Hazy days of Summer

Most gardeners know well the ‘summer lull’: that period from mid-July until the end of August when the garden can begin to seem lacklustre and the flowers look anaemic. The tidal wave of colour and excitement that built through May and June has peaked and the late-flowering perennials and shrubs have yet to move into the spotlight.Work in the garden also slows.The frenetic preparation of the soil, the mulching, mowing, sowing, potting up, and planting out that occupied the spring, is over.For most gardeners this is a tranquil time.

In the Glyndebourne gardens though, the borders maintain their colour and vitality and the gardeners’ workload is as heavy as ever.With a performance every day throughout August, they have to work speedily to get each day’s jobs done before audiences arrive to set up their picnics.

Head Gardener Kevin Martin uses a variety of techniques to keep the gardens looking good all through the summer. Dead-heading – removing flowers that are beginning to fade – not only keeps the garden looking fresh but also encourages the plant to produce more flowers because as soon as a plant is allowed to set seed it will stop flowering. Dee, one of a small group of garden volunteers, regularly works on the roses, cutting the dead flowers off at the base of the stem to ensure a display that continues all summer long. Potted pelargoniums are picked over each week to remove the spent flowers and encourage more. The spikes of verbascums and delphiniums are cut down to the ground as soon as their flowering is over: most will produce more flowers at the end of the summer.

Some plants are too floriferous to have their individual flowers picked off and they are often sheared back to a few inches from the ground.Hardy geraniums, oriental poppies and violas all respond well to this treatment. If you are doing this in your own garden, don’t be faint-hearted about it: use a pair of hedge-clippers and cut the whole plant back.

Early-flowering biennial plants, such as foxgloves (Digitalis purpurea) and sweet rocket (Hesperis matronalis) are dug up and removed as soon as they have finished flowering.

The most important aspect of keeping the garden in flower during the summer is the planting of annuals. Annuals are floriferous, long-flowering and colourful, and most are at their peak during the summer.In recent years the use of annuals has fallen out of fashion, seen as harder work than perennials; but at Glyndebourne they are used throughout the gardens to make sure that the borders are always vibrant. Using annuals means that new plants can be experimented with and the whole look of a border can be changed. Seeds of most annuals are sown between March and May, young plants are potted on in the greenhouse, hardened off in our cold frames, and then planted out as soon as there is space in the borders.

As well as using traditional annuals, such as cosmos, cleome and cornflowers, the Glyndebourne gardeners are always on the lookout for new and unusual varieties.In the hot border you will find the magnificent orange flowers of Tithonia rotundiflora ‘Torch’;on the terrace a group of the unusual cranberry-coloured tassels of Persicaria orientalis, dripping from the plant’s tall bamboo-like stems (in America this plant goes under the common name of ‘kiss-me-over-the-garden-gate’, which adds to its attraction).Old-fashioned and under-used varieties of plants are also grown, so in the blue border you will find the beautiful inky-blue flowers of Salpiglossis ‘Kew Blue’, a much-neglected cultivar.

All of this means that the beds and borders are as effervescent and as colourful in August as they were in June.