When it's 41C in the paddocks and 4,600,926 native pollistes wasps abandon their nests up in the gorge and move into the kiwi fruit on our pergola, and the goannas migrate into the orchard groves around the house, you know you have succeeded in making your place the coolest habitat around. Literally.
Or relatively. On hot, dry days the garden around our house is about 10C cooler than in the open country around us. Sometimes it's as much as 14C, or as little as 8C when there's a hot north westerly blowing through the trees, though as our garden is designed to slow down the winds before they reach the inner garden and the house, wind also isn't as much of a problem here.
The 28C outside our front door last weekend was hot, but far more bearable for us, as well as the wasps and goannas, than 41C.
So how can you cool your garden ?
There is shade, there is dappled shade, and there is deep shade. We go for deep shade in summer, which means "layers" of trees. Each layer traps another barrier of air - the more layers on insulation above you, the cooler it is below.
So we have tall avocadoes, pecans, or pears, with understory lychees, macadamia, or citrus, then shade tolerant tamarillos or tree dahlias below.
There's one proviso about shade though - make sure that the trees and shrubbery don't block the breezes to the house. You can either prune off low branches, so the trees are shaped more like an umbrella than a Christmas tree, or, especially in humid areas, go for high thin trunked trees like palms that will grow up, up and up before they grow out.
In other words, it isn't quite as simple as just "plant". There's a lot of planning, including choice of trees that will eventually grow to different heights and tolerate some shade, too.
Stick a wet tea towel over the fan, and you'll cool the room. Have moist mulch under the trees, and the evaporating moisture in the breeze will cool your garden. So will micro jets and even drippers…unless they add to the humidity. Moisture only cools when it's dry heat, not humid heat, and when there is actually a breeze, or wind to help evaporation. On a still, humid day the extra moisture can make a stroll your garden feel like your are walking through warm soup.
3. Find the heat source and block it
Add bitumen roads, stone or brick walls, paving, concrete footpaths, or roof tops radiating heat and your neighbourhood gets hotter. Try to block off the biggest sources of heat: a hedge or shrubs to guard you from the stored and effected heat in the road, high trees to shelter you from the reflected heat of neighbour's roofing. Cover your paving with vines; shade your walls with shrubs.
And make them deciduous. Summer is lashing us just now - last weekend the possums even moved out of our roof space, and made themselves more comfortable on the bedroom patio - but in a few months the winter winds will bite, and we'll be longing for more sunlight, hot paving and warm stone walls.
This week I am
- Planting purple garlic cloves, to grow into a purple garlic crop to harvest next December…or maybe planting them, depending on the weather and my workload. The 'purple' by the way refers to the colour of the inner papery covering, not the cloves.
- Hoping that some of the giant magnolia grandiflora flowers will be low enough to pick with a long handled fruit picker, so we can put them in vases indoors. All the ones blooming so far would need a cherry picker to harvest them.
- Deciding that a mid-summer tomato possibly contains all the vitamins and minerals necessary to help the body tolerate summer heat. Why else should they be so irresistible? Just add black pepper - lot of black pepper - and they need nothing else.
- About to pull the cloth fruit protectors off the Jonathon apples and see if I do have a crop or if they have fallen off, rotted or simply vanished into ooze.
- Picking more finger limes. The jewelled caviar like insides are brilliant with smoked salmon, or used to stuff whole fish before you grill or bake it.
- Watching the grass grow again after the rain, and listening to the wombats chomp it – until the next dry heatwave, when the grass will vanish again. And the wombats will blame us.