• 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

New royalty among buddleias

Dwarf but elegant, these new buddleias from America never get too large yet always look graceful


We’ve seen a lot of new buddleias introduced in recent years, adding new hybrids, new features and new styles to a favourite summer shrub. But since the Buzz Series arrived back in 2009 we’ve not seen a significant development in buddleias in the traditional style [as opposed to cultivars of weeping buddleia such as 'Unique']. Until now.

Buddleja Monarch SeriesPlants in the Monarch Series look like scaled-down versions of traditional buddleias (Buddleja davidii). I asked Tom Stimpson, Plant Product Manager at Woolmans who are introducing three varieties from the series this year, why he thinks these Monarch Series are so special.

'I saw the Monarchs flowering in trials last year,' he told me, 'and they immediately stood out for their well-branched habit and sheer number of flowers. I liked the fact that the plants were a little taller than other dwarf types, such as the Buzz Series - they just looked a more natural, rather than just dwarf. The flowers were larger and appeared more elegant. Good weather tolerance too.'

The Monarch Series of buddleias were developed at Walters Gardens in Michigan by Hans Hansen. Although they resemble B. davidii, the plants in this series include blood from other species. Buddleja alternifolia and B. globosa both feature in the parentage of ‘Blue Knight’, for example, although this is not immediately obvious.

All reach about 90cm-1.2m (3-4ft) high and wide and develop outward-facing spikes of flowers between 25cm and 35cm (10-14in) in length.

‘Blue Knight’ opens pale lavender purple and matures to deep blue-purple. ‘Dark Dynasty’ has fragrant rich royal purple flowers. ‘Queen of Hearts’ has vibrant magenta red flowers, but with a softness of tone not always seen in flowers of this colour.

You can order Monarch Series buddleias from Mr Fothergills and from Woolmans.

*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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