The Ultimate Guide to a Naturalistic Gravel Garden

The New Sustainable Choice

Let’s face it! Gardening this summer was hardly a labour of love, was it? Hosepipe bans meant having to lug watering cans up and down the borders every day. Waking up every morning to the prosect of shrivelled and desiccated plants, if you missed a day’s watering.

So, I think it’s time we stopped fighting climate change and started adapting our gardens to the changing weather conditions. But it’s not all bad news. A whole raft of exotic plants, not reliably hardy a few decades ago, are now able to withstand our warmer winters and drier summers.

London’s Royal Parks, the charity that manages the capital’s eight royal parks, has made plans to transform their gardens, using climate resilient, drought tolerant plants to create displays that will be hardy and pollinator friendly. The launch of the Queen Elizabith II garden in Regents Park this April, has seen the first of many such transformations. The emphasis is on sustainability and biodiversity.

With the need for regular weeding and watering reduced, and allowing self-seeders to spread freely, our gardens end up being much easier to take care of.

But, along with persistent heat waves, come warmer, wetter winters, so soil preparation is key.

Make Your plan

Whether you are transforming a small patch of ground or an extensive border, a successful gravel garden needs a sunny position. Your choice of plants will depend, in part, on your local climate so do your homework. Most on-line nurseries will rate a plant’s hardiness in their description. Consider what type of soil you have; is it heavy clay or light sandy loam? The type of soil that you have will determine which plants will thrive. A simple soil pH testing kit from your local garden centre will tell you whether you have acid, alkaline or neutral soil.

It’s all in the Soil

First, clear your area. Weed thoroughly. Using a half-moon spade, cut your border into shape, removing any turf. A sharp edge will make the border look smarter. A free draining soil is vital. If you have heavy clay soil, ideally dig over your border to about 15cms deep, removing any solid clumps. Then spread a 20cm layer of 50/50 mix grit and topsoil; no need to dig it in, the worms will do that for you in time. This will improve drainage and hopefully stop your plants from succumbing to prolonged spells of cold and wet in the winter.

If you have free draining, sandy soil then you’re laughing, as this mimics the natural habitat of drought tolerant plants. Do not add fertiliser. Forcing rapid growth with nutrients makes plants soft and leggy rather than sturdy and compact. Unlike other forms of planting, do not lay a weed suppressing membrane; you want your plants to be able to self-seed freely into the soil.

Right Plant Right Place

When choosing plants, consider the overall appearance. A mixture of Mediterranea herbs, structural perennials, ornamental grasses and self-seeders will provide layers of textural contrast and extend the seasons of interest.

Mediterranean herbs such as thyme, oregano and marjoram will form dense aromatic carpets. Silver leaved shrubs, such as santolina and artemisia, and perennial ground cover like stachys Byzantina or Lamb’s Ears, are drought tolerant and thrive in full sun. Fragrant English Lavender, such as Hidcote or Munstead, is best for sunny gravel beds, loved by bees and other pollinating insects.

Ornamental grasses give movement and rhythm if planted in swathes. Tall miscanthus, panicum and calamagrostis, with medium stipa tenuissima, pennisetum, deschampsia, hakonechloa, look amazing in winter, providing safe haven for wildlife. Evergreen carex keep their colour and foliage all year.

Self-seeders such as love-in-a-mist, Californian poppies, slender dianthus carthusianorum, verbena bonariensis, ammi, will mingle in the gaps. Sow them in the first year and allow them to go to seed, and they will spread themselves around naturalistically.

Plant with precision

Before planting, saturate your root ball. Add more grit to the planting hole and ensure the crown is level with the soil. Water well initially, and at regular intervals in the first year, to allow the roots to establish. After that, your plants should not need watering, except during exceptionally long periods of drought.

Sow your annuals thinly, direct onto the soil where you want them to grow. After that, it’ll be up to them!

Once you’ve completed your planting, it’s time to add the gravel. Select your stones from a good nursery or landscape merchant; a 10-to-15cm layer of gravel would be my choice. As well as being ornamental, this layer of gravel will act as a weed suppressant and provide winter protection. Carefully spread it around the plants, taking care not to smother their crowns.

Keep it Looking Good

Once your borders have established, regular maintenance is key. At the end of winter, cut back and remove all last year’s top growth, adding it to your compost heap.

Regularly clear any debris, such as fallen leaves, grass clippings, twigs, so that they do not breakdown into the soil and encourage weeds. Pull out stray weeds, including their roots, by hand. Remove spent self-seeders, being careful not to pull up new seedlings. Brush away any worm casts that come to the surface of the gravel.

Every few months, rake and level the gravel to reestablish shifted stones, smooth out thinned patches and keep the border neat. Add fresh gravel every 2 to 4 years to maintain the thick layer. You may need to top up the gravel here and there in the interim.

Keep your border edges well defined, using barriers such as metal edging, timber or stone, to prevent the gravel from spilling onto lawns and paths.

More from Caroline: Shrubs That Survive and Thrive and How to Design a Stunning Front Garden.