Several summers ago, I came across an incredibly tall perennial, with wiry stems which were covered with tiny lavender-pink flowers. Immediately I loved its airy and open character. Standing at over 2.5m high, this really was the most elegant and delicate perennial I had come across. I looked at the flowers – which resembled tiny hollyhocks. After a little research, the perennial in question was Althaea cannabina , and is a member of the Malvacea family ( and so are hollyhocks )
I really was not expecting to be stopped in my tracks by these flowers ( see images below ) on a very chilly afternoon on Friday December 9th 2022. It really was the perfect way to end to my working week as a gardener.
Common name – Palm-leaf marshmallow or hemp leaved hollyhock
Genus – Althaea
Family – Malvaceae
General information. Althaea cannabina, can reach up to 2-3 m in height.
September 2020 found me growing this plant from seed. The containers were left outside ( as they need cold to germinate) By mid March germination had occurred , and they flowered on short stems in their first year. By the summer of 2022 the same plants reached 2m in height,. It will be interesting to see what height they reach in 2023.
In a sheltered garden they can flower into November ( and December – very sparingly !) in a more open and exposed garden site flowers will last into late autumn , so that is around October.
Owing to their strong and frost resistant stems , I always leave them as structural architectural interest over winter. They won’t be cut back till early spring.
As long as growing conditions are well drained and moisture retentive , Althaea cannabina will grow in full sun or part shade in chalk, clay, loam and sandy soils. And as this description covers the vast majority of garden soil, what are you waiting for ?
Sally Wicks 