What is urban tree soil made of?

Urban tree soil is mostly medium to coarse silica sand carrying a small amount of well-rotted organic matter, around 4 to 5% by weight in the original Dutch specification. The sand is narrow-graded deliberately, because grains of a similar size leave pore spaces that survive compaction. Some versions carry a few per cent clay too, though most UK blends are sand and green compost only.

Is urban tree soil the same as Amsterdam tree sand?

Urban tree soil and Amsterdam tree sand are the same material under different names, and it also sells as Dutch tree sand or structural tree sand. The name comes from Amsterdam, where the approach was worked out from the 1970s onwards to stop street trees dying in paved ground. Blends differ between suppliers, so check the specification, not the name on the bag.

How much urban tree soil do I need for one tree?

Urban tree soil is ordered against the tree's mature canopy rather than the size of the pit, at 0.6 cubic metres per square metre of crown. A small tree with a 3 to 5 metre canopy needs roughly 5 cubic metres, about seven 700 litre bags. A large tree wants nearer 30, which is why street schemes run continuous trenches rather than isolated pits.

Can I use urban tree soil for a tree in my garden?

Urban tree soil is the wrong choice for a tree going into open garden ground, because the problem it solves does not exist there. A tree in a lawn or border does better with its own soil loosened, improved and put back, so roots run out into the garden instead of circling in a sandy box. Our topsoil range is where that job is served.

Does urban tree soil need compacting?

Urban tree soil is meant to be compacted, and that is the entire reason it exists. It goes in as layers of roughly 400 to 500mm, compacted as it is placed rather than tipped loose. The target density stays well short of what a sub-base gets, because the pore space between grains is what keeps roots alive.

Will my council accept urban tree soil in a tree pit?

Urban tree soil is accepted by some UK highway authorities and specifically excluded by others, so the answer depends on whose specification the scheme is built to. Leeds City Council, for one, refuses sand-based tree soils on adopted street tree schemes and asks for soil cell systems instead, on the grounds that a soil compacted that firmly, carrying that little organic matter, is not somewhere roots thrive. If the pit will be adopted, read the authority's guidance before ordering.

Urban Tree Soil: Amsterdam Tree Sand for Tree Pits

Planting trees in urban areas is an important part of city life today. As with all plants, trees absorb carbon dioxide and produce oxygen making our towns and cities safer, cleaner and healthier places to live. Urban Tree Soil, also known as Amsterdam Tree Sand, is the generic term used for a sand based structural growing media used for planting semi-mature trees in paved urban environments developed by Dutch universities over thirty years ago.

The ideal behind Urban Tree Soil is to create a growing medium that allows strong root growth and development whilst also preventing damage to roadways and pavements by mitigating subsidence issues and resisting compaction in highly trafficked vehicle and pedestrian environments.

Urban Tree Soil is created by blending a selection of specifically graded silica sand particles (which create sufficient pore space in the growing media allowing oxygen and moisture to permeate the root zone whilst also allowing strong root development) with the addition of matured quality assured organic material providing the essential nutrients required to facilitate good growth.

Benefits of Urban Tree Soil