Landscaping Topsoil

How deep should landscaping topsoil be?

Landscaping topsoil needs 100mm under new turf or grass seed, and 150mm in a planted bed. Less than about 75mm and the roots reach whatever is underneath before the plants have established.

What is the difference between topsoil and compost?

Topsoil is mineral soil, roughly 90% sand, silt and clay with a few per cent organic matter. Compost is that organic matter alone, so it improves soil beautifully and replaces it badly: plant into pure compost and the level drops as it rots.

How much does an 850kg bag of landscaping topsoil cover?

An 850kg bag of landscaping topsoil is around 0.55 cubic metres, covering roughly 5.5 square metres at 100mm depth or 3.5 square metres at 150mm.

Can you grow vegetables in landscaping topsoil?

Landscaping topsoil is the wrong soil for a vegetable bed: it carries 5.9% organic matter where a productive bed wants more, and it sits slightly alkaline at pH 7.8. The bigger problem is stone size, because it is screened to 20mm and carrots and parsnips fork on anything they hit. Our vegetable topsoil is screened to 10mm specifically for edible beds and allotments.

Is landscaping topsoil suitable for rhododendrons and other acid-loving plants?

Landscaping topsoil is too alkaline for rhododendrons, camellias, pieris and blueberries, which want pH 5 to 5.5 against this soil's typical pH of just under 8. Our lime-free ericaceous topsoil runs pH 4 to 6.

Will grass grow through landscaping topsoil?

Grass grows through a dressing of landscaping topsoil up to about 10mm deep and dies under anything much thicker. To level a lawn, spread 10mm, let it come through, then repeat next season.