• 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

'Black Truffle': a superb new dark-leaved perennial lobelia

Colourful and very hardy, 'Black Truffle' knocks the socks off older lobelia cultivars

There are two perennial lobelias that we seem to have been growing for centuries – and judging by their names, we probably have. ‘Bees’ Flame’ (named for a long defunct nursery) and ‘Queen Victoria’ both have bronzed foliage and scarlet flowers. Both have been often raised from seed, and many seedlings with poorly coloured leaves have been sold and passed around. The result is that many plants sold with these names, instead of dark bronze or shining reddish purple leaves, have green leaves tinted with bronze. You never quite know what you’re going to get.

The glorious dark rosette of Lobelia cardinalis 'Black Truffle'Now we have a new lobelia in a similar style, but the leaves are guaranteed an extraordinary rich colour and combine well with the vivid red flowers.

The new foliage of ‘Black Truffle’, which makes a rosette in spring, is as close to black as you will get – except for the vivid purple-red highlights. Then, as the plant develops and the stem extends, both stem and foliage take on a slightly coppery, shiny maroon colouring. Finally in summer, after months as an outstanding foliage plant, the spikes of scarlet flowers open as the climax to the display.

Lobelia cardinalis 'Black Truffle' with its spikes of scarlet flowers.‘Black Truffle’ is never grown from seed, so its rich foliage colour is guaranteed. It was discovered by American native plant specialist Peter Heus amongst a batch of Lobelia cardinalis seedlings on his nursery in West Virginia.

This is a very hardy perennial, it will take winter temperatures down to almost -40°C (-40°F), but appreciates moist soil and plenty of sun.

Lobelia cardinalis ‘Black Truffle’ is available from Beeches Nursery and from Premium Perennials.

One thing to note: although this plant has initially been listed by nurseries as 'Black Truffle', it looks as if the correct name is going to be 'Chocolate Truffle' and it will be listed as 'Chocolate Truffle' in the future.

** Please note the contents of this blog reflect the views of its author and are not necessarily those of the RHS **


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