the garden. It can also include plants in the mustard and allium families that help to bio-fumigate the soil. The greater the variety of plants in your green manure crop, the healthier and more nutrient rich your soil will become. In spring or early summer you can sow the green manure crop in the portion of your garden that will become your autumn garden. Once the green manure crop starts flowering, it can be dug in and covered with a thick layer of mulch allowing 6-8 weeks for the luscious biomass to break down, feed the soil and be ready for planting out with crops for the cooler seasons. Heavy feeding crops such as brassicas do especially well following a green manure crop.