All farming has its challenges. For organic farmers, one such difficulty has been maintaining soil fertility without the use of synthetic fertilisers. But if the organics industry in NZ is to achieve its ambition to contribute $4.2 billion to GDP by 2030, then organic farmers and growers need to not only maintain soil fertility, but to increase it.
Natural NPK fertilisers can help increase soil fertility and pasture growth for organic farmers.
To date, there have been a shortage of quality, natural fertiliser products available in NZ to help with this issue. Especially lacking have been BioGro-certified sources of macronutrients like nitrogen, potassium, and phosphorus (NPK).
However, things are changing. And this is excellent news for not only organic farmers, but for those of a like mind who are looking for more natural fertilisers to boost their soil fertility while looking after their soil health and the environment.
Natural, BioGro-certified nitrogen
Nitrogen is the nutrient that is most in demand by plants. They need it to form the amino acids that make their proteins and their DNA. Plants also need nitrogen to make the chlorophyll they use for photosynthesis. So, it’s easy to see how a deficiency can stunt growth.
Until recently, fishmeal has been one product organic farmers have turned to in order to meet the nitrogen requirements of their pasture and crops. But it’s not the ideal source being only 10% nitrogen (N:10). And that’s not to mention the odour!
So the availability of natural nitrogen fertilisers like Protamin N13 is a game-changer. It has a higher organic nitrogen content (13%), but crucially, it does not release all its nutrients at once. The fast, medium, and slow release pattern means that nitrogen is available to plants for a longer time during their growth, and less nutrients are lost to the environment.
Apart from supplying nitrogen, Protamin N13 is high in organic carbon and has a high water absorption capacity, so it has a biostimulant effect on soil microbes. This in turn improves nutrient uptake and promotes healthy root growth and photosynthesis.
Being a co-product of the leather industry, Protamin N13 is exactly the kind of natural fertiliser needed to help organic farmers meet their industry goals. Another fertiliser of this ilk is a natural BioGro-certified source of potassium called Phosta K.
Natural BioGro-certified potassium
Potassium controls the transport of water around plants, and regulates the opening and closing of the stomata in the leaves so that photosynthesis can proceed normally. It also activates enzymes which transport nutrients like nitrates, phosphates, calcium, and magnesium around the plant. So potassium maintains optimum utilisation of any applied nitrogen and phosphate fertilisers.
A go-to source of natural potassium has been sulphate of potash (SOP), typically mined from underground salt deposits. But as mentioned above, another option now available is Phosta K, a by-product of the sugarcane industry. Being made from 100% plant-based materials, it’s kind to soil biology, and contains nitrogen, phosphorus, calcium, magnesium and the trace elements copper, molybdenum, sodium, manganese, zinc, and copper. So it’s more than simply a source of potassium. And like Protamin N13, the nutrients are not released all at once.
So natural alternatives for the ‘N’ and ‘K’ macronutrients are now available, but what about the ‘P’ (phosphorus)?
Natural BioGro-certified phosphorus
Plants need phosphorus in the form of phosphates. It’s vital for photosynthesis, plant development, and heredity processes, and a continuous, regular supply is best.
Two natural sources of phosphorus which deliver their nutrients in this way are guano, sourced from mineral-rich deposits of seabirds, and RPR (reactive phosphate rock). While these products aren’t necessarily new to the market, they’re a natural way of replenishing phosphorus levels wherever animal and plant products are removed from a system. Importantly for organic farmers, both guano and RPR contain very low levels of undesirable heavy metals and flouride, often found in conventional phosphate fertilisers.
No need to do without NPK
In sum, organic farmers and growers need no longer compromise their soil fertility because natural sources of NPK nutrients aren’t available. And any increase in soil fertility will go some way toward helping the organics industry achieve their ambitious GDP targets.
This article was published in the Coast & Country News.
