So much of what is written about growing food is based on commercial information. The methods of broadscale monocultures are scaled down to home gardens, based on the experience and research of commercial food production. But this may not be the best way to go about growing things in a local home garden.
Fruit trees are a good example of what I mean. In commercial orchards, trees are grown and maintained in a very uniform way. The aim is to get a large quantity of uniform fruit for market, ripening at the same time on multiple trees in plantations of dozens or hundreds of trees. The spraying, pruning, picking and processing of the fruit is streamlined to reduce costs to the grower. The trees all grow genetically identical fruit on selected rootstocks to reduce pest and disease problems. Such problems are concentrated by growing only one kind of plant in such mass plantings as orchards.
These problems for the most part do not apply to home growers. Further, the predictability of known varieties, those which are sold in bulk by supermarkets and grocers, are of benefit to mass production, allowing growers to systematically produce crops at set times of year. The existence of such monocultures are the main cause of chemical pesticide use in agriculture and horticulture. Large scale operations require mechanised simple solutions for economic reasons.
When European settlers first arrived in Australia, they were forced to select and breed new varieties of plants and animals for the new conditions here. The climate, seasons and soils were so alien to their experience that varieties from “home” were not as predictable or productive as they were used to. Now faced with changes to climate, including temperature and weather patterns, we must begin to select new varieties that can cope with altered conditions.
Luckily for us, nature has a means of doing so quite easily: seeds. Every seed contains a variation on the genetics of it’s parent plant. Sexual reproduction in plants allows them to adapt to new environments and survive, and there is no reason home gardeners can’t take advantage of that natural adaptability. But the only way to do that is by letting those seeds grow. Existing plants can’t adapt to changed conditions in the same way their offsrping may be able to.
Many fruits we eat contain seeds, and there is no reason a home gardener can’t plant those seeds and grow new varieties of fruit which are unknown in the world. The vegetatively reproduced commercial varieties are well known to us for reasons of consumer preference, but mostly for shelf life, transportability, and ease of production by large scale growers. The price of fruit at market is influenced by season, but also by costs to the producers. Home gardeners, by having only one or two of a particular kind of fruit tree can avoid the broad scale pest and disease problems of the commercial growers, and by growing seedlings, could find new varieties with resistance to pests, diseases, or changed climatic conditions, such as lower water availability or reduced chilling periods.
Planting the seeds of the apples we eat, for example, will produce seedling apple trees. If we plant those seedlings in the ground, we find which are best suited to our actual soils and other conditions. The ones that thrive are evidently more suited to our specific location. Leaving them to mature and produce fruit will give us further information about their suitability for particular areas and seasons, and good record keeping will allow us to share that information with others. Finally, when the fruit appears, and admittedly this may be five or more years after planting seeds, we can pick it, and taste it, and decide whether it is an improvement on what we get in the supermarket.
In the vast majority of cases, if the fruit is not to our taste, or without some particular use, it can often be grafted with something more to our liking. The chances of it being radically different from the fruit we first took seeds from is very small, because of the way fruit is grown. The plants that pollinated the apple we bought are virtually identical, so the gene pool is quite small. But other features, such as disease tolerance, could make it a superior plant, even if the taste is exactly the same. But there is a chance it could taste better, be sweeter, have bigger fruit, ripen earlier or later, or any number of slight variations which may be improvements on the original. And no matter what, you get to name the new variety whatever you wish, as every seedling is a new variety, no matter how similar to it’s parents.
In the case of nuts, one of the major concerns for growers is uniformity of size, and that is one of the main reasons they grow selected varieties, so they know their harvest will be uniform. This carries over to processors, who often have machinery for shelling specific sizes. If the nuts aren’t the right siz, they won’t buy them. Most of the nuts in their shells on the retail market are “non uniform” for this reason. But if you’re going to sit around at Christmas with a nutcracker opening them by hand, what difference does it make to you?
There are restrictions as far as what will grow where. But when growing seedlings for basically no outlay, you can try whatever you want. Avocadoes and Macadamias grow quite happily in Melbourne, for example, but as far as I know, Brazil Nuts do not. There is no reason not to plant a few and see what happens, though. Sure, the frost might get to them, but then again, you may grow the first frost tolerant Brazil nut in the world. If it can be done, it won’t happen by sticking with the known varieties, that’s for sure, it needs seed-generated biodiversity for changes to happen, and those changes might be needed quite soon.
I’ve mentioned before that some of the most popular varieties, for example Granny Smith Apples, began as chance seedlings. If everyone with a garden grew a few seedling fruit trees, imagine how much genetic diversity would be cultivated in a single suburb, not to mention how much food could be produced. Sure, the tree you grow may not be your favourite orange, or pear, the walnuts your tree produces may be smaller than those in the shops, the mandarins might be seedier than you’d prefer, but surely it’s better than no food at all? And if it costs nothing, there’s nothing to lose.
So, keep your seeds in a paper bag, maybe even in the fridge, then plant them out in spring. Except Avocadoes which can go in any time, really, though they may not grow until the weather is warm. Give it a go. Even if you don’t have space for a Walnut tree, you could always sneak it in to the nature strip somewhere.