Take 15–20 cores in a zig-zag across one uniform area, all to the same depth (about 15–20 cm), skip edges and odd spots, mix in a clean plastic bucket and send about 0.5 kg.
One handful of soil from one spot is not a soil test. Here is how to take a sample the laboratory can actually use.
Pick one uniform area of your field. Walk across it in a zig-zag, and take fifteen to twenty small cores, every one to the same depth, about fifteen to twenty centimetres.
Skip the edges, the ground near trees, old manure heaps and wet hollows.
Mix all the cores in a clean plastic bucket, not a galvanised one, then send about half a kilogram, labelled with the field and your next crop.
How to read the report is in our long video, and at laisha.ai.
A maize plant shows what it is short of. The one rule that narrows the search (mobile nutrients show on old leaves, immobile ones on new leaves), the signs and causes of nitrogen, phosphorus, potassium, sulphur, magnesium and zinc deficiency, the look-alikes (herbicide injury, leaf diseases, genetic stripes, waterlogging, cold), and how to confirm with tissue and soil tests before you act.
How to Grow Maize →
The brown planthopper (Nilaparvata lugens) is one of the most destructive insects of rice in Asia, and outbreaks are very often caused by the insecticides meant to stop them. How to recognise the insect, hopperburn and the grassy stunt and ragged stunt viruses, why outbreaks happen, scouting and action thresholds, the natural enemies that keep it down, crop management (resistant varieties, split nitrogen, alleys, alternate wetting and drying), and choosing insecticides by IRAC group while avoiding pyrethroids.
Brown planthopper →
Composting turns farm waste into organic matter that improves soil structure, holds water and returns nutrients. How composting works (start-up, the hot phase at 55–65 °C, cooling, curing), the right mix of browns and greens (C:N about 25–30:1), moisture and aeration, the hot phase that kills weed seeds and pathogens, fixing smelly and cold heaps, what to keep out (including straw and manure carrying persistent herbicide residues), how to tell when compost is mature, and how to use compost and vermicompost safely.
Soil organic matter, humus and the C:N ratio →
Drip irrigation delivers water drop by drop to the root zone, with application efficiencies around 90% when well designed and run. The parts of a drip system from backflow preventer and filters to laterals, drip tape and flush valves, choosing emitters and spacing for sandy, loam and clay soils, working out run time from crop water use with a worked example, fertigation, preventing physical, chemical and biological clogging, the one-minute cup test for uniformity, and costs and returns.
Irrigation methods: surface, sprinkler and drip →
Whiteflies breed fast on tomato, chilli, aubergine, cucurbits and cotton, cover leaves with honeydew and sooty mould, and Bemisia tabaci spreads damaging viruses such as tomato yellow leaf curl. How to tell Bemisia tabaci from the greenhouse whitefly and recognise each life stage, the damage and viruses, scouting with yellow sticky cards and leaf checks, keeping them out with clean seedlings, netting and hygiene, the natural enemies that control them, and choosing insecticides by IRAC group with rotation against resistance.
Silverleaf whitefly (Bemisia whitefly) →
A soil test replaces fertiliser guesswork with a measurement. When to sample, how to divide the farm into uniform areas, how to take a representative sample, labelling and choosing an accredited laboratory, how to read the report (pH, lime requirement, EC, phosphorus and potassium, extraction methods, organic carbon, why nitrogen is different), and how to turn it into a fertiliser plan, including grid and zone sampling.
Soil testing and fertiliser recommendation →
Purple blotch (Alternaria porri) and Stemphylium leaf blight (Stemphylium vesicarium) strip onion leaves early in warm, humid regions worldwide. How to recognise each, tell them apart and from downy mildew, the leaf-wetness weather that drives them, prevention, fungicides by FRAC group with resistance in Stemphylium, and curing and storing bulbs.
Purple blotch of onion →
Late blight (Phytophthora infestans) caused the Irish potato famine and is still one of the most damaging diseases of potato and tomato worldwide. How to recognise it on leaves, stems, tubers and fruit, tell it from early blight, read blight weather, find where infection comes from, prevent it, choose fungicides by FRAC group with resistance management, and protect tubers at harvest and in store.
Late blight of potato and tomato →
Aphids are on almost every crop in the world. How to recognise an aphid in seconds, tell it from whiteflies, mealybugs and thrips, why colonies double in days, the three kinds of damage including virus transmission, scouting and action thresholds, the natural enemies that control aphids for free, cultural control before spraying, and choosing insecticides by IRAC group to slow resistance.
Aphids: biology, virus spread and control →
Most of a wheat crop's yield is decided in its first few weeks. This step-by-step guide covers the sowing window for winter and spring wheat, seedbed or zero-till drilling, seed testing and treatment, the seed rate formula with a worked example, sowing depth and spacing, phosphorus and split nitrogen, the first irrigation, weed control from sowing day, and how to count plants three weeks later.
How to Grow Wheat →
Yellow leaves on a tomato plant can mean anything from "completely normal" to a soil-borne disease. This video walks through the 7 most common causes, how to tell them apart from the leaf itself, and what to do about each one.
How to Grow Tomato →
US$10 (approx. ₹960) a month · one price worldwide · cancel any time
An AI operating system for agriculture: free guides, manuals and tools written for every country.