Prevent soil damage during construction projects
Soil aftercare in construction
Structurally-weakened soil tends to settle and self-compact after it's been spread - leading to anaerobism (lack of oxygen) and waterlogging. These are the most common soil-related causes of plant failure on landscaped areas.
Even when the soil isn't compacted, it can take up to three years for the soil structure to stabilise and offer the necessary aeration and drainage for plants to grow properly.
Where a landscape contractor is used, it's common to retain their service for up to five years after installation on a 'defects liability' arrangement. Such a maintenance programme should include monitoring soil conditions to identify unsatisfactory growing conditions.
Amenity grass
Tractor-drawn or self-propelled equipment can be used to verti-drain, slit or spike the turf and topsoil. This will break-up any panning and compaction - improving drainage, aeration and root function.
Other effective treatments include:
- applying fertiliser
- applying herbicide
- top dressing with sand, soil or compost
- over-seeding to improve grass cover
Tree pits and planting beds
For trees and shrubs, it's essential to monitor conditions to identify any problems as early as possible.
Tree pits can act as sumps for draining water - this leads to anaerobic conditions, root rot and can ultimately completely kill the tree. Possible remedies include drying out the soil by opening up the pit or pumping the stagnant water out.
Applying wood mulches to planting beds can cause compaction. You can usually relieve this by spiking the soil with a hand fork between the plants. Where compaction is deeper, or on larger areas, mechanised treatment may be necessary.
You should also include fertiliser application as part of your maintenance programme - particularly for the first few years. Compound, slow-release or controlled-release fertilisers are best for tree and shrub topsoil.
You can also download a code of practice for soil use on construction sites (PDF, 737K).