Plants for hot, dry weather

Posted in All Gardening Advice, June, on

We will all remember the spring of 2011. Like the summer of 1976, it will stick in our minds. We had the warmest April since national records began in 1910. A maximum temperature of 81.5F (27.5C) was recorded at Wisley on April 23 2011, conditions you’d expect on a good day in Crete, not Surrey in the middle of spring.

Sunshine across the country was around 150 per cent above average, and it was the sunniest April since 1929. There was also a distinct lack of rain: where I live on the Kent/Sussex border, we had only 20 per cent of our normal rainfall, with only two hours of proper rain in April and May.

 

Winners and losers

Some plants thrived in that southern European environment. It was a magnificent year for peonies and bearded iris. And the roses were happy too. I certainly had less black spot on my organic rose garden than I usually did at that stage of early summer. Alliums thrived, with the flower heads of the sparkler varieties such Allium schubertii even bigger than usual.

It was also a good year for butterflies - there were lots of orange tips, brimstones and blues about. Rare species such as the dingy skipper and duke of burgundy also did very well and adonis blues emerged in higher numbers than we'd seen for several years.

However, there were many plants that did not do so well. A lot ran to seed in a trice in the heat. Tulips were incredibly fleeting; my Iceland poppies and aquilegias came and went very rapidly.

Wild flowers were frazzled, the countryside looking very different to the previous year. The bluebell woods, cowslip-studded motorway sidings, snake’s head fritillaries and cow parsley all came and went within a matter of days. I drive through the village of Hawkhurst in Kent almost every day and, whereas the previous year it's small village green was swathed in a light pink gauze of cuckoo flower, there was not a hint of pink in sight in 2011.

So in hot years you really need to know your marathon plants — the ones that keep going for months, putting on a good show whatever the weather.

Marathon performers

Euphorbia

It’s hard to beat the large drumstick Euphorbia characias and I’d say 'John Tomlinson’ is the brightest and best of all. I have 20 to 30 of these on a south-facing bank and every year, including the heat of 2011, they have provided an undulating swathe of acid-green from late February until mid June. They did not bat an eyelid at the extraordinary weather.

We deadhead them at the end of their season, removing the year’s flower spikes down to the ground to make room for the following year’s emerging from the base. Then, tidy as you like, their healthy tussocks will give a good grey-green backdrop for the rest of the year.

Artichokes

Globe artichokes and cardoons are also must-have marathon performers, which look better than ever in the heat. Their foliage emerges as one of the first things in February, the jagged silver leaves a brilliant backdrop to hyacinths, tulips and alliums through the spring. Then come the buds and purple thistle flowers in early summer. The key thing with this family is to cut the plants right to the ground at the end of July. Give the roots a good water and up they’ll come again in a few weeks, the leaves bright and fresh, to give you a second crop of flowers to eat and admire through autumn.

Stipa

Stipa gigantea is on this list too, another background foliage plant, rather than a showy flower, but it has an incredible presence for more than half the year.

In early summer, its curving wands of oat-like flowers unfurl from its evergreen tussocks, gradually climbing to their full height of up to eight feet. There they stand, elegant and airy, ripening from green-gold to the full blown straw colour of an August arable field until they get whipped away by an storm in October or November. Interplant them with other long flowerers such as Cosmos 'Purity’ or Nicotiana sylvestris and you’ve got a low-maintenance combination which looks good for at least four months.

Hydrangea

Hydrangea paniculata 'Limelight’ is the first of two flowery plants to add to this essential list. It opens the cleanest, brightest, acid-green, like the guelder rose we all loved in the royal wedding flowers at Westminster Abbey.

Looked at more closely, the hydrangea has a brilliant architectural, chiselled flower, unfurling to cups in a green-washed-cream. Then the flowers fully flatten and turn pure ivory, before being washed with rich pink, the last stage before they gracefully brown and dry on the stem. Overall, the flowers give you an amazing succession that lasts from August until January, or even longer if the flowers are not thrashed around too much by the wind and rain.

Dahlia to die for

Finally, Dahlia 'Rip City’ is the number one, longest-flowering, lowest maintenance, catwalk model good-looking plant in my garden. I’ve written about this dahlia many times - but each year it impresses me, with its flowers cut from the deepest, silkiest crimson velvet. One plant will be covered in 20 or 30 at one time, each one filling the palm of your hand. They thrive on zero TLC, bar a stake at their side to prevent the vast plants collapsing under their own weight, and a bucket of compost over their heads at the end of autumn.

Also shortlisted…

There are so many other possible front runners – Rosa x odorata 'Mutabilis’, Rosa moyesii 'Geranium’ (flowers followed by decorative hips), the exceptionally long-flowering annuals such as Cosmos 'Dazzler’ and Cosmos 'Antiquity’, Helianthus 'Vanilla Ice’, as well as cleomes and verbenas such as Verbena bonariensis, Verbena rigida and 'Aztec Violet’.

However, my shortlist of five plants will yet again this year outshine any others – and will do so for week after glorious week.