Designing with Grasses
I love designing with grasses. Grasses bring so much to a garden design, and I will always encourage them into a scheme wherever and whenever I can!
Grasses - or grass like species including sedges and rushes - are a wide ranging group of plants (ecologists would get twitchy at a sedge being called a grass, although interestingly in the landscaping industry they are all grouped in the ‘grass’ nomenclature).
Grasses in a planting borders provide a long season of structure and interest. Species including Stipa, Pennisetum and Eragrostis can create an etherial quality to the garden design when backlit by the setting sun and when they glow in the warmth of the evening or autumnal light. Other grasses are grown less for their flowers and more for their foliage, including Carex varieties, Anemelanthe and Hakonechloa.
Grasses in the summer border can soften the scheme and create a veil and transparency through an otherwise pretty sturdy planting border. They can shoot up flower heads like sentries from the back of a border, or create fountains in the middle of the border that shimmer in the slightest of breezes. They can even take prime position on the front of the border where they can arch over and blur the hard edge of a path or terrace.
There are many conditions that grasses will grow in. Hakonechloa, and some Carex and Luzula varieties will tolerate shade although are better in part shade. Other grasses are suited to hot and dry conditions and include Helictotrichon, Festuca varieties, Pennesitums and some Stipas such as Stipa ichu (which I am experimenting with in my own garden).
Grasses perform well into the late winter - the buff coloured seedheads adorned with frost look fantastic and atmospheric when seen glistening in the sunlight and contrasting with the black seedbeds of perennials.
Grasses, in even the lightest of breezes, create movement and texture and glistening light, and transform the borders, bringing light and life to the planting composition.
Planting plans can benefit by incorporating both cool climate and warm climate grasses.
Cool climate grasses are cool temperate varieties, and include our native grasses that can be used in the garden. Native varieties include Melica uniflora, Decampsia cespitosa and Briza media. Other cool climate grasses we use in the garden include Calamagrostis, Stipa and Molinia species (actually, we also have a native Molina).
Warm climate grasses hail from the parts of the World that experience longer daylight hours and higher diurnal temperatures! Warm climate grasses we can grow successfully in the UK include Panicums, Pennisetums and Miscanthus.
These two grass groups grow in different ways. Our cool climate grasses put on growth and flower earlier than their warm climate cousins. Some of the latter varieties you may find won’t even flower until October e.g. Pennisetum ‘Hameln’, whereas Briza, for example, will flower in the height of summer. If you use the rule-of-thumb that cool climate grasses flower BEFORE mid summer, and warm climates grasses flower AFTER mid summer, then this is useful when choosing your grasses.
Using both in a planting scheme will lengthen the season of interest with summer flowers on some species taking centre stage as the other put on basal growth. Calamagrostis, Briza and Deschampsia will all put up earlier flowers. Then later, (while the former are going over and drying out, creating an array of buff tones in the late summer garden) the purples, creams and greens of the Miscanthus, Panicum and Pennisetum flowers are entertaining us.
It is also important to note that maintenance of both these types also varies. Cool climate grasses can be lifted and divided in the late autumn and early spring, whereas the warm climate grasses are best left until later spring once they have put on a bit of growth. These grasses are also susceptible to winter cold and wet, so cutting these down in the winter can also encourage die back. Leaving the flowers on all grasses is always encouraged for winter structure and for a winter food source for our wildlife, but also in this instance to reduce plant failure of the warm climate ornamental grasses.
Grasses are still a marmite plant in the garden. Some clients will specifically state ‘no grasses’, and others will enthuse about them and request all manner of varieties to be included. There are also various design styles that benefit from grasses - coastal gardens, naturalistic schemes and contemporary styles for example all look great with a good proportion of grasses.
If you are unsure, we would suggest a nice small and tidy variety. Stipa lessingiana is a wonderful suggestion, and can be planted near the front of the border, and even now is still looking lovely and green with its elegant flowers still creating a transparent fountain over my nepeta. Not as messy or as clumpy as its better known close cousin Nassella tennuisima, in my mind totally outperforms and is a trustworthy starter grass. You can find information on other grasses for a wide range of situations on the RHS website.
I also always check if any family member suffers from allergies. We don’t want to fill a garden with an exuberance of grasses only to find out the infliction we have created on the family. I am personally incapacitated in early summer with hay fever. I know our native grasses exacerbates my condition, although I suffer for my job! I don’t experience any hay fever from the warm climate grasses interestingly.
If you are looking for a garden designer or need a planting design, then do get in touch. We design in Sussex, Surrey, Kent and South London although do travel further afield.
