Art by accident

Phlox paniculata Eventide and Red Flame; Monarda Gardenview Scarlet

We are halfway through the summer and I doubt if gardeners have ever had a more testing year. In Greece they have been scorched in a heatwave. In the grain-belt of America they have been driven to despair by drought. Anyone who tried to organise a village fete or an open day in Britain’s early July has been washed out. And yet, through it all, there have been some of the best garden moments in my memory.

It has not been a year to be a Morning Glory plant or even a basic sort of marigold. Mine went out with love and best wishes in early June and before I could reach for the Provado bug-spray they were stripped of every green leaf in their first night outdoors. Morning Glory hates a damp, cool start and in wet weather I have just learned that it appeals to slugs on the prowl. If I were a thrip or a greenfly I would never sink my teeth into a pungent tagetes. Here is the first lesson of the summer. Even an aromatic marigold is not safe when pests proliferate. From now on I will soak their compost in the unbeatable Provado before bedding them out and I will let them stand for a day or two so as to soak it up. They are then safe from attack for the next two months.

Meanwhile other plants have run riot. Anything that spreads has spread as never before and I am having to intervene early in flowerbeds to keep the peace. Autumn’s yellow-flowered Helianthus has doubled its territory and shown bigger and greener leaves than ever on my quick-drying soil. Feathery white-flowered Arundinaria is invading all neighbours and the worst offender is the yellow-flowered Inula hookeri, which entered my garden as a gift in a plastic bag from the great plantsman Christopher Lloyd. Its flat gold-yellow flowers are attractive but it runs all year and I cannot wait until October to reduce it. Was he smiling to himself when he gave me a bag of roots at Great Dixter? It has to be curbed now.

If you are being invaded, intervene and let the neighbouring plantings breathe. Otherwise just look at the amazing heads of flower on phloxes and Crocosmias. They are often best in the cooler north of Britain but this year’s summer rain has transformed them in the south. My borders have been glowing as never before and, just for once, I have felt artistic. It has turned out that the best blues and cool colours are in the foreground and the fierier shades then develop in the distance, set off by blocks of strong white. This effect was never planned but it is fun to spin a story to imply that it was. Artistry has happened by accident.

The phloxes are twice as lovely as ever and the deep lavender blues are the best. I treasure the brilliantly named Phlox Toits de Paris as it really does have flowers that resemble the view across the slate-blue roofscape on Paris’s Left Bank. Mine have the look of the roofing of the Rue de Seine. However, the classifiers are in turmoil and the RHS Plantfinder even tries to distinguish Toits de Paris ambiguous from Toits de Paris misapplied. The truer name, they try to legislate, is Phlox Cool of the Evening, but I cannot see what fine line they are trying to draw.

Crocosmia Lucifer

Phloxes with bluish flowers are especially lovely in the evenings as the temperature drops. Eventide is a classic but my winner for flower-heads and impact is Skylight. If you are wanting to go blue in late July, Skylight is the best. It flowers so freely and all you have to do is dead-head it quickly and continue, if possible, to give its mat of roots some liquid fertiliser every fortnight. Last year it flowered well with me again in autumn and this year it looks as if it will never stop. There is not a hint of mildew.

The sights of the week are the Crocosmias. They are all excellent but my personal favourite remains the tall crimson-scarlet Lucifer. This year it is leaving all rivals behind. It has grown up to nearly 5ft and covered itself in those heads of flower which it holds flat, asking to be admired. When Crocosmias first became fashionable in the 1960s, we were told that they might not be fully hardy. The place for this South African family seemed to be a hot dry bed facing south under a wall. In fact they are plants which like plenty of water, and sunshine too. For years I held mine back by hot-bed treatment. This year has wonderfully made the point. Crocosmias will grow and glow with fresh green leaves if they are constantly rained on in the early summer. In the interlude of sun they then flower spectacularly with intense colour. No wonder some of the best varieties have flourished in Irish gardens.

Agapanthus Loch Hope

Exactly the same effect is visible on those other South Africans, the agapanthuses. They have set more buds than ever and will sweep through August in a procession of blues and whites. Again they were feared at first to be tender in Britain but our knowledge and range have been transformed by breeders and selectors. Top of my shopping list is now the brilliant deep blue Agapanthus Loch Hope, a hardy and spectacular performer. If you are starting out with a new border, do not miss this excellent variety. The Plantfinder lists 20 suppliers all over Britain, so buying it is not a problem.

When the crowds calm down, I will certainly go to see the London Olympics’ “sustainable” borders. Their brief, plainly, was to use wildflowers and the mastermind, Professor James Whitmough, has even revealed that the initial suggestion of the Olympic commissioners was pink-flowered Rose Bay Willow Herb. Heaven help them: it is a class-A invasive weed. The results have been excellently timed in such an unpredictable year but I doubt if I will prefer yet another long strip of “wild flower mix” to the depth of colour, variety, persistence and sheer beauty of my straightforward borders. New varieties, new chemicals and new plants from the wild continue to put such new life into the “traditional” English border and it would have been fun to have shown more of it to the world. I much prefer my special effects this weekend to yet another mass of ox-eye daisies and wild carrot out of season, even if the Olympic torch once passed nearby. And the dahlias are still to burst out, never better than in this wet, now steamy season. By then the Olympic wild flowers will be shut to visitors.

Meanwhile, many of you have written in for more details of the fine study of “Pulhamite” rock landscapes by Claude Hitching and some of you even wonder if you too have a Pulham rockery lurking in the garden’s outer reaches. The book is Rock Landscapes: The Pulham Legacy by Claude Hitching, just published by Garden Art Press and available here and in America through the Antique Collectors Club (www.antiquecollectors Claude Hitching also runs a fascinating website with up-to-date details of research into Pulham rock landscapes ( If you want to check the credentials of your rockery this site is the answer. Meanwhile, the Pulham trail adds a fascinating new strand to summer garden travel, adding to a season in which gardens have suddenly started to glow.

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