As fertiliser costs continue to increase, farmers are looking for cheaper ways to nourish their soil and plants. We speak to Stephanie Mullins, programme manager at urban farming organisation SEED, who unpacks how you can save money while still providing the optimal amount of nutrients required by your operation.
Mullins says that there are multiple reasons for farmers to switch from more traditional chemical fertilisers to organic or natural fertilisers. She explains that cost is only one aspect of fertilisation.
“It is beneficial for the soil and thus, our environment. It also benefits the individual and [that] is because when we are practising non-organic methods, we’re usually using chemicals that affect the health of those applying it.”
Mullins also explains that there are no hard and fast rules around what you should be using for making fertilisers.
“It’s more about what’s around you, what you have readily available, or within close proximity. More often than not, it will be more beneficial for your soil to use what’s around instead of bringing in other foreign materials.”
Elements that can be used for fertilisers include grass and plant clippings left over from pruning, anything organic or what Mullins calls “green growing material”, that can be broken down or turned into a tea.
“You can also use animal manure, from chickens, cows and horses. And there are many different methods in which you can use them.”
Feeding your soil
Mullins says that, when farmers think of fertiliser, they need to think of how they can grow the microorganisms in their soil, as well as the minerals and nutrients.
“Instead of thinking about feeding your plant, you [should] think about how you feed the soil. Because the soil, in turn, feeds the plant.So when you add natural organic materials to your soils and they break down, they release all their nutrients into the soil which are readily available for your plants to use.”
Natural fertiliser systems and elements are numerous and include vermiculture, seaweed fertiliser, composting, etc. Mullins is a big fan of vermiculture specifically, as the results are often amazing.
“Worm farms are one of the most popular fertiliser systems, specifically among households and small-scale farmers. I’ve also seen it used at a large scale. The outputs of a worm farm are so amazing. Farmers make a fertiliser tea and feed their plants.
Also, worm poop is referred to as black gold, and it’s used in many different methods, so you can put it in your compost, you can make a tea with it, and you can also mix it into your soil.”
How you fertilise, says Mullins, depends largely on the size of your area. For larger-scale farmers, Mullins recommends composting. She explains that compost can be made with any natural material, which then breaks down, leaving only the nutrients behind.
“Farms are great for composting, whereas, in households, you can’t really make a compost pile because you can’t generate enough matter for a one-metre squared by one-metre high pile, and that’s the minimum requirement. So for farms, I would recommend composting as your best friend.”
Growing your fertility
Many people grow their fertiliser, meaning farmers, use certain companion plants as live fertilisers that feed their soil. Companion plants have different functions, depending on your soil needs.
“All-purpose plants and ones that home gardeners love, as well as medium to large scale farmers, is mostly your comfrey, stinging nettle, borage, your yarrow, and your legumes, which speaks to all the different nutrients that you need in your fertility schedule.”
The primary nutrients required by the soil include nitrogen, phosphorus, and potassium. The amount of these elements you require, says Mullins, depends on the kind of operation you have.
“Do you grow fruits? Are there leafy crops? Are there root crops? That will determine what kind of fertility you implement in your operation.”
Nitrogen, she explains, is important for photosynthesis, and is mostly found in leguminous plants, like peas and other pod vegetables. Comfrey is also a good source of nitrogen, as well as seaweed and stinging nettle.
“Potassium is good for the development of fruits. You’ll find the nutrients you need for potassium in your borage, yarrow, carrot leaf tops, and clover that covers the ground.”
Root growth, she says, benefits from phosphates, which is where yarrows are useful again. She also recommends marigolds and mustard.
“These plants are called dynamic accumulators because they accumulate a lot of different minerals and nutrients for your plants.”
Start with what you have
Mullins’ primary recommendation for farmers is to start with what they have.
“There are so many natural methods to use. It’s just finding the one that suits your schedule best, whether you are large or small scale. And really, the natural way, the organic way of farming, is much more affordable than the traditional way. You’re not spending money on any fertilisers or pest control, because along with your organic and natural fertilisers, you also plant to manage and control your pests.”
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