The imposition of a hosepipe ban yesterday has made me rethink what plants I should be growing in my own and my clients’ gardens and how to keep a garden looking good without wasting water. I’ve been tasked with watering for several clients this summer which has enabled me to observe the effect of the drought in a number of different gardens. Just like us, some plants bask happily in exceptional heat and some wilt and wither. I’ve categorised the plants I’ve been monitoring into sufferers, survivors and thrivers. The sufferers have failed entirely or have had to be cut back prematurely. Survivors hang on grimly, but look far from happy and thrivers do not merely cope but positively burgeon in the heat.
The tough heart-shaped leaves of the bright blue flowered Brunnera macrophylla look dry and droopy. The usually resilient leathery leaves of the elephant’s ears (Bergenia) look scorched as do Heuchera leaves. If summer annuals like Verbena or Bacopa hadn’t established before the heatwaves, they have now given up the ghost altogether. The large leaves of Salvia amistad hang limply after a couple of days without water.
Although Japanese anemones such as the tall-stemmed white-flowered Honorine Jobert are at least beginning to flower, I’ve noticed their flower stems are shorter than usual. Hydrangea Annabelle is growing well in large containers in three of the gardens I maintain, though I can’t help thinking that this is due to their being targeted for special attention when it comes to watering. Their blooms though, usually at least 9 inches across, are very much smaller than in previous years. Evergreens like Skimmia Kew Green have developed that silvery sheen which denotes a struggle for water. Small-leaved salvias like Hotlips and Nachtvlinder (red/white and purple flowered respectively) cope relatively well.
But it’s not all doom, many plants have been in their element recently. Amongst them, whirling butterflies, Gaura, which billows with clouds of dainty white or pink flowers. Verbena bonariensis also revels in this kind of weather, those rigid stems standing high above some unhappier specimens below. Agapanthus have had a field day, in particular the large flowered evergreen species A. africanus. Several years ago I planted three stands of this stately plant in my tiny south-facing front garden and they now practically fill the space, self-seeding through the slate chipping and mirroring the blue of the annual Salvia farinacea Victoria which I’ve planted this year in the window-boxes with a delicate flowered pale pink Pelargonium cultivar, Apple Blossom.
Given their South African origins and dislike of over-watering, Pelargoniums have succeeded in my ‘pot garden’. So vigorously had P. sidoides grown in the large pot it shared with Rosa Bengal Crimson, I had to extract it before it took over entirely. In doing so I was able to pot up half a dozen of the plantlets which develop along its trailing stems. Regal Pelargonium Lord Bute has been magnificent, the crimson velvety petals with their paler pink edges contrasting with serrated mid-green leaves. I took a couple of cuttings earlier in the summer and shall take a few more soon to ensure I have more plants next year. Swept up in enthusiasm for this genus, I ordered some plants from Fibrex Nurseries Limited in Stratford-upon-Avon, holders of the National Collection of Pelargonium. Scented -leaved Fair Ellen has dainty pale pink flowers, the upper petals sporting maroon blotches and the leaves when rubbed evoking a herbal Mediterranean scent reminiscent of thyme. I chose the Angel Pelargonium Captain Starlight because I’d seen it grown by Andy Eddy, head gardener at NT Osterley and displayed on the steps of the Garden House. The leaves resemble miniature versions of Lord Bute and the flowers are pansy-like with two darker pink petals above three in a paler shade of pink. I also chose a species, Pelargonium grandiflorum, whose shell-pink flowers are centred with fine flecked cerise lines leading to the nectar source. I’m optimistic that like Lord Bute last winter, these treasures will be protected in the vertical cold-frame or on the shelf which I erected in the shed earlier in the year.
Glorious though they are once established and past the slug fodder stage, Dahlias are not on my list of drought-resistant plants. Native to Mexico and Central America, their fleshy stems and large leaves and flowers make them very thirsty plants. Of the seven or so I started from tubers and, in a couple of cases, cuttings early this spring, three have survived. One, with single scarlet flowers with bright orange stamens, was given to me as a tuber by a fellow volunteer at Osterley. Bushy in growth, with stems about 12-15 inches long, it’s a perfect specimen for a container. I’ve had to stake the tall single-flowered Dahlia Blue Bayou, which I first grew last summer after buying the tuber from Sarah Raven. Deep violet petals, darker at the base, surround a yellow disc. It’s planted in a large ‘Long Tom’ terracotta pot and is approximately 1 metre tall. Dahlias need regular deadheading and I can see many more spherical buds to come. Although resembling buds at first glance, the spent blooms are elongated and must be removed, stem and all, down to the nearest pair of leaves. I’m still waiting for the third specimen to flower, Dahlia Red Honka: another kind gift from my Osterley colleague.
For the last few weeks I’ve used ‘grey water’ from the washing-up bowl in the kitchen and a bucket in the shower, to water the pot garden. It was a relief when it rained last Wednesday and today, knowing that it would re-fill the water-butts. I’ve continued to use mains water on the nine tomato plants. I’d not intended to grow quite so many, but a neighbour gave away a selection of unusual cultivar tomato seedlings in late May and so I added Black Cherry, Green Zebra and Tigerella, to the Montello and Sun Gold which I was already growing. It was a good call as it turned out, as this hot sunny summer has hastened ripening. I made a very rich tomato sauce for pasta this evening using the Montello plum tomatoes. I’ve selected four of them to enter into the Kew Horticultural Show which takes place this Saturday. Watch this space for the outcome!
At Osterley’s cutting garden, we’ve picked bucket-fulls of flowers for drying for the Christmas wreath-making: Limonium sinuatum (statice) with its rainbow colours. And lavender, the flowers now spent. It’s a great opportunity at this time of year to trim the stems back, including a few leaves at the base, neatening up the plant and ensuring it doesn’t become too leggy and woody. We tied a length of garden twine around bunches of each of the statice and lavender, leaving a generous tail with which to hang the bunches to dry in a shed in the vegetable garden.