September in the Garden

At the time of writing, we are having a wet end to the summer, although I’m hoping that, just by stating that, the weather Gods will wake up and deliver us an ‘Indian Summer’ to balance out all the August rain…
In the ‘old days’, September was perceived as more colourful than the parched (!) weeks of August. The cooler, damper, conditions encourage bright, fresh, flowers on all those plants which are genetically programmed to perform during shortening day lengths. The evolution of garden styles away from high summer, peakiness, of herbaceous borders towards, what has become known as, ‘New Perennial’ plants has blurred this line somewhat.
Pre-dating the ‘New Perennial’ trend; Japanese anemones are a real treat at this time of year. When creating London gardens, my first job after graduating, the pure white Anemone x hybrida ‘Honorine Jobert’ was a mainstay of border designs. It copes well with shady conditions and, in my experience, flowers better when treated a little ‘mean’ and not grown with too much food and water. Newly planted specimens may take a few years to settle into a decent flowering pattern, I suspect they like to ‘get the measure’ of their plot before committing to making blooms, but, once happy, they are as tough as old boots. Strangely I don’t have it in my current garden because I chose a double, pink, form (A. huphensis var. japonica ‘Pamina’) when I should have planted ‘Honorine Jobert’’. One day I’ll correct that mistake…
Spiky flowering plants seem to hold sway this month. Persicaria, in all its varieties, continues to excite me and is peaking around now despite having been in flower for months already. My current favourite is the wiry beauty and simple charm of Persicaria amplexicaulis ‘Alba’; less boisterous than some of the larger leaved varieties and worth a place in any garden. Tall perennial grasses are the natural backdrop to all the late flowering, spiky, herbaceous perennials but I mention Miscanthus so often, in these musings, that I’ll not ‘big them up’ yet again.
Where would we be without Rudbeckia fulgida var. deamii (or its commercially available close substitute ‘Goldsturm’) in the late summer palette? It’s one of those foolproof herbaceous perennials that is just so hugely generous in every department (except scent). If it threatens to take over an allotted space, dig it up after flowering, replant one third and pot the rest up to plant elsewhere or give the divisions to friends who need cheering up. If it proves too floppy for your style of gardening then hem it in between shrubs or, those natural bedfellows, the perennial grasses such as Miscanthus (damn, I mentioned them again!).
It’s all the myriad species and varieties of the ‘daisy tribe’ (Compositae) that add so much vibrancy to the garden at this slide into autumn. I’m afraid that I’ve given up trying to keep on top of all the Latin name changes in the ‘daisy’ genera; it was pretty complicated three decades ago when I had to learn them first time around. I think if I just point you in the direction of ‘Asters’, ‘Heleniums’, ‘Rudbeckias’, ‘Echinacea’, ‘Helianthus’ et al then you can’t go far wrong. If in doubt take a look at what’s being posted on ‘Instagram’ for inspiration and then check for nurseries that stock them—they should have both the old and new names.
Social media will be awash with the favourite ‘comeback kid’ of the gardening world, the dreaded dahlia, but if you can wade through all the images of them (I guess they’re OK if you love staking and earwigs) then there will be plenty of even more colourful, not to mention perennial, members of the Compositae to inspire you as we leave summer behind and look forward to the planting opportunities that autumn affords.
On the shrub front hydrangeas must be the main group peaking around now. Even the big mop-head forms, which have been in flower for some time already, seem to swell and refresh with the added mistiness of lengthening nights and cooler days. The tall and graceful Hydrangea villosa is my favourite but I’ve noticed that the stonkingly confident blooms of Hydrangea arborescens ‘Annabelle’ have done particularly well this year. There is a pink form with a terrible name, ‘Tinky-Winky’, or somesuch nonesense, which has taken my fancy (if I was in the market for a new one).
……STOP PRESS………STOP PRESS……… I’ve just Googled it and discovered that it’s Hydrangea paniculata ‘Pinky Winky’ (told you it was a stupid name) so please don’t write in to our illustrious Editor complaining that I’ve given up totally on correctly naming plants (having been ‘let go’, by the BBC, for standing up for correct nomenclature, I think I’ve earned my stripes where using Latin names is concerned!).
On a maintenance note cutting hedges continues as does looking after the lawn with regular cutting and an autumn feed, towards the end of the month, to pep it up before winter. Now’s a good time to sow new lawns although if you are clearing the ground first, with glyphosate weed killer, it’s worth noting that September is getting towards the end of the period when these non-persistent herbicides will be effective.
I like to apply glyphosate to all visible bindweed growth as it will begin to die down soon and I like to get as much treated as possible in the hope that the underground portions will shrivel away over winter. At the time of writing I’m pretty sure glyphosate is still legal—but the debate over it’s safety (it’s safer than many chemicals you come across in everyday life) continues to blow hot and cold.
Planting bulbs should be a priority, as is preparing tender plants for coming under cover before the nights become too chill. I tend to take a few cuttings from them too, even though it’s getting a bit late for successful rooting; ‘nothing ventured, nothing gained’ and all that. Fingers crossed for a period of decent sunshine and warmth to aid rooting and also to give us time to actually get out and enjoy blooming September and all its charms.
Happy Gardening, y’all…