A really good herbaceous border is a great gardening achievement that requires a combination of (a little) botanical know how, careful planning and a keen eye for design. However, that said, you don't need to be Piet Oudolf to successfully re-design your borders. Here are my top tips for overhauling planting design.
Don’t be afraid of cutting out large borders to accommodate plants. Traditionally, herbaceous borders were planted in wide beds to accommodate tall plants at the back, medium height plants in the middle and low growing species at the front of the border. A metre or two may seem big in your minds eye but on the ground this isn't going to give you a lot of depth to create drama and add interest. If you've got the space, I wouldn't go much narrower than 3 metres. This sends many people running for the hills at the thought of maintaining such large borders but clever plant selection and mulching can help get around the amount of weeding you’ll have on your hands. No garden is no maintenance and although herbaceous borders are a little more maintenance (deadheading, watering and dividing every few years) than other areas of the garden, you are rewarded in summer with a display that will knock your socks off. After all, isn't it true that there are few extremely rewarding and beautiful things in life that require little effort to attain?
Mix it up: The down side to most herbaceous perennials is their absence in winter. Its for this reason that there has been a shift towards mixed herbaceous borders which incorporate evergreen and deciduous trees and shrubs to create year round structure and interest. Bulbs are great filler plants and a fantastic way to add low maintenance colour and interest to your borders. Nobody grows bulbs for their foliage and growing them amongst other plants is an excellent way to disguise the leaves, especially as they begin to brown and die back.
Stick to a theme:
Choosing plants with complimentary or similar flower colours is a simple way to tie a border together. In the Dukes Garden at Kew, I worked on the blue and white border - unsurprisingly it delivered exactly what it said on the tin beautifully from June - October. Using plants from a similar colour palette can create a sense of peaceful harmony in the garden. The theme may be dictated by the growing conditions or existing planting in this particular area of the garden (for example woodland or Mediterranean style planting). Good horticulture is a core consideration of mine when designing with plants. There are certain plants that just don't work together horticulturally (based on their preference for growing conditions) and bringing them together in the garden may not only be a failure horticulturally - if they do survive, they will probably look just plain weird and out of place together!
Repetition and big groups:
Try to resist the urge of planting your borders like a kid in a candy shop. One of everything will temporarily satisfy the greed to have every plant you fancy squashed into the border but you’ll be left feeling a bit sick at the end of the day when you realise the overall effect has missed the mark. Restrict your plant palette to a shortlist of species that will (a) thrive under the existing growing conditions and (b) tick your boxes in terms of structure, colour and interest. Once you’ve decided on a core selection, plant in large drifts to create greater impact and repeat key players throughout to create a sense of cohesion. Planting in this way ensures you’re border won’t become an eclectic mish mash of disjointed planting that is displeasing to the eye.