• 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

First year flowering Gold Medal perennial

Penstemon ‘Twizzle Scarlet’ is a prolific new first-year flowering perennial

We tend to think of penstemons as large-flowered and blowsy, but the first of a new series derived from the American native Penstemon barbatus is rather different. And it’s won a Gold Medal from Fleuroselect, the Europe-wide flower seed trialling organisation.

Penstemon ‘Twizzle Scarlet’So what’s special about ‘Twizzle Scarlet’? Well, first of all its scarlet, tubular flowers are smaller and more slender than those of the more familiar varieties.

Needless to say, this is more than made up for by the tall upright stems along which flowers are crowded in clusters, producing a succession of bloom at each leaf joint.

The result is a long season of flower from July to September - from seed sown earlier the same year. For that’s its other claim to fame: this colourful perennial flowers well in its first year from a spring sowing.

Happiest in plenty of sun and in well-drained soil, ‘Twizzle Scarlet’ has a relaxed style that ensures it fits well into mixed and perennial borders where it should reach 70-80cm. It can also be cut for the house. When I saw it in the summer I admired its prolific flowering, its bright colour and its natural elegance.

You can order seed of Penstemon ‘Twizzle Scarlet’ from Plants of Distinction.


Please note, the contents of this blog reflect the views of its author, which are not necessarily those of the RHS.

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