Flowering hedges
Who says hedges have to be clipped and green? Instead, they can be freestyle and filled with flowers, as JENNIFER STACKHOUSE reveals
We live surrounded by hedges on our property in northern Tasmania. We have a huge clipped cypress hedge on one side, while the hedges that run around the other boundaries are mixed, informal plantings of trees and shrubs. These are mainly leafy plants, such as variegated pittosporums and birch trees, intermingled with Viburnum tinus, a cool-climate shrub massed with flowers in winter and spring.
We also have hedges dividing internal areas throughout the garden. Traditional box hedging forms a neat border near the house, and there are clipped sasanqua camellias, correas and, my favourite, a white banksia rose (Rosa banksiae). This is so old, it has become self-supporting, having long outgrown the fence and arch it was trained on originally.
All year round, our hedges provide a safe haven for birds, particularly small natives such as blue wrens, spinebills and crescent honeyeaters. When the hedges are in flower, they also attract insects and, in the case of the banksia rose, its wonderful scent of violets perfumes the air for weeks.
DECIDING WHAT TO PLANT
Any shrubby plant with dense growth can be grown as a hedge. As in my garden, flowering hedges can either be clipped with geometric precision or allowed to grow in a loose way that reflects the natural size and shape of the shrub. When hedges are grown in this way, with minimal pruning, they are referred to as ‘informal’, while those that are clipped and shaped regularly are called ‘formal’ hedges.
The key to a successful flowering hedge is when it is pruned. If this is done at the wrong time, the flowers may be sacrificed. To enjoy the flowers and have the benefit of the hedge as a garden backdrop or privacy screen, clip the hedge after flowering. For example, the sasanqua camellia hedge in my cool-climate garden is pruned in spring or early summer, which is after its autumn to early-winter flower display but before the new buds form. In warm zones, though, it could be pruned in late winter.
Choose a flowering plant you like the look of, but keep in mind the space you have for the hedge and how well the plant responds to pruning. Also, decide how much pruning you want to do. Abelia, for example, can be grown as a clipped hedge in a small space or allowed to grow into its naturally arching form for an informal effect.
The best choice for a hedge is a dense, leafy shrub (or shrubby climber) that will tolerate close planting and handle pruning. See ‘Top 10 choices for a flowering hedge’ on page 18 and ‘12 more to consider’ on page 20 for lists of shrubs that give lots of bang for your buck. These all produce long-flowering and strong, disease-free growth that is suitable for pruning or can be left to grow into its natural shape.
PLANT A PERFECT FLOWERING HEDGE
A flowering hedge is planted much like any green hedge. Space plants about a metre apart – or at roughly half their width – so they grow to form a compact screen. Closer planting gives a faster, denser hedge but may require more water, fertiliser and pruning to keep it strong and in shape.
If you intend to grow an informal hedge, allow space around the plants for them to grow and spread. If you plan on keeping the hedge neatly clipped to a specific height and width, make sure there’s easy access to all sides for pruning.
Hedging plants need regular watering to become established, and flowering hedges also benefit from additional water as they come into bud and flower. Installing a dripper or micro-irrigation system at planting makes it easy to keep up the water.
Most flowering hedges need an annual application of fertiliser, usually in spring, and vigorous growers benefit from additional feeds in summer.
If you're growing a native hedge, be sure to use a plant food specially formulated for natives.