• 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

American updates on a classic European perennial

A familiar perennial spawns a fine, bee-friendly improvement

In 1960, ‘Hummelo’, an improvement on the British native wildflower and cottage garden perennial Betonica* officinalis, was named for garden designer Piet Oudolf’s garden by plant breeder and nurseryman Ernst Pagels. It became one of his signature plants and he used it in his designs all over the world. Now, from America, comes a valuable paler variant: ‘Summer Romance’.

Betonica 'Summer Romance' (above) and 'Summer Crush'This is a long-flowering, clump-forming, summer perennial with upright flowering stems emerging through a mound of aromatic foliage.

‘Summer Romance’ features compact tiers of small two-lipped flowers, crowded into a spike at the top of the 60-75cm stems from June to September and spaced out a little more lower down.

The flowers are paler than those of ‘Hummelo’, almost silvery pink on the back creating a soft two-tone look, and carried in longer clusters packed with more flowers.

It was developed by Brent Horvarth of Intrinsic Perennial Gardens in Illinois who, in 2009, sowed open-pollinated seed of ‘Hummelo’ and selected ‘Summer Romance’ from the resulting seedlings the following year.

At the same time he also sowed open-pollinated seed of the tall pale pink, but rarely seen, ‘Pink Cotton Candy’. From the resulting seedlings he selected a delightful bicoloured variety, ‘Summer Crush’, for its longer, lighter pink and more elegant flower clusters. The flowers open in succession within each tier, the rich rosy buds opening to blushed white flowers, with both shades prettily mixed in each throughout. ‘Summer Crush’ is taller than ‘Hummelo’, at 75-90cm, but with those unique bicoloured flower spikes.

You can order plants of Betonica ‘Summer Romance’ and ‘Summer Crush’ from Hayloft Plants.

*Nomenclature note: These plants have switched back and forth between Stachys and Betonica over the years but are now confirmed as correctly named as Betonica officinalis, although all are still sometimes sold as Stachys.

Please note, the contents of this blog reflect the views of its author and do not constitute an official endorsement by the RHS

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