Diarmuid Gavin: Light fantastic
'Floaty' flowers add an ethereal touch... their seemingly fragile nature brings romance to planting schemes
I've been journeying around Ireland, England and Holland over the past 10 days, and at last there's been plenty of flora to admire in the countryside - after our long winter and dispiriting early spring, the fields have never looked so green; hedgerows are heavy with May blossoms, and I even managed tantalising glimpses of the woodlands carpeted with bluebells.
I'm only involved in the Chelsea Flower Show on its periphery this year but seeing roadside verges full of cow parsley, Anthriscus sylvestris (right) - a favourite of show-garden designers at this time of year - reminded me of the circus which is about to happen. This wild plant has delightful ferny foliage and is topped with sprays of white flowers. Look closely and you'll see that the flowers are at the end of tiny stems splayed like an umbrella. This indicates that it's an umbellifer, and its relatives in the plant world include carrots, parsley, parsnips, angelica and celery. It's a useful plant because it belongs to a group of herbaceous plants that are best described as 'floaty' - they drift delicately through the border, their wispy white flowers appearing to float magically in the air.
Alongside the cow parsley, there's a whole range of other gorgeous umbellifers that provide a light elegance. Also flowering in May is Orlaya grandiflora, the white lace flower: a very pretty hardy annual which will keep flowering through the summer. Direct sow in spring or sow this autumn for earlier flowering next year. Or you can direct sow bishop's weed, Ammi majus, into the ground now and have lovely lacy white flowers later in the summer. For a touch of pink frothiness, try Chaerophyllum 'Roseum' (hairy chervil), which has lovely umbels of pale pink flowers. It's perennial but, with umbellifers, you don't lift and divide to propagate. Like their carrot cousins, they have a tap root. They're not fond of being moved anyway, so your best bet is to collect seed in autumn and sow while fresh.
Another Chelsea favourite whose flowers float above the throngs of planting is Verbena bonariensis (above). This striking plant produces a haze of purple flowers at shoulder height from midsummer through to the autumn. It makes a great cut flower plant; however, if you continuously pick the blooms, the flowering stems will shorten and broaden so you will lose some of the effect of the purple hovering above other garden growth. It's a perennial but doesn't last for years. Still, it's easy to cultivate from seed... just sow under cover from March, plant out after last frosts or direct sow into the soil in May. And 14 weeks later you will have flowers. It freely self-seeds so if you have it in your garden and you're not too careful about weeding, it should pop up again and again. Oh, and bees and butterflies adore it!
Also late in the summer and into early autumn you can grow Selinum wallichianum, the milk parsley, which has lots of lacy white flowers atop sturdy green stems. It's great for providing late-summer nectar - in fact, all umbels are great for attracting beneficial wildlife such as hoverflies.
But it's not just umbellifers that do this job. Other frothy or wispy plants you could include in your border are Valeriana officinalis, which I used in a Chelsea garden a few years back. It caught the attention of many visitors with constant cries of "what is it?". It's a tall native wildflower, commonly known as valerian or all-heal, and is commonly used as a medicinal herb to aid sleep. It has very fragrant white to pale pink flowers and is lovely in an informal or cottage garden.
Gypsophila, or baby's breath, is widely used in bouquets to give an airy contrast to more solid flowers and can perform a similar function in your borders by creating soft clouds of thousands of tiny white flowers. It's drought-tolerant, a good choice if we're in for a long hot summer. And towards the end of summer you could enjoy Sanguisorba: soft pink or white bottle- brush flowers atop stems a metre high.
So, if you think your borders looked a bit flat last year and you want a more romantic, dreamy effect, introduce a bit of frothy glamour this year!