How to design a garden of perennials and grasses
This is the most fashionable garden style at the moment — and for once, fashion is right.The garden of perennials and grassesis not a decorative trend: it is a fundamental response to how we can garden today. But behind its free meadow appearance lies a true discipline of composition, one taught by landscape designers likePiet Oudolfand Tom Stuart-Smith. Here is the thinking behind it, and how to achieve it.
Where this style comes from — and why it matters today
The garden of perennials and grasses was born from a movement: theNew Perennial, or "Dutch Wave" (Dutch Wave). It took shape in the early 1980s, around the open days of the Hummelo nursery in the Netherlands, hosted by Piet and Anja Oudolf — alongside figures like the nurseryman Henk Gerritsen or the philosopher Rob Leopold. In Britain, Tom Stuart-Smith, a multiple gold medalist at Chelsea, will extend its spirit. Piet Oudolf will become its global figure — it is his hand that we find behind the High Line in New York or the Lurie Garden in Chicago.
Their revolution hinges on one idea: we no longer choose a plant solely for its flower, but for itsstructureand for the entirety of its life cycle — the shape of its foliage, its silhouette, its inflorescences once faded. A plant must "hold" beforeandafter its flowering.
Why does this matter today? Because this type of garden answers several questions at once. It is rich in biodiversity and nourishes pollinators. Once established, it withstands dry summers well and requires little water and no products. And it offers something beautiful in all seasons — including winter. This is not a passing trend: it is a way of gardening suited to its time.
The logic of composition: structure first
It all starts from Oudolf's idea: the flower is a moment, the structure is permanent. Therefore, we compose with volumes, textures, silhouettes — colour comes later, like an event.
In practical terms, this translates into a question of proportions. Grasses form the framework, the backdrop: they provide movement, rhythm, and the 'body' of the planting throughout the year. Perennials, on the other hand, punctuate this framework with colour and blooms. At Umilys, we often start from a simple working rule: let thegrasses dominate — around 70% of the composition— and reserve the rest, about 30%, for perennials. This is not an absolute rule, but a starting point that avoids the most common mistake: a planting that is too flowery, too heavy, which collapses by the end of summer.
The colour palette: starting from an intention
One does not compose a perennial garden plant by plant. We start from anintention— an atmosphere we want to create. A warm, autumnal palette, played on ochres, purples, and browns? A fresh, silvery, almost graphic palette? Soft, airy pastels? It is this choice that then guides each decision.
And once the palette is chosen, a piece of advice:dare to be generous.A timid perennial garden is a sad garden. This style rewards abundance and boldness — as long as you stay within the palette decided at the start. Generosity, yes; cacophony, no.
The repeating patterns
Here is the least visible, yet most important secret: therepetition. What makes a perennial bed read like a composition — and not like a jumble — is that the same plant, or the same small group, appears in repeated touches throughout the bed. The eye follows this rhythm, and the apparent disorder becomes music.
This is exactly the difference between a successful naturalistic garden and a chaotic flowerbed. The natural is constructed; it is not improvised.
A garden that also lives in winter
This is perhaps the most radical idea of this style:you do not cut everything back in autumn.The dry stems, the faded inflorescences, the silhouettes caught by frost in the low winter light — this is, the garden in winter. Brown is a colour; the dead structure is still beauty., le jardin en hiver. Le brun est une couleur ; la structure morte est encore de la beauté.
So we wait for the end of winter, just before the vegetation restarts, to cut everything back at once. In the meantime, the garden will have inhabited the bad season instead of enduring it.(This is the whole spirit of the garden designed for winter — a theme we also address in full.)
The garden is sown and moves
A garden of perennials and grasses is alive, in the strong sense: it moves. The plants self-seed, some spread, the composition shifts slightly from year to year. This is a quality, not a flaw — it embodies the spirit of the "garden in motion" dear to Gilles Clément: to accompany the living rather than to freeze it.
But this can be managed. Not all species have the same vigour: if left unchecked, the more expansive ones would eventually smother the others. The role of the gardener — and of the landscape architect who designs the bed — is toarbitrate this competition: to encourage here, remove there, divide a clump that is too greedy, allow a spontaneous seedling to settle if it lands well. One does not control the garden; one edits it.
Maintenance: demanding at first, generous afterwards
Let’s be honest, as few articles are: this garden is not "low maintenance". Thefirst two to three years— the time of establishment — require real attention: watering until the roots go down, weeding seriously so that the chosen plants take over before the unwanted ones.
But once this stage is passed, the relationship reverses. The bed returns each year with strength, the plants cover the ground and smother the weeds themselves, watering becomes unnecessary or almost, and maintenance is reduced to the major annual cut at the end of winter and this editing work. It is one of the most generous styles there is — provided that the first seasons have been managed.
Making yours successful: the method
The approach, in summary.Observe the sitefirst: most of these plants want sunlight and well-draining soil.Choose the intentionand the colour palette.Build the framework: grasses as the dominant (~70 %), then perennials (~30 %) in repeated punctuation.Plant densely and in repeated patterns, so that the bed holds together and is readable.Maintain for the first two or three years— watering, weeding. Then, each year,cut at the end of winter and edit: that's all, and it's a lot.
Frequently asked questions
What is a perennial and grass garden?
It is a garden inspired by the movementNew Perennial(or 'Dutch wave'), born around Piet Oudolf. It combines perennials and grasses chosen for both their structure and their flowers, planted densely and in repeated patterns, for a natural yet controlled effect, beautiful in all seasons.
Is this type of garden maintenance-free?
No. The first two to three years require real attention — watering and weeding, during the establishment period. After that, it becomes one of the most low-maintenance styles: it returns on its own each year, suppresses weeds, and only requires an annual cut at the end of winter.
Which plants to choose?
For grasses: miscanthus, calamagrostis, molinia, stipa, pennisetum, sporobolus… For perennials: echinaceas, rudbeckias, asters, yarrow, sages, sanguisorbas, eupatoriums. The right choice mainly depends on your exposure, your soil, and the desired colour palette.
Should everything be cut in autumn?
No, on the contrary. We leave the dry stems and faded inflorescences in place all winter: they provide the structure and beauty of the garden during the bad season. The cutting is done all at once, at the end of winter, just before the restart.
In summary
The garden of perennials and grasses looks open; it is actually composed. It looks easy; it requires attention at the start. But it is also one of the most appropriate for our time: lively, rich in biodiversity, water-efficient, beautiful even in winter. Well designed — the right framework, the right palette, the right patterns — it offers you a garden that keeps renewing itself.