25 of Arvensis’ key plants
1 Agastache ‘Blue Fortune’ The blue flowers are tiny compared to the hefty spike of calyces that carries them, meaning that once flowers drop cleanly, it offers additional structure for autumn and winter. 90cm. AGM*. RHS H6, USDA 5a-9b†.
2 Blechnum spicant One of several ferns grown at Arvensis for their atmospheric foliage, this hard fern is noted for its fertile fronds, which are markedly erect. 50cm. AGM. RHS H5, USDA 5a-8b.
3 Molinia caerulea subsp. caerulea ‘Heidebraut’ A compact grass that embodies both rigidity and grace. In autumn it becomes really eye-catching as it dies back. 1.5m. RHS H7, USDA 4a-9b.
4 Symphyotrichum ‘Prairie Purple’ A S. cordifolium hybrid that has inherited the characteristics of a mass of smaller flowers and
good mildew resistance. A tall plant with clear-coloured flowers and dark stems. 1.2m. RHS H7, USDA 3a-8b.
5 Eryngium planum ‘Blaukappe’
Even in their summer glory the flowers of eryngiums are dry and spare and this quality serves them well in old age. This is a small-flowered and multi-branching type of sea-holly. 75cm. USDA 2a-9b.
Cephalaria alpina A pale-yellow species that is alpine in the geographical rather than the gardening sense (it grows to heights of 1-2m). A good-mannered cousin of the better-known Cephalaria gigantea. 2m. USDA 3a-10b.
7 Asclepias incarnata The upright, pointy seedheads are a quite spectacular feature of this swamp milkweed, which also offers rosy-budded, scented flowers in summer. Tap-rooted, requires damp soil. 1.5m. USDA 3a-6b.
8 Bouteloua gracilis The flowers of this grass have the appearance of disembodied eyebrows, which has given rise to one of its common names, eyebrow grass. Another is mosquito grass, as the horizontal flower spikes appear to hover above the leaves. Drought tolerant. 60cm. USDA 3a-10b.
9 Melica ciliata Robert loves this grass both for the fact it flowers early in the year and because it tolerates a degree of shade. What’s more, if cut back in summer it can offer a second crop of flowers in mid-September. 45cm. RHS H6, USDA 5a-8b.
10 Vernonia arkansana ‘Mammuth’
Tall and robust prairie plant with dark-magenta flowers and fluffy seedheads in autumn. Great with tall grasses. 1.8m AGM. RHS H7, USDA 5a-8b.
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11 Geranium nodosum ‘Fielding’s Folly’ A newly named cultivar from breeder John Fielding that has a much darker, velvety flower colour than other cultivars of the species. Acquired from Tom Mitchell. 45cm. RHS H5, USDA 7a-10b.
12 Artemisia lactiflora ‘Elfenbein’ A more garden-worthy version of our native Artemisia vulgaris. Requires moisture to thrive, but given retentive soil presents its frothy flowers at a good height from mid to late summer. 1.5m. USDA 3a-8b.
13 Pennisetum alopecuroides ‘Cassian’s Choice’ Much the hardiest species of the foxtail grasses. The bottlebrush flowers look quite hefty on a compact plant and come into their own when backlit. The autumn colouring of the leaves sets up a lively contrast. 75cm. USDA 3a-8b.
14 Liatris microcephala Texturally interesting for its needle-like foliage. Robert admires its habit of shedding the old flowers cleanly and leaving a fine winter skeleton. A good all-rounder. 60cm. USDA 6a-9b.
15 Achillea ‘Terracotta’ Tall stems of ferny foliage and flat heads of rusty oranges and yellows that fade to cream late into the summer. Deservedly popular. 1m. RHS H7, USDA 3a-8b.
16 Persicaria amplexicaulis ‘Alba’ Slender, white spikes of flowers on bright-green foliage, best in light shade and retentive soil. Reliable, robust and low maintenance. 1.2m. RHS H7, USDA 5a-9b.
17 Persicaria campanulata Knotweeds are generally robust, competitive, well-performing plants with a touch of the wilderness about them. This has an extra level of refinement with its dark, sinuous stems and pearlescent flowers. 1.2m. RHS H7, USDA 5a-8b.
18 Rudbeckia triloba Masses of bright-yellow flowers with black eyes in late summer. Good upright structure into winter. Short-lived but worth it. 1.5m. AGM. RHS H6, USDA 3a-10b.
19 Allium hookeri ‘Zorami’ A white-flowered allium that just goes on and on, flowering and growing throughout late summer and autumn, sometimes even into winter. Can add a punchy freshness to borders that are dominated by decay. 90cm. RHS H5, USDA 4a-9b.
20 Sesleria autumnalis This grass presents strapping robust sheaves of a chartreusetype colouration – which is most refreshing to the eye when it catches the autumn sun. A great front-of-border buttress plant. 90cm. RHS H7, USDA 5a-8b.
21 Althaea cannabina Somewhat like a wiry-stemmed, herbaceous Lavatera, this is equally floriferous but lighter in all its parts, giving it a see-through quality. Late summer to autumn. 2m. RHS H7, USDA 4a-9b.
22 Parthenium integrifolium Unusual plant with knobbly white florets, like mini cauliflowers. Best in a sunny, well-drained spot. 90cm. USDA 4a-8b.
23 Calamagrostis brachytricha The Korean reed feather grass is similar in habit to the better-known Calamagrostis x acutiflora ‘Karl Foerster’ but its flower heads are much more diffuse. 1.2m. AGM. RHS H6, USDA 4a-9b.
24 Panicum virgatum ‘Warrior’ In appearance is as delicate and slender as any other Panicum but doesn’t shatter so easily. The flowers are brooding dark-purple clouds. 1.8m. RHS H5, USDA 5a-9b.
25 Succisa pratensis As well as providing food for the declining marsh fritillary butterfly, the native devil’s bit scabious is an excellent border plant preferring moist soil. Exceptional longevity of flowering on tall, wiry stems. 60cm. RHS H7, USDA 5a-9b.