Avocado growing isn't for wimps. Nor is it for every location, soil type or garden. On the other hand, once you do have a couple of avocado trees you should get hundreds of fruit every year. You'll never have to pay for smashed avocado on toast again.
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Avocados are fussy. Young ones die in frost, wind, heat, drought, or if it's too cold for too long, or from root rot from badly drained soil or ... just because. Old avocado trees may die from root rot, phytophthora spread from soles of shoes or mulch brought in, or because their massive root systems have suddenly met a band of clay or a seam of wet soil and don't like it. The trees die, top down, and often fast.
But young trees are most vulnerable. A young avocado's natural home is in an avocado forest. The seedlings grow in the shade, leaf litter and damp under the skirts of its vast parent, only reaching sunlight when they are two metres high or so, and several years old. By then they cope with heat and frost and - to a limited extent - wind.
If you don't have an avocado forest you'll need to make an avocado nursery: surround each tree with a circle of stakes, then drape shade cloth or fruit fly netting around and then over the stakes. This will protect them from wind, blazing sunlight, and give some cold protection. If you get frosts in winter (or even in mid November) you'll need to insulate them even more.
Ours first young avocado trees were protected by wire netting to keep the wallabies from eating them, then the netting was covered in old hessian sacks and the space between netting and tree loosely filled with bracken so that water could still penetrate. Other growers fill the space with loose felt or wool, but these can stop water penetrating so need to be used with drip irrigation or a bi-weekly watering the root area with a hose. Use what you have - old corn stalks or even many layers of bubble wrap around the trees. You can also buy water filled 'frost walls', though these are rarely tall enough to protect a young avocado.
Remove the insulation in summer, but do keep the trees still shaded so the leaves don't scorch in the heat, and make sure the soil stays moist.
And your avocado tree will always need mulch. The perfect avocado mulch may be one third wattle bark or 'slash' - small wattle branches, then a layer of loose lucerne, topped with a scatter of old hen manure and rock phosphate. Reapply as necessary. The tannin in the wattle will help prevent root rot, as will the various micro-organisms that your mulch will encourage. We mostly throw all garden waste under the avocado trees, including quite large branches from pruned or fallen trees. A few years later they have turned to soil, helped by the lyrebirds who aerate the soil as they look for lunch.
I planted my first avocado about 45 years ago. Our winters go down to minus nine degrees and everyone assumed we were crazy. As the trees grew and fruited, myths circulated that we had avocado fairies at the bottom of our garden, or kind earth spirits who approved of avocado toast, or at least a unique microclimate. But since then others have grown them in this climate, and those that were pampered for their first 5-8 years survived.
Our valley was slightly warmer than Canberra back then. But as Canberra grew more roads, more houses, more paving and enormous amounts of concrete, they all absorbed heat and reflected it back. Canberra is now usually warmer than we are.
Theoretically, if I can grow avocados, so can you. But we do have two advantages, as well as a willingness to tend the young trees. Our valley is protected from wind. Avocados do not like wind. Even large trees must have wind barriers. Secondly, well, we live in a valley. I'm not sure any of our land is level land, including the kitchen, where the concrete I poured for the slab slopes gently and any fallen fruit may eventually roll under the sofa. Our avocados are grown on sloping land, so the drainage is excellent. Avocados need moist soil, but do not survive wet feet.
But what we didn't have back then was soil. Like much of Canberra, we had shale and clay. There once had been soil, but 100 years of ploughing and rainstorms had washed it away. I planted the trees anyway, and slowly the soil built up with mulch, and the organisms that come with mulch incorporated the mulch into the clay and shale. Now you can dig for metres and still find rich black soil. Our soil grew with the avocados.
So there you are: if you think you'll be able to pamper your trees for at least five years, buy two avocado trees that will cross pollinate (try Daley's Nursery mail order). They may grow into 10-metre monsters over the decades, but you can keep avocados pruned lower, or even hedge them, but remember - if you want lots of avocados, you need lots of tree. Two mature trees may very well take up most of your backyard.
But after the trees are taller than you are, with trunks as wide as your knees, you throw on mulch, water now and then in droughts, add hen manure whenever you get around to it every few years, then pretty much forget them - apart from the picking. Avocados don't ripen till they are picked so you may even get avocados all year round if the currawongs don't get them first. Adult avocados are as hardy as the young ones are temperamental - except for their susceptibility to root rot. Harden your heart because, just possibly, even with all your care, your giant, flourishing avocado tree may die.
You need to be tough to grow avocadoes.
This is the week to:
Plant vast amounts of parsley, because even if we have a hot dry summer and the lettuces droop or bake, you can have parsley salad. It is impossible to have too much parley. Our possums agree.
Put netting over the parsley so the possums can't have parsley for breakfast every day. There are possum repellents you can spray on, but sadly this makes your parley as repellent to humans as it will be to possums. Physical barriers are best.
Choose cherry tomatoes instead of bigger fruiting varieties if you're not going to pick the harvest every day. Ripe tomatoes lure fruit fly better than any other fruit, but cherry tomatoes have tougher skins and are more fruit fly resistant. They are also fun, bite-size snacks for kids, and come in red, orange, yellow and if you are lucky, green or purple (the latter two cherry tomato varieties are rare, but do exist) You can have round cherry tomatoes, long ones or pear shaped, and some varieties even climb, too.
Pick the first roses of the season and put them in on your desk and kitchen bench to remind you that spring is here even if you are office bound during the day.
Listen to the frogs. If you hear an interesting one, Google 'frog census' and send it in so Aussie frog locations can be mapped.
Watch the ants. Ants seem to be more accurate in droughts than the weather bureau. If the ants are building castles and covering them with bark, it's going to rain.