The flowers that are raining champions of Britain’s wet summer

In Britain, primetime gardening has so far been a tale of two seasons. I like to take stock at a halfway point in the summer months. They began after a dry May which filled gardeners with foreboding. Even in Britain we feared a repeat of 2022’s overheated marathon. Against expectations, the heat has stayed to the south in Europe and we have had dream weather for gardening: cool, wet and seldom too sunny without the interruption of clouds.

The effects have been interesting. By August I would expect even newly planted dahlias, rooted from spring cuttings, to be in flower, but mine have progressed only as far as flower buds and a few half-opened petals. It is remarkable how some of them came through last winter even when left in the ground, but only now are they flowering as they should. Give yours a feed with diluted Tomorite, two tablespoons to a gallon of water, as it encourages flowers from now on. Be sure the plants are well staked as the weight of flowers will flatten them.

I dread a dry final week in May and a dry first week in June, as they are the time in Britain for planting out the summer’s bedding plants. In hard dry soil the job is a tough one, so I soak the ground from a hose for a morning before planting in the cool of the evening. I also dip every plant’s root ball in a bucket of water until the bubbles cease to appear. Bought-in bedding plants are grown in light compost which arrives in shops still dry in its centre. Dry-planted bedding never fully recovers, so this dipping is essential.

In May I failed to dip three trays of homegrown sweet peas. Of all bedding plants, they are the ones which most hate to be dry. When I found them mine had signs of green on only a few of their shrivelling shoots. I planted them shamefacedly but for once mother Nature has graciously rescued an oversight. Her wet and cool conditions since mid-June have turned the plants round and they are now green and beginning to set buds. In most gardens the first crop of sweet peas was disappointing, so I have not missed too much. In a muddled calendar I am about to enjoy April in Paris, a sweetly scented variety with pretty lilac pink edges to its off-white flowers.

After a stupendous first flush of flower on all the roses, we have had a superb year for lavender. It too enjoyed the dry May and has flowered prolifically in the wake of it. Last autumn I passed on the excellent advice of an experienced lavender grower: cut old plants down to about 6in from the ground in April. For once I remembered, seven months later, to act on it.

The treatment works very well. It has delayed my lavender season, but the old bushes are no longer leggy and their flowers are just coming on stream. Try an April cut on some, but not all, of your lavenders next year in order to stagger their season and prolong the general show.

I still rate the dark blue, low-growing Hidcote variety above all others for British gardens. Fancy lavenders from Provence and the Canary Islands are pretty, but they died in Britain’s recent winter. In Europe’s heat, they have been as good as usual.

In mid-July I was still puzzling over the damage which last winter had caused. For the first time ever, the plants of Clematis montana on my garden’s arches remained brown in April. They were the pretty pink-flowered variety, Mayleen, ranked hardy in zone 6, but they were still totally brown on July 14. I asked others nearby and found my plants were not alone. The winter has indeed killed them and has also killed an elderly Clematis Bill Mackenzie, a veteran of every winter since I planted it in 1987.

I have not followed the usual advice to take the opportunity to plant something different instead. I have planted the same again, because I want these life-long favourites and they have always been hardy until this extraordinary year.

Hollyhocks fill the mid-July gap, bringing the high vertical line which adds such class to a border

Other old favourites sprang back to life from early July onwards, but they never included hebes, daphnes and most of the cistuses with aromatic leaves. To my regret, some of the buddleias sprang in the wrong direction too. Even that vigorous variety of Buddleia davidii, Royal Red, began by showing some new growth in April after the winter had cut it down to the ground, but by mid-July those shoots were wilting: what remains of the plant looks beyond repair.

Last week I visited a nearby National Collection in order to compare its results, but it too, had lost about 25 per cent of the buddleias: they had died back without rhyme or reason, Royal Red among them. On some of them, new growth eventually appeared low down on the plant and as buddleias are seldom grafted, this growth, if it survives, will be true to what was planted. Other buddleias have wilted, like mine, after trying to reshoot. They look set for the scrap heap, a loss I never expected.

On a happier note, the profusion of roses and lavenders has been followed by a profusion of hollyhocks. Their stems have stood up strongly and rust disease has not ruined the leaves, perhaps because the recent weather has been cool and wet. Flowers have been prolific, even on plants which have cleverly self-seeded into cracks in paving or below a fence or a house. Hollyhocks fill the mid-July gap, bringing the high vertical line which adds such class to a border.

In honour of this vintage year, look for young hollyhock plants in 9cm pots and plant them immediately with next summer in mind. There is no need to buy these rapid growers in two-litre pots for £8.95 each or more. Hollyhocks flower well as biennials in the summer after planting: I like to mix and match dark maroon-flowered ones and white ones.

It is not just the daytime weather which has been odd. Nights have been remarkably cold, leaving dew on the lawn even in supposedly balmy August. These night chills have held back annuals and intensified their colours, inclining me to a mad experiment. Throughout May, the ground was too dry and hard for us to sow annual seeds directly into it. As a result I am short of nasturtiums, those trailers to my autumn gardening.

To compensate I have just sown a packet of them, three months late, in workably wet soil, gambling on prolonged mildness again in autumn and a final flowering in November. They may make the grade, giving a last burst of warm colour in a summer which has belied its dry beginning.

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