How the notorious British weather produced a magnificent midsummer flowering

I look on this weekend as the garden’s half-term. The first half begins in April and the end of the second is postponed by current non-winters until mid-November. For a month in Britain the conditions for gardening have been heavenly. Count yourselves blessed, new gardeners won in the months of lockdown. You have had a dream of a beginning.

I know not everybody has, whether in hot, dry Canada, the north-west of the US or in parts of France hit by “une chaleur étouffante”. In Britain, long memories make me quick to fear the worst. While bedding out in the first days of June, I saw a blood-red full moon and thought fearfully of 1976: it barely rained in that grim summer from early June until late September.

Fortunately, this year’s ominous moon came to nothing. Just as the young tobacco plants were wilting, the rain arrived and the cool returned, bringing the loveliest weeks for summer gardening since the mid-1980s.

There have been so many winners, but I have to pick on peonies. Their season has lasted extra-long without great heat to rush them through it. They have loved the combination of a dry May and a cool mid-June. They remain essential choices for gardens, especially urban ones, as they will grow well in light shade.

Between my peonies in a new bed I have sunk pots of martagon lilies to pick up the baton when the peonies’ flowers fade. They are now coinciding.

The important thing when planting a peony is not to set it lower than the previous level of soil in which it has been growing. It will probably be bought in a pot, so this level is easy to see, but if it is bare rooted, a soil mark will show at the point where the roots joined the upper stems. If peonies are planted too deeply, they are reluctant to flower.

Well-prepared soil is essential too, enriched with plenty of compost and if possible, rotted manure. Put some Growmore fertiliser in the bottom of the hole you dig for them and, in their early years, try to feed the plants monthly in the growing season with fertiliser dissolved in water, phostrogen being my mainstay. A well-fed peony is twice as good as some of mine.

Try the wonderful double-flowered white Festiva Maxima with red flecks in the flowers, the late-flowering pink double Sarah Bernhardt and, if you can find it, my favourite, Kelways Glorious, a heavenly shade of double white tinged with lilac pink.

Roses have been having such a superb year that they need no further comment. Cool days with intermittent cloud have kept them at their peak for so much longer. Until two years ago, I had been slow to discover that the ideal companion for shrub roses is one of the hardy geraniums, the aptly named Blue Cloud. Single flowered and a pale sky blue, it is amazingly easy to grow.

It is not invasive. It grows about 2ft high and radiates outwards from a central clump of roots. After flowering, all of its top growth should be cut back to ground level, encouraging the plant to produce tidy new leaves and a few more flowers later in the year.

On my travels to other gardens, open under the National Garden Scheme, I have noticed how there too, Blue Cloud is beset by bees. They love its open flowers. While I ate an excellent slice of fresh chocolate cake, feeling virtuous for helping the nation’s nursing and health charities, recipients of the profit, beside me bees galore were enjoying their own tea party on one of these geraniums.

Plant Blue Cloud and add some catmint elsewhere in the garden. In June your bee-conscience can then rest easy. I counted 23 bees, most of them bumbles, on one Blue Cloud in full glory. It is not a “native” plant. It arose as a chance seedling in a garden, probably from the excellent blue geranium Orion. Bees do not prefer native pollen.

A good year is a prompt for the next one. Early July is the peak viewing time for campanulas, the other great companions to midsummer roses and flower borders. Every garden should have blue and white Campanula persicifolia, one of those beauties which then self-seeds into clever places and never fails. The clumps of leaves at the base of the 2ft-tall stems can be divided whenever the weather is cool and redistributed round the garden.

They have such charm. If you have yet to embark on their path, use this week to sow a packet of their seed in a box of well-watered seed compost and expect it to germinate, even outdoors, within three weeks if kept away from cats. The seedlings can then be pricked out into another box, four or five to each row, and potted on in late August to make next season’s crop of bellflowers.

Once Campanula persicifolia is in the garden, it is fully perennial, an essential ingredient in any plan that combines formality of design with informality of planting.

In the slow approach of summer twilight, foxgloves have been magnificent too. Like me, they dislike hot summers and so they have flowered and lasted in prime condition. Bees bumble on from Blue Cloud to foxgloves and squeeze into their foxy flowers before rounding off on catmint: there is no need to worry about other plants being “good for pollinators” or not.

While I ate an excellent slice of chocolate cake, bees enjoyed their own tea party on a Blue Cloud geranium

Last year I emphasised the value of foxgloves for any garden’s all- important vertical line. I then sowed a packet of Dalmatian digitalis, one
of the best selections with flowers that still look glove-like. They have been excellent this past month and I recommend a sowing of them now by all newish recruits who want to move on to plant propagation.

Foxglove seed is very fine, so it should not be covered with yet more soil when scattered on a firmed-up, pre-watered seed compost in a seed box. Leave it on the surface, pressed into the soil, and keep it watered occasionally from a watering can with a fine rose on it to make a gentle spray. The seeds will germinate even faster than the campanulas.

Among summer’s shrubs, meanwhile, deutzias have been outstanding. I am a great supporter of these white or pink-flowered beauties, mainstays for June and July. They have no scent, but bees love them too. My recent winners are pure white Deutzia monbeigii, commemorating a French Catholic missionary in China, and Pride of Rochester, commemorating Rochester, New York, not Jane Eyre’s lover.

Pride of Rochester grows about 5ft high and wide and has the most subtle variation of pink buds and hanging pink-white flowers. All deutzias are extremely easy to grow in any good soil.

Near the end of the drought in May and early June I encountered a cluster of undergraduates, just released from evensong in the college chapel. I asked them near our deutzias whether they could pray usefully for rain or whether they were too wicked. “Both,” they replied with relish and within hours, were followed by a clouding of the sky and the welcome return of rain. Even in miserable lockdown, the student body still commands a hearing.

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