August on the allotment in Sheffield

It goes without saying that living, working and studying at RHS Wisley this past year has been an unfathomably enriching experience. And I’ve got one more year to go. It has also been a different kind of delight in parallel, to spend occasional weekends back at my home garden and allotment up north. Here’s what was looking good in August on the allotment in Sheffield.

The lower half of the allotment, looking out east towards Sheffield.

My allotment is like a sketchbook, with some beds used as testing plots and stock-beds, others are rough sketches, and others are more finely tuned. I have let myself be fairly free from aesthetic rules or principles, just editing what I don’t like and refining and expanding on what I do like, and taking some calculated risks along the way.

The heaviest soil is down the bottom of the plot, receiving full sun in summer but semi-shade in spring and autumn. Astilbes were asking for these conditions, as were sanguisorbas. I’ve trialled a load of geums there too, and come to the conclusion I don’t like any of them!

Left to right: Astilbe chinensis var. taquetii ‘Purpurlanze’, Calamagrostis x acutiflora ‘Karl Foerster’, Sanguisorba hakusanensis, Sanguisorba tenuifolia ‘Pink Elephant‘, Artemisia lactiflora, and seedheads of Geranium phaeum.

Biennials and self-seeders add a lot of dynamism. Every year there seems to be a different theme. Last year it was floaty white foxgloves and the white saucers of Lychnis coronaria ‘Alba’. This year, the verbascums and Digitalis ferruginea have created a different atmosphere altogether, alongside metallic Eryngium giganteum ‘Silver Ghost’. Sadly, almost all of the verbascums have leaned so far over I’ve had to cut them down. I’ll keep some going to collect seed from. I’ve realised the importance of letting them get their taproot right down; mine were too pot bound in 9cm pots when planted out, so their taproots were bundled up in balls that provided no stability.

Agastache foeniculum with Verbascum olympicum.
Digitalis ferruginea, the rusty foxglove, with Thalictrum delavayi ‘Splendide White’, Miscanthus sinensis ‘Flamingo’, and clouds of blue Eryngium x tripartitum in the background.

In autumn 2018, I planted around 500 Allium sphaerocephalon, for herbaceous perennials to be planted over the top. I dug deep trenches, a spade’s depth and width, and just scattered the tiny bulbs in. I find the deeper they are planted, the more perennial they are, and the stronger they stand up. Planted shallow, they seem to produce too many bulbils that make loads of foliage, and the few flower stems fall over. My soil is pretty heavy clay-loam, and they push up no problem. 

Helenium ‘Moerheim Beauty’, with Allium sphaerocephalon and Hylotelephium telephium ‘Purple Emperor’ in the background.

I’ve been trailing a few Monarda varieties that claim to show good mildew resistance. In my garden, the dark-leaved Monarda ‘Hauptling’ is faultless, and it’s a good job it’s my favorite too. When I get some time, this will certainly be divided up and sprinkled through a new darks and silvers area I’m planning.

Lythrum virgatum ‘The Rocket’, Stipa gigantea ‘Pixie’, Monarda ‘Hauptling’, Linaria ‘Cannon Went’, and Monarda ‘Squaw’ with Penstemon barbatus subsp. coccineus.
Echinacea purpurea, with Dianthus carthusianorum, Kniphofia and a background of Monarda ‘Hauptling’.

Penstemon barbatus subsp. coccineus is certainly a stand out plant for me these past two years during august on the allotment, grown from seed from Chiltern Seeds. I find the neon-salmon colour really curious. I find them to be a plant that requires the support of those around them.

Penstemon barbatus subsp. coccineus, Digitalis ferruginea, Leucanthemum x superbum ‘Broadway Lights’, Erigeron annuus, and Angelica.
The winged thorn rose, Rosa sericea subsp. omeiensis f. pteracantha, with Salvia nemorosa ‘Caradonna’.

One of the first plants I planted when starting the allotment 4 years ago, was a Sanguisorba ‘Burr Blanc’ from Dove Cottage Nursery in Halifax. I just can’t get enough of this plant, providing movement, texture, and transparent floating bobbles of white, turning toasty brown into autumn.

Sanguisorba ‘Burr Blanc’, with a violet haze of Nepeta, Linaria purpurea and Thalictrum delavayi. Eryngium giganteum ‘Silver Ghost’ in the foreground.

Erigeron annuus is another star plant for me, this year. Grown from fresh seed sown in autumn 2019, last year they were a bit underwhelming and flopped badly, but this year they’ve come up nice and strong. Their stems disappear like the strings of a puppet, leaving just clouds of white fizzing daisy flowers. Despite their name, they are short lived perennials. I don’t think I can have august on the allotment without them from now on.

Eryngium giganteum ‘Silver Ghost’, Stipa gigantea, Foeniculum vulgare ‘Purpureum’, and Erigeron annuus. Pale lilac comes from Allium ‘Summer Beauty’ and the taller ‘Millenium’ too, both fantastic somewhat rhizomatous alliums.

Up on the hill where the hillside was carved out to build a barn, we chipped out a few buckets of shale from the bedrock. We filled this old basin  that used to hold water for horses, and planted it up with some of our growing collection of sempervivums, mostly from Beth Chatto’s. 

Sempervivum table filled with local shale.

I’m gaining so much inspiration from Wisley, travels to wild places and other gardens. I will need to focus my ideas when I finish the course in a year from now. I’m really embracing all sorts of woody plants, but even on this double-sized allotment, I can’t go nuts like I can with herbaceous plants. Hardy succulents like some types of Opuntia (prickly pears) and Agave are also becoming an obsession. Who knows how this garden will shift in the years to come.