So you’re resolved to grow the best darn vegetables ever. You’re on a mission to feed your family nutrient-dense, organic, home-grown food, to stick it to the supermarket, and to hopefully have enough to share with friends and neighbours too.
Getting your soil’s pH balanced can help a lot. Here’s how to do it:
Healthy plants should be able to get all (yep, ALL) of the nutrients they need from the soil.
But if your soil is too acidic or too alkaline, those nutrients won’t be available, no matter how much fertiliser you add.
Acidity has a strong effect on the ability of plants to take up soil nutrients as well as upon the wellbeing of soil organisms.
Most nutrients that plants need can be chemically assimilated when the pH of the soil solution ranges from 6.0 to 7.5.
So getting your soil pH right is absolutely essential, if you want nutrient-dense veggies.
pH is a measure of the acidity vs the alkalinity of the soil, and determines the capacity of that soil to exchange nutrients with plants growing in it.
As well as affecting the ability of plants to uptake nutrient by both chemical and biological processes, the pH also affects the diversity and species of soil microbiology.
pH is usually measured on a scale of 1-14:
Not all plants are the same – different crops prefer different levels of acidity – for example:
So it depends what you’re growing as to what pH you want to nudge your soils towards. Keep in mind that most annual veggies prefer a bacterially dominated soil, which is leaning towards a pH of 7 – 7.5
Soil science and the nature and intricacies of the soil food web is a VERY BIG topic. And an awesome one, too. But for now, let’s leave it at that.
Basically, if you want a garden bed that the majority of your veggies will thrive in, you want to create soil that has a pH of 7 – 7.5.
Firstly, get your hands on a soil pH test kit. These can be got from garden centres, or online.
So you’ve tested your soil in six places and you’ve found out that it’s generally a pH of… whatever it is.
Here’s some tips on how you can balance your soil…
Add green manure crops into your rotation with more frequency.
Add organic matter in the form of a well balanced, pH neutral compost… adding humus is the best way of changing pH… let the biology do the work!!
Add agricultural lime (not builders lime!). As a rule of thumb, carefully apply 100g to each meter squared. NOTE lime can only be accurately applied if a total mineral test is performed. It will take a while to increase the pH this way – you should see a change in the pH within 6 months. Be careful not to over apply.
Add Dolomite – BUT it contains Magnesium, which if it is already present in large quantities, could block other minerals. Again, a total mineral test is a good idea before doing this.
This soil will be harder to rebalance
Add organic matter such as pine needles or decomposed tree leaves.
Add green manure crops into your rotation with more frequency
There’s other, more in-depth roads you can go down with mineral testing for your soil (we recommend Swep Laboratories if you’re going this road).
But as you can hopefully see from the info above, balancing your soil’s pH is a great first step to healthy veggies.
In short, balancing your soil’s pH is a short-cut to growing healthy food.
Once you’re on your way with good soil pH, it’s much easier to treat mineral deficiencies if they crop up in your plants.
Because now, you’ve created a soil environment where the plants can suck up the goodness they need, once you give it to them.
Lastly, if you live nearish to Sydney NSW, join us for a Serious Backyard Veggies course with Michael Hewins sometime and learn more about making great soil.
Michael’s an amazing organic market gardener who’s passionate about de-mystifying the process of growing nutrient-dense veggies, starting with your garden’s soil.
Good luck out there, gardeners!
May your corn rise high, your potatoes be fulsome and your tomatoes, berries and salad greens be so plentiful you’ve enough for everyone on your street…
Big thanks to Michael Hewins for his contributions on this how-to.