Here’s the Acanthus sennii that Loree picked up for me at the HPSO spring sale. She could not resist getting one for herself too, and writes about it here. I was amazed by how carefully she studied her plant to observe its behavior throughout the day.
I have very little to add, except that mine did bloom. The bright orangey-red of the petals came as a surprise, and the flower form is different from other Acanthus.
The tall spires of Acanthus spinosa are more representative. They are also longer lasting, drying in place as a dramatic focal point with the large spiky leaves turning autumnal colors by early September.
The smoother leaves of Acanthus mollis are huge. Here in the woodland it is too shaded for them to produce flowers.
But where there is more sun, they produce flower spikes that are more subdued than those of spinosa, whose leaves in the foreground are hiding the smooth mollis foliage.
Planted in mid-March, Acanthus syriacus has yet to reveal its true nature, but the leaves are spiny and the flowering stalk reaches only about a foot. It was not very attractive, so I cut it off as soon as it was finished blooming. So I have several, but with 30 species in the family I have a long ways to go before I could claim to have a “collection” of Acanthus.
Which brings us back to Acanthus sennii, which has put on quite a bit of new growth since it finished blooming. I had tried this once before without success. Moral of story: buy from a good grower…or maybe, just keep trying until you luck out matching plant to place. Here’s a link to Loree’s most recent favorite.