The jewel in the crown but the unsung heroes of the high summer garden have to be cosmos. The value of these simple, unassuming annuals cannot be underestimated, and they succeed in brightening and lifting any summer display. Ideal for cut flowers and for gaps in borders, cosmos are not only so easy to grow, but provide beautiful blooms for months on end, making them of undeniable value for any gardener.
Cosmos can be sown at multiple times of the year, starting in the colder months indoors to give them a head start, or even direct sown as the ground begins to warm. It is effective to sow these seeds in batches to allow a full display right the year round, and if sown in the summer they can be flowering a mere six weeks later. With excellent germination results, it serves to sow more rather than less, as drifts of these delicate flowers look magical threaded amongst roses, salvias, and other perennials. But while they make excellent gap fillers, the value of cosmos alone cannot be overlooked, with delicate and often detailed flowers that come in all sizes, from short, compact bedding ideal for pots or window boxes, to taller, flowing varieties which will peek up from amongst perennials.
The varieties of cosmos are endless, and they come in all shades, from bright white to pale yellow and deep burgundy, there is a variety for every colour scheme. Suiting cottage garden displays best, these annuals also work well in tropical and prairie schemes. Originating from Mexico, much like the dahlia, cosmos like well-drained soil and plenty of sunshine, which mimics their native environment. But unlike other plants from warmer climes, cosmos are very undemanding, and can even flower right through until the end of November, making them invaluable for a long and colourful display.
Famous varieties include ‘Purity’ – a tall delicate cultivar with large white blooms, ‘Sonata Pink’ – a bright pink coloured type, and ‘Daydream’ – an ombré toned cosmos with pale pink petal edges fading to a deep pink centre. While these old favourites are a must-grow each year, there are countless new varieties of cosmos released every season, and half the fun of growing these annuals comes from experimenting and discovering new and exciting types for your garden. For example, ‘Apricotta’ is an up-and-coming cultivar, with pale peachy tones. Cosmos ‘Seashells Mixed’ has more unusual, fluted petals in shades from the deepest magenta to baby pastel pink.
A huge range of the highest quality cosmos are available at The Rose Press Garden each year, either for early sowing at the start of spring, or for direct sowing as summer approaches. The monthly subscription box also ensures that you are up to date with all the new and upcoming varieties that are being seen in places such as Chelsea, not only for cosmos, but regarding countless other annuals and perennials too!
The only care cosmos will require is watering, specifically if grown in a pot or shallow bed, and taller varieties may benefit from staking, particularly if they are in a spot which may become exposed to high winds. Otherwise, deadhead frequently in order to keep the display fresh and energetic – however a few seedheads can be left to harvest and dry your own seed to use next season, particularly for those varieties which you have found to be most successful in your plot. Otherwise, if cut flowers are your thing, cosmos are an excellent plant to use, as the more you cut the more you get, and they will provide you with beautifully delicate flowers right through the summer and into autumn, ideal for weddings, gifts for friends, or even just to brighten your own interior!