Help your garden thrive this summer by doing the groundwork now

It’s the season of foggy vistas, crisp temperatures and for coveting sunny yellow bulbs like winter aconites. But unless the beaming flowers of this difficult-to-acquire buttercup relative are already erupting from their leafy ruffs and your just-right soil, your timing is wrong for this year at least.

Better to concentrate on what you can do now. And one of the most pressing things is to get ready for summer. Even the most casual glance at the recent temperatures currently in some parts of the United States might give you pause. While brutal summer heat in southern California is nothing new, the region’s record-breaking temperatures this month again highlight how climate change is making heatwaves hotter and more frequent.

Many Victorian gardeners had an easier go of things last summer thanks to La Nina and the relatively mild, moist conditions that weather pattern generated. But don’t be lulled into complacency. The Bureau of Meteorology is already forecasting above-median maximum temperatures for most of Victoria for August to October, and says Australia’s climate is getting hotter. It has warmed by about 1.44°C over the last century, with southern Australia experiencing a reduction of 10 to 20 per cent in cool season (April to October) rainfall in recent decades.

So what can a gardener do in mid-winter to prepare for this? Number one is to get planting. Plants not only create shade, but lower temperatures by evaporating water through their leaves into the atmosphere. By planting now, the roots will have the chance to get established before summer kicks in.

Wide-canopy trees and vines-over-pergolas are obvious shade-providing contenders. But exactly what to choose for shade will depend on the conditions of your site. Some offerings, such as table grape vines – available in nurseries now – have the added bonus of providing food as well. But as fast-growing and tough as an edible grape vine can be, it will be some years before they – or any shade-yielding plants – actually provide leafy summer cover. In the meantime you might think about manipulating what you already have.

By removing the lower branches of a mature tree you can lift its canopy in such a way that you can fashion a shady seating area below. Up-pruned trees often look better too. But never cut a branch flush to the trunk. Instead, make sure to leave intact the slight bulge – or branch collar – where the branch meets the trunk as it is the interlocking cells contained within this collar that will help heal the pruning cut.

Now is a good time to prune deciduous trees as they have no leaves, but evergreens can be left another month or so.

While now is a good time to prune deciduous trees as they are dormant and have no leaves to obscure their branch structure, evergreen trees can be left another month or so when the weather is starting to get warmer and their cutting wounds will heal faster.

Improving the quality of your soil will also help your garden perform better in times of heat and water stress. Helena Buxton recently ran a composting workshop that highlighted how you can turn garden waste into rich compost in less than two months, which means if you build layers of different sorts of carbon and nitrogen-rich materials into a hot pile now you could have compost at the ready in early spring. For the fastest results, Buxton shreds or crushes all her waste into the smallest of pieces, adds manure, keeps her pile moist (but not wet), turns it to add oxygen and heavily insulates it with hay bales, including over the top so that no part of the pile is left exposed.