How to grow groundnut

Decide this early — in the months before the rains, and settle which field you will use by about two weeks before you sow. Pick a field where groundnut — and other legumes like beans or soya — did not grow last season. Land coming out of maize, sorghum or millet is ideal, because the cereal starves the groundnut diseases that live in the soil.

Choose light, well-drained land; sandy loam is best. Avoid heavy clay and low, wet spots — there the pods rot and won't lift cleanly.

Feel the soil when it is dry. If it sets hard or forms a crust, plan to break it up well: pegs cannot push into a hard or crusting soil, so the pods never set.

Plan to shell your seed just before planting, not weeks ahead — shelled kernels lose their strength quickly and bruise easily.

Buy clean, well-filled seed of a known variety — plump kernels, none shrivelled, cracked, mouldy or discoloured. Your recommendation gives the type and the seed rate for your field.

Buy it still in the shell if you can, and shell it just before planting. A bruised or split kernel rots in the ground instead of growing.

Buy the basal fertiliser (P and K) your recommendation gives. Groundnut needs phosphorus and potassium, not a nitrogen fertiliser — the plant makes its own nitrogen.

Buy gypsum (calcium sulphate) now for pegging time — you will need about 200–500 kg per hectare spread over the rows at flowering. Shops run out, so get it early.

On land that has not grown groundnut in the last few years, buy Rhizobium inoculant — the packet of living bacteria that lets the roots fix their own nitrogen. Keep it cool and out of the sun; heat kills it.

Store seed and inputs dry, off the floor, away from food, water and children, and keep every label and receipt.

In the two to three weeks before you sow — finishing just before you plant — loosen the soil to about 15–20 cm (a spade's depth) and break it to a fine, crumbly tilth, especially the top few centimetres where the pegs will enter.

Clear out roots, stones and hard clods — each one blocks a peg and stops a pod forming.

Level the surface so water soaks in evenly and doesn't pool; groundnut hates a waterlogged pod zone.

On a slope, work across the slope, and make ridges or basins to catch the rain if your soil dries fast.

Aim for soil so loose you can push your fingers straight in — that is exactly what the pegs will need to do.

Use only well-rotted manure or compost — dark, crumbly, no strong smell. Groundnut needs little feeding, so a modest amount is plenty.

Spread it evenly and work it into the topsoil 1–2 weeks before planting, so it settles in and keeps the soil open.

Go easy: too much manure — or any heavy nitrogen — grows big leafy bushes with few pods. The plant makes its own nitrogen.

On land that hasn't grown groundnut lately, coat the shelled kernels with Rhizobium inoculant just before sowing: moisten the seed lightly, dust on the inoculant so it sticks, and plant the same day, in the shade — sun kills the bacteria.

Sow into warm, moist soil, when a planting rain has wet the ground to a spade's depth.

Open your rows about a forearm apart (≈45 cm) and drop one kernel every four fingers' width (≈7.5–10 cm) along the row. Groundnut is planted dense on purpose — a thick stand shades out weeds and escapes rosette.

Plant each kernel as deep as two finger-joints (5–7 cm) — a little deeper in dry, sandy soil, shallower in heavier soil.

Band the P/K basal in the row beside and just below the seed, never touching it — fertiliser against the kernel burns it.

Cover and firm the soil gently, and handle every kernel softly — a bruised seed rots instead of growing.

Walk the crop twice a week, following a big W across the field so you cover the corners and the middle, not just the edge by the path.

Look for rosette: plants that are stunted and bushy, with small, crinkled, yellow or mottled (mosaic) leaves — often in patches that spread outward.

Pull out and bury or burn any rosette plants the moment you see them — they cannot recover and they feed the aphids that infect the rest.

Turn a few leaves over and look for aphids — tiny soft green or black insects clustered on the growing tips and leaf undersides. They are the carriers of rosette.

Count the gaps — stations where nothing came up — so you know whether to gap-fill in the next few days.

If aphids are building up or rosette is spreading → act now: control the aphids early and keep the stand dense. Open the rosette and aphid guides.

Within about two weeks of sowing, walk the rows and find the gaps where nothing came up.

Re-sow a fresh kernel — inoculated, on new land — into each gap while the soil is still moist and the rest of the crop is only a few days ahead.

Sow at the same depth as before, two finger-joints (5–7 cm), and firm the soil over it.

Fill sooner rather than later: a seedling that starts two weeks behind never fully catches up, but it still helps close the gap against aphids.

If you have irrigation, keep the topsoil moist but never waterlogged until the crop is up and established — groundnut roots rot in standing water.

Water every 5–7 days, more often on sandy soil and in heat.

Check with a finger: water when the top few centimetres are dry.

Once the stand is up and growing, ease back — the young crop needs far less water than it will at flowering.

Twice a week, walk the W and check plants at several stops across the field.

Look on the lower, older leaves for leaf spot — small dark brown or black spots, sometimes ringed with yellow. It starts low and climbs, and heavy spotting strips the leaves early.

Keep watching for rosette — stunted, bushy, yellow or mottled plants — and pull out any you find.

Check the growing tips for thrips and aphids — tiny insects that scar the young leaves and carry virus.

Note where problems are worst so you can act. If leaf spot is climbing up the plants or rosette is appearing → act: open the matching guide.

Weed by about 3–4 weeks after sowing, before the weeds get bigger than the crop and before the first flowers open.

Hoe shallow, or hand-pull close to the plants — deep hoeing cuts the groundnut's own roots and nitrogen nodules.

Get the field fully clean now: this is your main weeding, because after pegging you can only hand-pull gently.

Do not ridge or throw soil over the crowns. Groundnut flowers and pegs at the base of the plant — burying it smothers the pods before they can form.

Leave the pulled weeds lying between the rows as a light mulch to hold moisture.

If irrigating, water every 7–12 days through this stage, depending on heat and soil.

Keep the soil evenly moist, but let the surface breathe between waterings — groundnut dislikes constant wet feet.

Don't let the crop wilt hard in the run-up to flowering; the number of flowers now sets the number of pods to come.

Apply at early flowering — when the first yellow flowers are opening low on the plants (around 4–6 weeks after sowing) — so the calcium is in place as the pegs go down.

Broadcast 200–500 kg per hectare of gypsum (calcium sulphate) in a band over the rows, like sprinkling ash along the plants, so it lands in the top few centimetres where the pegs enter.

Aim the gypsum over the plant zone, not into the bare middle between rows — the pods form under and beside the plant.

Keep the pod zone moist after applying, so the calcium is available as the pods set.

If you truly cannot get gypsum, well-crushed lime worked into the topsoil before flowering supplies some calcium — but plan ahead and get gypsum, it is the proven fix.

Twice a week, check the leaves across the field, paying attention to the lower and middle leaves.

Leaf spot: small dark brown-to-black spots, often ringed with yellow, spreading up from the older leaves; bad attacks make leaves yellow and drop.

Rust: reddish-brown, powdery pustules on the underside of the leaves that rub off orange on your finger.

Watch that the crop stays green and leafy right through pegging — early leaf loss now directly shrinks the nuts.

If leaf spot or rust is climbing up the plants → act: open the leaf spot / rust guide and protect the canopy.

Walk the rows and hand-pull the weeds you can reach, close to the plants.

Pull gently and straight up, so you don't tear out the pegs that are entering the soil.

Throw no soil over the crowns and do not hoe deep — a broken peg is a lost pod.

Leave the pulled weeds lying between the rows as mulch to hold moisture in the pod zone.

Keep the soil evenly moist right through flowering and pegging — never let the pod zone bake into a hard crust.

Water every 5–7 days, more often in heat, so the pegs can push into soft, damp soil and set pods.

Don't let the crop wilt during pegging — a dry spell here cuts pod number more than at almost any other time.

Moist soil also carries the calcium from your gypsum down into the forming pods.

Walk the field about once a week (every 5–7 days) and look for wilting or dying patches, and for termite runways — thin soil tunnels up the stems — which warn of pods being bored below.

Lift a few plants from different spots and check the pods for holes, tunnelling or empty bored shells (termites), and for any mould or dark staining.

Also look over the leaves: leaf spot — small dark brown-to-black spots, often ringed with yellow — can still strip the canopy this late, and every green leaf you keep helps fill the pods.

Feel whether the crop is drying, and check maturity (see the maturity check) so you can plan lifting — over-mature pods snap off and stay in the soil.

Keep the soil from drying out hard — end-season drought is a main driver of aflatoxin.

If termites are tunnelling the pods or leaf spot is stripping the canopy → act: open the matching guide, and if the damage is spreading, lift as soon as the pods read mature rather than wait.

Keep the soil evenly moist through pod-fill, watering every 7–10 days while the crop is still green and filling.

Never let the crop dry-stress late — a drought right before harvest is the single biggest trigger of aflatoxin in the pods.

As the crop reaches maturity (leaves yellowing, pods hard inside), ease off gently so the crop and pods can dry down for lifting — but don't slam it from wet to bone-dry.

From about 95 days after sowing (for a Spanish/bunch type), lift 2–3 whole plants from different parts of the field.

Crack open several of the biggest pods and look inside the shell: a mature pod has a hard shell with dark brown to blackish veined patterning on the inside wall.

Check the kernels: a mature nut fills the shell and the papery skin has its full colour for your variety, not white and watery.

When most of the big pods read mature like this, the crop is ready — plan to lift within a few days.

If the pods are still pale and soft inside → wait and check again in about a week; but don't wait for the tops to die right back, or over-mature pods will break off in the soil.

First loosen the soil under the rows with a fork or hoe, and lever gently so the roots let go and the pods come up with the plant instead of snapping off underground.

Pull whole plants, shake off the loose soil, and check that the pods are still attached.

Lay the plants in windrows — long rows with the pods facing up — off the wet ground, so air moves through and the pods dry evenly.

Cure them like this in the air for a few days, until the pods are drying and the plants are wilting; this fast start is your biggest aflatoxin defence.

Lift in dry weather if you can, and never leave lifted plants in a damp heap — that is exactly how mould and aflatoxin begin.

Dry the pods on a clean raised surface, mat or tarpaulin — never on bare soil and never in a damp heap. Bare ground pushes moisture and mould straight back into the pods.

Turn the pods so they dry evenly, and cover them if rain threatens.

Dry until the nuts are hard: the kernels rattle in the shell and a kernel snaps rather than bends (about 8–10% moisture).

Shell gently once fully dry — bruising cracks the skins and lets mould in.

Sort out every shrivelled, discoloured, insect-damaged or mouldy kernel — these are the ones that carry aflatoxin. When in doubt, throw it out; never eat or sell the mouldy ones.

Store the clean, dry kernels (or unshelled pods) in clean sealed bags, off the ground, in a cool, dry, airy place, and check now and then for damp, mould or bruchids (small beetles boring the kernels).

If the nuts still bend instead of snapping → they are too wet to store: dry them more before bagging, or they will mould in storage.