I write this on the hottest day of the year so far, with 31.8 celsius (90-ish in Fahrenheit) registering in the shadiest part of my back garden. We do certainly seem to be having more of this sort of thing in recent years than we did in the now distant days of my childhood, and maybe, therefore, our gardening ideas need to turn towards plants that can cope with extreme weather, both in terms of heat (average spring temperatures in Britain have increased by almost two degrees Celsius since 1970), and the almost total drought we’ve been experiencing since early this year (spring 2025 was the driest in the UK since 1974, and only the storms of late May prevented it from being drier than any since Met Office records began in 1884).
I have definitely found it necessary to water my garden more than usual this season. Perennials have particularly suffered (my herbaceous paeonies look distinctly frazzled, and they're not alone), though it was a wonderful year for sun-loving irises, while deep-rooted shrubs such as roses romped away, showing no signs of distress, and finishing their first flush of flowers several weeks early. I even have a mature, large-leaved ivy, Hedera “Ravensholst”, in full sun for eight hours a day. Though ivies prefer shade, it hasn’t drooped for a moment.
A more Mediterranean style of gardening is often advocated as a way of coping with drier and hotter growing conditions. Many plants native to that climate have special adaptations: minute hairs on their leaves that retain moisture, as in Stachys byzantina (Lambs’ Ears), Verbascum (Mullein) or Lychnis (now renamed Silene) coronaria (Rose Campion), notably all grey-leaved rather than green: almost all grey-leaved plants love the sun. Some plants use their fleshy leaves to store water: one of the most familiar to British gardens is the succulent Sedum spectabile (now long-windedly renamed “Hylotelephium”, but known to us all as “Ice Plant”). Others have fleshy roots that do the same - these include Aloe vera and Agaves, nearly all of which are too tender to survive a British winter, but for how long will that remain the case?
Shrubs that work well in heat and drought include cistus, ceanothus, and helianthemum (sun rose), while some of the hardier shrubby salvias also adore such weather, flowering for months from early summer (these are mainly hybrids or varietals of S. x jamensis, like “Hot Lips” and the other “Lip” ones that have appeared recently; some might prefer the solid-coloured varieties like “Nachtvlinder”, a wonderful dark purple). Also consider planting euphorbias (spurges), which have become increasingly popular lately: they love sun and cope well with drought, have unusual flowers, usually in shades of yellow or green, foliage that rarely looks tatty, and require little maintenance. Some are tiny, like Euphorbia myrsinites, that creeps about at ground level, but others can get really big, making a bold statement – in the village there is a Honey Spurge, Euphorbia mellifera, more than six feet high and six feet wide.
A word of warning when planting all of these: make sure drainage is as good as possible. We have a lot of clay in our soil here, so mix in plenty of grit and compost (preferably based on coir or another peat substitute - it needs to have an open texture). Winter wet causing sogginess around roots kills far more plants in Britain than a couple of degrees of frost.
For more advice on “The Dry Garden”, I heartily recommend Beth Chatto’s book of that title (and she was true to her word, constructing a marvellous xeriscape gravel garden, eliminating the need for almost any watering, on the site of a former car park).
Another avenue to explore is "exotic gardening", turning your outside into a (semi)-tropical jungle. This is radically different from our English traditional stlyle, but can be spectacular. If considering this, take inspiration from the Exotic Garden at Great Dixter (https://www.greatdixter.co.uk/visit/garden/garden-estate-tour/the-old-rose-garden), where it really does feel as though a tiger is lurking amidst the greenery. Christopher Lloyd, the creator of that garden, also wrote the excellent "Exotic Planting for Adventurous Gardeners", now available cheaply second-hand. In the winter, you’ll need a lot of frost-free storage space for cannas, bananas, and the like: in rural Oxfordshire we don’t enjoy the favoured conditions of, say, Ventnor Botanic Garden on the Isle of Wight – they have bananas 30 feet high, left outside all year. One of the best nurseries for exotica is at The Walled Garden at Frampton-on-Severn in Gloucestershire – they do very tempting mail order (https://panglobalplants.com).