Lime Requirement Calculator

Calculate how much lime to apply to reach your target soil pH

Work in progress — this calculator is still under development and may not be fully accurate. Use results as a guide only.

Soil pH

From a soil test

6.0–6.5 for most grassland

3.75 t/ha ground limestone equivalent per 0.1 pH unit

Lime material & field

24.71 acres

Application rate

7.50t/ha

Ground limestone7.50 t/ha ground limestone equivalent

A second application of 18.75 t/ha is recommended the following year to fully correct pH. See split application detail below.

pH Shortfall

0.7

pH units

Material needed

75.0

tonnes (year 1)

GL equiv

7.50

t/ha

Est. cost

£2625

at £35/t

Split application recommended

Year 17.50 t/ha — 75.0 t total
Year 218.75 t/ha — 187.5 t total

RB209 recommends splitting applications exceeding 7.5 t/ha GL equivalent to prevent short-term over-liming.

pH correction summary

Current pH5.8
Target pH6.5
Soil typeMedium loam (3.75 t/ha per 0.1 unit)
Lime materialGround limestone (factor 1)
Application rate7.50 t/ha

About lime requirement: Rates based on RB209 soil buffer capacity values. Actual requirements should be confirmed with a soil analysis from a UKAS-accredited laboratory. Lime should be incorporated by cultivation where possible; surface applications take 2–3 years to move through the profile. Do not apply lime within 3 months of slurry or ammonia-based nitrogen fertilisers to avoid N loss.