Prostanthera rotundifolia, “mint bush” Plant of the Month April 2021

I love annuals.  I love perennials.  Here’s a plant that’s somewhere in-between, a short-lived perennial:  ‘Bowles’ Mauve’ wallflower, known botanically as Erysimum bicolor ‘Bowles’ Mauve’ (sometimes listed as E. linifolium ‘Bowles’ Mauve’).  Yes, the apostrophe situation on this one is weird. Cultivars usually have a single apostrophe at the beginning and end (‘Orange Jubilee’ for example), but this one has a possessive apostrophe in the middle (it was originally found in Edward Bowles’ garden in the UK, hence the name).  This woody shrubby perennial has handsome gray-green evergreen leaves, multiple branches, and spires of mauve-lavender-purple flowers for month after month after month, starting in late winter (March, locally) and going non-stop until the height of summer, then resuming with a smaller, but still pretty, display in autumn.  A plant that is several years old will have dozens and dozens of stems, each with a stalk of flowers that open from the bottom up.  The flowers open a medium purple and fade to a light mauve, creating a nice bi-color effect.  The pretty flowers are barely scented, but they compensate for that by appearing in great numbers.  A large plant will be several feet across. The only real maintenance is to trim off the long wands of flower stalks after they have faded.  Given full sun and water only when pretty dry (go extra light on summer water), they’ll provide 3-8 years of easy enjoyment.  They’re easy to propagate from stem cuttings, so you can always have replacements handy, or extras to share.  If you haven’t given them a try, I hope you will.  If you do, let me know what you think.


Contributed by member/club President (2020-2022) Grant Meyer