Fertiliser application

Fertiliser spreading for paddocks and grassland

Fertiliser spreading puts an even dressing of granular fertiliser across grassland to boost growth where the soil is short of nutrients. It’s for grazing and hay fields that have been cropped hard, and for paddocks where a soil test shows something is lacking.

What’s involved

A tractor-mounted spinner spreader throws granules across a set width, and the tractor drives at matched spacings so the whole field gets the same rate. An even spread matters: overlaps scorch and gaps leave pale stripes.

Grassland fertiliser usually supplies nitrogen for growth, often with phosphate, potash or sulphur. Horse paddocks generally need much less nitrogen than dairy or silage fields — lush, sugary grass can be a problem for horses and ponies prone to laminitis.

The right product and rate depend on the field. A soil test for pH, phosphate and potash is the sensible starting point, and on grazing fields a low-nitrogen or no-nitrogen dressing is often all that’s needed.

When to do it

Spring is the main time, once the grass has started to grow and the soil is warming — typically March to April. Hay and silage fields may have a further dressing after cutting. Spreading when the grass can’t use it just wastes fertiliser and risks it washing into watercourses.

Don’t spread on waterlogged, flooded, frozen or snow-covered ground, or when heavy rain is forecast. In Nitrate Vulnerable Zones there are closed periods, running through autumn and winter, when nitrogen fertiliser can’t be spread on grassland — check the current dates on GOV.UK if your land is in an NVZ.

Good to know

Keep horses and livestock off until the granules have been washed in by rain; check the product label for any grazing interval.

Keep fertiliser well clear of ditches, streams and ponds. Spreaders can be set to throw to one side only along a boundary.

Don’t spread nitrogen fertiliser at the same time as lime — leave a gap of a few weeks between them.

If you have laminitis-prone horses or ponies, tell the contractor. A dressing for a dairy field is not the right one for a pony paddock.

Fertiliser application: common questions

When should I fertilise my paddock?

In spring, once the grass has started growing and the soil is warming, usually March to April. Avoid wet, frozen or waterlogged ground. A soil test first tells you what the field actually needs.

How long should horses stay off a field after fertilising?

Until the granules have dissolved and been washed into the soil by rain, and not before any interval on the product label. If there’s no rain, it takes longer.

Do horse paddocks need fertiliser?

Often only a little, and sometimes not at all. Horses do best on grass that isn’t too rich, so paddocks usually need far less nitrogen than dairy or silage fields. A soil test shows whether phosphate, potash or lime is the real shortfall.

When can’t you spread fertiliser?

Not on waterlogged, flooded, frozen or snow-covered ground, and not before heavy rain. If your land is in a Nitrate Vulnerable Zone, there are also closed periods through autumn and winter when nitrogen can’t be spread on grassland; GOV.UK has the current dates.

Often booked alongside

Lime spreading — Lime spread to correct soil pH on grassland or arable.

Overseeding — Repair thin or worn paddocks with fresh seed.

Weed control & spraying — Targeted treatment of docks, nettles, thistles and ragwort.

Harrowing — Break up thatch, spread muck, level the surface.