This summer has been a good one for gardeners, with lots of heat and rain providing ideal conditions for growth. However, I have to admit the subtropical conditions have left me a little exhausted. I can see why outdoor workers in tropical countries seem to work at a leisurely pace; it’s pretty much impossible to work any faster in these conditions.
As a consequence, the veggie garden is also looking a little tired; some crops have done their dash quicker than usual in the heat, while others haven’t been fertilised enough to keep up with the growth; or pests and diseases have taken hold. Replacement crops haven’t gone in soon enough and crops that need long-term attention, like the greenhouse tomatoes, are now looking pretty ratty.
Fortunately, with the temperatures dropping, gardening seems more appealing. Just in time, as now we need to get organised for a good autumn and winter garden. The first job is to prune summer fruit trees before the leaves fall off. This is the best time to prune in order to avoid fungal diseases and reduce the amount of carbohydrates flowing back into the roots, which would reduce vigour next spring. Hedge pruning is also recommended at this time of year for the same reason. It is a great time to take cuttings as well.
The moist, warm soil and cooler air temperatures are ideal for planting any trees, shrubs and perennials. Spring flowering bulbs – such as daffodils, freesias, iris and tulips – can go in too. Alternatively, use the old gardeners’ trick of putting them in the fridge for six weeks first to get better flowering. Winter flowering annuals such as pansies and calendulas can be planted now, as can the first of the winter veggie crops; peas, brassicas, carrots, spinach, silverbeet and beetroot.
Look at the back of your fertiliser packets for the NPK ratios. Avoid using fertilisers that are high in nitrogen (N), as nitrogen produces soft, sappy growth that is less resistant to pests, diseases and frost. Instead, look for fertilisers high in potassium (K) as this strengthens plant cells and helps harden them off. Phosphorus (P) is also important on all plant types (except the Protea family) once they shift their resources from top growth to root growth.
Regular readers of this column will know that I’m a committed exponent of mulch. It improves soil in so many ways and reduces your workload by suppressing weeds. Autumn is a good time to bed down your ornamental gardens, and any veggie gardens that won’t be used in winter, under a thick layer of mulch. For ornamental gardens a woody mulch is best, but veggie gardens can be mulched with just about anything at this time of year.
Come spring, the mulch will have been mostly worked in by the worms. Alternatively, plant barley, lupin, mustard or other green crops as cover crops. These can be turned under in later winter to feed the soil and suppress soil pests.
Reducing pest numbers now will reduce the amount of over-wintering bugs that start the cycle next season. One of the best ways to do this is prune or pull out any infested plant material and either compost or use a mower to mulch them into the lawn. Alternatively, burn them or put them through a mulcher. If you’ve used cardboard or material rings around your apple tree trunks for codling moth, now is the time to remove and burn them as the moths will be pupating in these. Passionvine hopper lay their eggs in serrated rows on thin twiggy material, so keep an eye out for this, prune off and burn. Get all these jobs done before winter and you can spend most of that dreary season in front of a roaring fire with a good book, or for the lucky ones, on some tropical beach.