Biologicals

A biological fertiliser, or biofertiliser, contains living microbes that help plants get at nutrients. Some bacteria fix nitrogen from the air, others release phosphorus and potassium locked up in the soil, and mycorrhizal fungi extend the root system to reach more phosphorus and water. Our BioNPK Powder S contains microbes that convert nitrogen, phosphorus and potassium into plant-available forms, plus mycorrhizal fungi and Trichoderma, and is applied as a seed coating or soil spray.

No, and we don't recommend using one that way. Biologicals may help plants make better use of the nutrients already in the soil and in your fertiliser, but they can't supply nutrients that simply aren't there. Base your program on a soil test, correct any deficiencies, and use a biological alongside it, which may improve root growth and nutrient uptake.

A legume inoculant contains the specific rhizobia bacteria a legume needs to form nodules and fix nitrogen, and each legume group needs its own strain, such as Group C for sub clover. A broad-spectrum biological such as BioNPK Powder S contains a mix of microbes intended for a wide range of crops and pastures. It doesn't replace inoculant; legumes still need their correct rhizobia.

Most go on the seed or onto the soil. Many of our pasture mixes come pre-coated with BioNPK Powder S. As a soil treatment it's sprayed onto bare soil at 0.25 kg/ha in 100–400 L of water per hectare, before or at sowing. Dissolve it in a separate container first, add it to the tank last, and spray it out the same day.

Some can be, but check before you buy. Standards differ between certifiers, so confirm with your own certifying body that any biological input, including BioNPK Powder S, is allowed under your certification before you use it. Ask the supplier for the product's documentation and keep it with your farm records for audit.

Mycorrhizal fungi colonise plant roots and grow fine threads far into the soil, taking up phosphorus and water the roots can't reach and trading them for plant sugars. That matters in WA, where many soils are old and low in available phosphorus. Most pasture grasses, clovers and medics form these partnerships, but brassicas and lupins don't, and long fallows reduce fungal numbers.

Treat them as living products. Store them sealed in a cool, dry, well-ventilated place out of direct sun, ideally between 5°C and 30°C, and use them before the expiry date. Don't tank-mix with strongly biocidal products, don't leave mixed spray standing, and wear gloves and a dust mask when handling powder.

Run a simple strip trial. Alternate treated and untreated strips, at least four of each, with the same seed, fertiliser and management, then compare establishment, root growth, dry matter or yield, and ideally plant tissue tests. Results from biologicals vary with soil type, moisture and season, so a trial over a couple of seasons on your own soil tells you more than any brochure.

They can, but conditions matter. Soil microbes need moisture and some organic matter to survive and multiply, so results are usually better when the product goes out at or just before sowing into moist soil, rather than onto dry sand weeks before the break. Keeping groundcover and living roots in the paddock gives the microbes somewhere to live.

Feed and house the soil life. Keep living roots in the ground for as much of the year as possible, maintain groundcover, avoid unnecessary cultivation, and grow a diversity of plants, including legumes and deep-rooted species, through pasture phases or cover crops. Correct pH and nutrient deficiencies too. Biological products add beneficial microbes, but they last longer where that habitat exists.