The plants need to be low maintenance, grow to a suitable size for the garden, suppress weeds from early on and mature relatively quickly. The aim is that for the average two years that someone puts in a new border, there’s some watering and weeding required but thereafter it’s low maintenance and naturally under control.
Structure and form is important – colourful bedding in the summer goes down to nothing in months, so choose a mix of herbaceous shrubs that have year-round interest, leaf, scent and bark. Bedding is easy to add annually.
It’s important to know the final size of the plants and that they will be appropriate to the size of your garden at full height. Volunteers need to be able to prune shrubs whilst standing on the ground, so no Leylandii!
Appropriate speed – plants like clematis Montana won’t cover the fence quickly. In reality it takes two years to get going but then it covers the entire fence for years to come, dominating the area because it’s such a monster to prune. Things need to be mature in three to five years.
Where to plant is also important. Can the lawn be mown around the bed? Is it under trees so nothing will grow nine months of the year? Is there a hedge behind that contractors will need to access?