• AGM plants

    AGM plants have been through a rigorous trial and assessment programme. They are:

    • Excellent for ordinary use in appropriate conditions
    • Available to buy
    • Of good constitution
    • Essentially stable in form & colour
    • Reasonably resistant to pests & diseases

Blackest of the black

New heuchera challenges for the title of blackest foliage of all

Black-leaved heucheras are always appealing – they have darkest foliage of almost any perennial. For many years, ‘Obsidian’ has been the gold standard but now it has a challenger: ‘Black Pearl,’ which is new in the 2018 RHS Plant Finder.

Heuchera 'Black Pearl'So what makes it special? Well, the colour for one. While ‘Obsidian’ very definitely has red tints in the foliage, ‘Black Pearl’ has almost none and it keeps its colour even in full sun.

The leaves are also prettily waved and scalloped around the edges, giving the whole plant extra appeal; the leaves of ‘Obsidian’ are more or less unwaved.

Underneath, the leaves are rosy purple and the ruffling reveals sparks of the red colouring. The leaves are glossier than the more satiny foliage of ‘Obsidian’ and develop a faint silver sheen as they mature. The leaf stalks are also a little shorter than those of ‘Obsidian’ and other dark varieties, making a tighter mound.

On top of all that, the white summer flowers emerge from pink calyces, creating an attractive bicoloured effect and are lovely cut for informal bouquets.

This is also an adaptable plant, it will take high summer heat and icy winters. Good in containers, it’s also valuable at the front of borders and it’s not only the flowers that are good for cutting – those leaves make striking additions to small bouquets.

‘Black Pearl’ is one of the latest introductions from the wide ranging perennials breeding programme developed by Hans Hansen at Walters Gardens in Michigan. "We have been working with heucheras many years," he told me. "From a young age ‘Black Pearl’ stood out in a sea of seedlings. With its large glossy black leaves, scalloped margins and good growth rate it has become one of our finest introductions. “The new black” in the heuchera world."

You can order ‘Black Pearl’ from RHS Plants and these nurseries.


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