Definition of humus in US English:



  • The organic component of soil, formed by the decomposition of leaves and other plant material by soil microorganisms.

    • ‘Cabbages tolerate heavier soils well, so long as there is enough humus and fertiliser, as they are heavy feeders.’
    • ‘Incidentally, soil rich in organic humus will hold more water longer and be more drought-resistant.’
    • ‘The end point of decomposition is a largely inert organic material called humus.’
    • ‘At first, layer grass clippings with a dash of leaves and twigs to create a concoction that turns into humus, the best plant food.’
    • ‘In addition, continue to put out organic humus as you plant.’
    • ‘In sandy soils, humus acts like a sponge to catch and hold moisture.’
    • ‘There is a smell of humus and dirt and leaves and rain and nothing else.’
    • ‘But (as some might reply) we can add peat or humus to the soil as we till.’
    • ‘An all-purpose potting mix has composted bark, peat moss or peat humus added to loamy soil.’
    • ‘Mature compost is a complex organic material that has been transformed into stable humus by microorganisms.’
    • ‘Their soil must contain sufficient humus and be rich in calcium, but the idea that cyclamens need a lot of moisture is a misconception.’
    • ‘Since these species originated in a wooded habitat, they require a loose soil with sufficient humus.’
    • ‘Soil should contain a good mix of sand, clay, and humus.’
    • ‘If it's sandy or stiff with clay, dig in humus to improve water retention and aeration.’
    • ‘The final product, humus or compost, looks and feels like fertile garden soil.’
    • ‘Lack of biological insect control necessitates using more pesticides, as lack of humus and plant litter necessitates using more chemical fertilizers.’
    • ‘If grown in plenty of humus and leaf mould, rhododendron roots almost peel off the ground.’
    • ‘What's left is nutrient-rich organic matter, or humus, which can be used as a soil amendment.’
    • ‘Don't spurn organic fertilizers that are low in nutrients, because they're rich in organic matter that turns to valuable humus in the soil.’
    • ‘The mulch keeps the soil moist, and as the lower layers decompose, they enrich the soil with humus.’
    earth, loam, sod, ground, dirt, clay, turf, topsoil, mould, marl, dust
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Late 18th century: from Latin, ‘soil’.