Organic waste from either households or gardening can be processed and transformed into soil amendments. This can be a viable option for large cities where a great amount of organic waste is produced and soils are often severely degraded and need to be ameliorated. Therefore is necessary to evaluate how different types of organic amendments  perform in particular soils.

The aim of this study was to evaluate of three organic amendments on 2 different types of soils by growing of barley (Hordeum vulgare) in a pot experiment in the greenhouse. One soil was a sandy loam with medium nutrient contents taken from a Park of Mexico City (vitric Regosol), while the other is a clay loam, with large contents of soluble salts sampled at former lake Texcoco (gleyic-mollic Solonchak). The evaluated amendments were three: a) compost produced with organic waste from Mexico City (CCM), b) compost produced with gardening residues (CUNAM) and c) biochar produced with gardening residues (BIO). Each amendment was applied in 2 doses and compered with a control treatment, without any amendment. Plants were cut down twice. The response variables were plant height, plant biomass production, and plant survival.

Highest plants grew on Regosols amended with either CCM in a medium dose (25 % CCM, 75% Regosol % V/V) or BIO at a medium dose (10% BIO, 90% Regosol % V/V), in Solonchak highest plants grew on CCM in a medium dose (25 % CCM, 75 % Solonchak % V/V). The first cut showed no differences in biomass between the different amendments. The second cut showed largest biomass production when both kinds of compost (CUNAM and CCM) were applied to both kind of soils, at the highest dose (50% compost, 50% soil % V/V). Finally, the largest plant survival was registered at the first cut in both soils amended with CUNAM at the both doses and BIO at highest dose(20 % BIO, 80 % soil % V/V).