Water in the garden offers a wonderful element of movement and sound. It can be hard a stream look good, and sometimes the challenge is even greater. When the water is a man-made affair, more utilitarian than anything else, water and uneven edges often equals scruffy!
Here a man-made stream running along the front of a native shelterbelt has long looked a bit of a mess – but while the trees established and the owners got the house and the rest of the garden under control it was to a priority. It was an eyesore.
We needed to tidy up the bank, to integrate it into the garden and to clothe it with sympathetic plants.
The Design Decision
Our decision was to make it a design feature. To make it complement the native shelter planted behind, and to get a sweep of drama from using grassses, and the added element of life and movement that they bring.
Planting would be key – the bank was also hot and dry in summer, despite the waterway, and only drought-resistant plants would survive here. Native grasses would complement the existing planting and a long stretch would have marvellous movement in the wind. Breaking this up and adding contrast, mounds of hebe, glossy coprosmas and pachystegia, spikes of the lancewood and bold flaxes were included.
Using a deep gravel mulch increases reduces soil moisture loss while maintaining good drainage – the key to success with many native plants. Gravel is also a local material; millennia ago this area was riverbed. The stumps of gum trees lined the bank – these were left, providing interest and, potentially, a home for scrambling plants such as Parsonia heterophylla, the native jasmine, or clematis once some shade can be provided.
Preparing and Planning
The hard work was to spend a summer clearing the bank of weeds – a must for long-term low maintenance. A collection of native grasses, flaxes, hebes, Marlborough rock daisies and lancewoods was grown on in a spare vegetable plot. The idea was the grasses, at least, would be able to be divided, reducing the cost of planting such a large area.
The bank of the waterway was edged with treated timber to provide a stable environment when soil and the gravel mulch were added. (On a steep or difficult site and when building a retianing-type wall over 90cm (3ft) always get professional advice and help.) This also prevented weeds seeding into the bank and establishing. This was then tied back using takes and wire and levelled, filling with topsoil.
A weed-cloth barrier was laid over this (double thickness). The plants were planted through the mat. Extra soil was added around them if the planting area looked a bit dire.
Grasses add movement in the garden
This project is intended for low banks in private gardens only. High or large banks, and those on very steep and exposed positions will require a professional advice and a professional builder.
Banks and slopes are subject to slumping and you may need a permit before you can begin construction. Check first with your local authority.
||You will Need
- Builder's level
- Stakes, string and tape measure
- Hammer, nails and saw
- Weed cloth
- Retaining timber and stakes
- Gravel. bark or other mulch material
Preparing - the retaining timbers
Fill and then cover with a weed cloth
Step-by-step: Cutting an 'X' for each plant