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Lawn lime for moss

Updated: October 2026

The neighbour said the moss means the soil is sour, and a bag of limestone is the cure. Lawn lime for moss has to take that story apart. Lime does not kill moss. It is only worth discussing after a fair pH test shows the soil is too acid for the grass you want. This page is from Peter F., the DIY & tools editor, on 21 October 2026. He used the Royal Horticultural Society moss and lime pages, plus the seven amazon.co.uk listings on the [lawn lime comparison](/hub/fertiliser-soil-and-bark-mulch/lawn-lime). A qualifying Amazon purchase can earn us a commission at no extra cost to you. None of those seven listings is a mosskiller.

The neighbour said the moss means the soil is sour, and a bag of limestone is the cure. Lawn lime for moss has to take that story apart. Lime does not kill moss.

Our top picks

Westland Westland Lime Soil Conditioner (pack of 2)

Best overall

Westland Westland Lime Soil Conditioner (pack of 2)
8.2/10about £19.98
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OLDCASTLE LAWN & GARDEN Jolly Gardner Fast Acting Lime

Alternative

OLDCASTLE LAWN & GARDEN Jolly Gardner Fast Acting Lime
4.6/10about £123.16
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MURIEL BARGAINS Levington Garden Lime 3.5 kg

Best value

MURIEL BARGAINS Levington Garden Lime 3.5 kg
4.0/10about £11.49
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On this page
  1. 1.Moss in a lawn is not a lime deficiency
  2. 2.Remove the moss before you talk about lime
  3. 3.Lime only if the pH test says the soil is acid
  4. 4.When to leave the moss

Moss in a lawn is not a lime deficiency

The RHS lists weak or patchy grass, wear, compaction, damp or waterlogged soil, and acidic soil as causes. Acid is one item on that list, not the heading. Shade or a lawn that squelches in January will grow moss on soil that already sits near pH 6.5. One listing in this set claims less moss. Another claims protection from moss and bare spots caused by low pH. Those are listing claims, and this comparison has no evidence block for either. If you later buy carbonate for a low reading, take the integrity check to best lawn lime. Iron sulphate is not lime, and it is not a moss killer unless it sits in an HSE-approved mosskiller with its own rate.

Remove the moss before you talk about lime

Scarify in October or early November while the grass is still growing. Work a spring-tined rake in two directions and take the debris away, or hire a machine if the lawn is too large to rake in an afternoon. Lime has to reach soil. A thatch mat holds granules on top, which is one reason UK reviews of a Westland twin pack mention granules still sitting after heavy rain. If you do lime later, the wait before feed is on how to apply lawn lime. After the rake, use shade-tolerant seed, more light, aeration, and a higher cut. Those steps still matter at moderate pH.
Westland Westland Lime Soil Conditioner (pack of 2)

Testsieger

Westland Westland Lime Soil Conditioner (pack of 2)
8.2/10about £19.98
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Lime only if the pH test says the soil is acid

Test outside the three months after lime, fertiliser, or manure. The RHS treats about pH 6.5 as the general-purpose figure, says you usually add nothing at pH 6.1–7.0, and says not to lime at 7.0 or higher. Fine bents and fescues prefer more acid conditions than a ryegrass family lawn. Which? puts fine grasses around pH 5.5. Lawnsmith uses about 5.5–7. A fine lawn near 5.5 is not an automatic limestone job. Which? published 60 g of ground chalk or limestone per square metre for very acid soil. Lawnsmith's guide is 100 g to move about 0.5 pH, and only below pH 5. Those figures are not the Westland FAQ of 10 g and not Levington's table. If the test is low, use the rate on the bag you hold, after you have raked. If the pH is already around 6.5, do not buy. The other direction is lawn lime or sulphur.

When to leave the moss

A squelchy hollow will grow moss after every rake until the water can leave. Call someone about drainage before you open another sack. Deep shade is where grass may never win: raise the canopy, or keep the moss. Ground limestone will not turn the lawn green this week. If a fair test is still low after the rake, spread that bag's rate and stop.

Common questions

Does garden lime kill moss?
No. Lime changes soil pH when the soil is acid. It does not remove the moss you can see. The RHS removal method is scarifying in October or early November, then dealing with shade, compaction and drainage. A listing claim about less moss is not a kill rate.
Why is there moss if I already limed?
Because acid soil was only one possible cause, or because the pH was never low. Shade, wear, compaction and waterlogging grow moss on soil that already sits near 6.5. A test inside three months of the last bag can also mislead, so you may be reading noise rather than a new deficiency.
Should I scarify before I lime?
Yes, if you are going to lime at all. Granules have to reach soil, and thatch holds them on top. Rake in October or early November, take the debris away, then decide from a fair pH test. Do not lime first in the hope the moss will drop out.
What if the lawn is shady or squelchy and the pH is fine?
Do not buy lime. Prune, raise the cut, aerate, or call someone about drainage. The RHS allows you to keep moss where grass will not win. A moderate pH plus shade is not a limestone job.
Will lime turn the lawn green this week?
No. Ground limestone can take months to show. A greener week is not proof the moss needed lime, and this comparison will not claim a bag greens turf in days. If you wanted a quick colour change, you are shopping for a different product.
Is iron sulphate the same as lime?
No. Lime is calcium carbonate for pH. Iron sulphate is a different chemical. It is not a moss killer unless it is in an HSE-approved mosskiller with its own rate, and that product is not in this category. Do not swap the two on the shed shelf.
Do fine grasses want a lower pH than a family ryegrass lawn?
Yes, in direction. Fine bents and fescues prefer slightly more acid conditions; a ryegrass family lawn sits nearer the RHS general-purpose figure of about 6.5. Which? and Lawnsmith agree on that direction, not on one cutoff. A fine lawn near 5.5 is not an automatic lime job.

Related pages

Lawn lime buying guide

Lawn lime

Best lawn lime: seller, weight and a UK review file

How to apply lawn lime with only that bag's own rate

Lawn lime or sulphur: when to raise pH or leave it

Sources

Public UK and maker sources from the research digest, used for this page in October 2026. Prices, stars and review counts are from the seven amazon.co.uk listings captured on 19 October 2026. A moss line is a listing claim. A maker's pet line applies to that garden lime, not to hydrated lime or to every bag. This is not a laboratory test.

  1. RHS, lime and liming (retrieved 19 October 2026)
  2. RHS, soil pH and testing (retrieved 19 October 2026)
  3. RHS, moss on lawns (retrieved 19 October 2026)
  4. RHS, acidifying soil (retrieved 19 October 2026)
  5. Westland Garden Lime (retrieved 19 October 2026)
  6. Levington Lime (retrieved 19 October 2026)
  7. Fertilisers Regulations 1991 (retrieved 19 October 2026)
  8. CAFRE, the value of lime (retrieved 19 October 2026)