Trowel and error
To succeed in creating plant combinations takes time and experience. A good way to learn is to start off with small groups of plants that work well together and build them up until you have filled your border with several combinations.
Your planting plan
By using your final garden layout as an underlay, trace the areas to be planted and work on the plan to scale (1:50).
Use plant dictionaries and catalogues to establish the eventual sizes of trees and shrubs to help you ascertain planting distances. Buying mature trees and shrubs, while costly, will make this job easier.
Young trees and shrubs need space to grow. Don't be tempted to crowd them together - moving a shrub later may not always be successful.
It’s much better to leave the correct distances between the key plants and fill in the gaps with perennials and annuals.
First decide on your key plants and mark them on your plan using circles that equal the eventual spread of the plant. In a large garden this may be a tree or large shrub, whereas if your garden is small, this could be a Yucca or Cordyline.
Next choose your skeleton planting - that is the evergreen backdrop, which provides screening and shelter, like climbers and shrubs/wall shrubs.
In front of the screening come the decorative plants - architectural specimens with bold foliage like Phormium and Rodgersia for sunny spots and Bergenia and Asarum (wild ginger) for the shade. Contrast all these with soft flowering perennials and at this stage you should consider colour as well as form.
Put all this down on paper and be ruthless and eliminate about half the number you have selected. A common mistake among inexperienced gardeners is to plant too much.
Some plants lend themselves to being planted singly like a specimen tree, grass or bamboo, but when it comes to the fillers, plant in groups or masses, rather than just one of each type, which will look ‘dotty’ and will lack impact. And by planting the groups in odd numbers - even in a small space - a more naturalistic effect will be achieved; the most striking and satisfying visual pleasure comes from the repetition or the massing of one simple element.
Know what you want, and try to express it simply - if you want an herbaceous border, go all out for it and make it as wide as possible. Think too about maintenance and keep to a simple planting scheme that won’t become a burden. Vary the height and overall shapes of your chosen plants and ensure you have a good mix of evergreen and deciduous shrubs in a variety of foliage colours - grey, green, red, variegated - but don’t include too many variegated plants and certainly don’t plant them by side, which will look busy and un-restful on the eye. Add herbaceous perennials and bulbs, and trees too, if room allows.
The range of plant material available today is so large that anyone new to gardening can easily lose their way. Stick to your plan and resist the temptation to buy on impulse, although it is a good idea to earmark a few alternatives in case you can’t get your first choice. Seek out the plants on your list, which may not be flowering at the time of your shopping trip, and be on the look-out for unusual specimens with interesting foliage. It’s not all about flowers - green is a colour too.
Tip: If you don’t have the right conditions for a plant you intend to purchase, then don’t buy it. You can’t fight nature.
Sources of inspiration
To the uninitiated, it can be hard choosing the right plants when the only source of description at your disposal is the garden centre label. A good reference book is essential and you can’t do better than purchasing a copy of the handy pocket-sized RHS Good Plant Guide.
It contains the names of 3,000 plants, all with the RHS Award of Garden Merit (AGM), which means they have been tried and tested by the RHS and are all worthy contenders for any garden, given the right conditions. It also contains a guide, which lists plants for specific purposes - e.g. container plants, variegated shrubs, plants for autumn colour.
Use the online RHS Plant Selector
Another great reference - actually a nursery catalogue - is Notcutts Book of Plants, which lists plants for sale, with prices, and has an extensive index of Plants for a Purpose, including a monthly calendar by colour - very useful. If you don’t have easy access to a Notcutts Garden Centre visit the website www.notcutts.co.uk where you can purchase a copy.