Action Synopsis: Soil Fertility About Actions

Amend the soil with composts not otherwise specified

How is the evidence assessed?
  • Effectiveness
  • Certainty
  • Harms

Study locations

Key messages

One controlled, randomized, replicated trial in Italy found that applying a high rate of compost increased soil organic matter levels, microbial biomass and fruit yield.



About key messages

Key messages provide a descriptive index to studies we have found that test this intervention.

Studies are not directly comparable or of equal value. When making decisions based on this evidence, you should consider factors such as study size, study design, reported metrics and relevance of the study to your situation, rather than simply counting the number of studies that support a particular interpretation.

Supporting evidence from individual studies

  1. A controlled, randomized, replicated experiment in 2001-2009 on silty-clay soil in Italy (Baldi et al. 2010) found 169% more soil organic matter in soil receiving 10 t/ha/year of compost compared to an unfertilized control, after 8 years. Soil receiving 5 t/ha/year of compost applied had 75% more organic matter compared to the control. Mineral fertilizers had no effect on organic matter levels. Soils receiving compost at 10 t/ha/year had higher microbial biomass (12 mg/g soil) and fruit yield (51 kg/tree) compared to the control (6.6 mg/g soil and 43 kg/tree, respectively). Six treatments replicated four times were applied to nectarine Prunus persica trees: (1) unfertilized control, (2) mineral fertilizer including phosphorus (100 kg/ha), potassium (200 kg/ha) and nitrogen (70 kg/ha), (3) cow manure (10 decreasing to 5 t/ha), (4) compost at planting then 5 t/ha/year, (5) compost at 5 t/ha/year, (6) compost at 10 t/ha/year. Soil samples were collected annually in September to 40 cm depth. Nectarine trees were spaced at 5 m between rows and 3.8 m between trees. Compost and manure were measured in tonnes of dry weight.

    Study and other actions tested
Please cite as:

Key, G., Whitfield, M., Dicks, L.V., Sutherland, W.J. & Bardgett, R.D. (2020) Enhancing Soil Fertility. Pages 613-634 in: W.J. Sutherland, L.V. Dicks, S.O. Petrovan & R.K. Smith (eds) What Works in Conservation 2020. Open Book Publishers, Cambridge, UK.


Where has this evidence come from?

List of journals searched by synopsis

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Soil Fertility

This Action forms part of the Action Synopsis:

Soil Fertility
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