Rose mallow hibiscus

(Question)

Hello, I live in Sarnia, Ontario. I purchased the above plant last year and read online that it needs to be cut back to 12″ above ground in the late fall which I did, however it is slow to grow this spring. Is it necessary to cut it back, I would like it to get and stay large every year.

(Answer)

Rose mallow hibiscus (Hibiscus moscheutos) is a perennial native to North America. It thrives in moist and slightly alkaline soil and blooms from July to September. Keeping rose mallow well watered will help to encourage flowering. The flowers grow on new wood – that’s why pruning down your hibiscus in the fall or spring and continuing to dead head through the summer will provide you with many flowers through the growing season.

Rose mallow is often slow to emerge from dormancy in the spring and this spring has been a cool and dry one which may explain the extra slow emergence. It will die back to the ground each winter regardless, therefore you won’t see the bush remain large though the year.

If all the growing conditions are met you should have a 3-6ft bush by the end of the season.

For further reading please see the following links:

https://www.wildflower.org/plants/result.php?id_plant=HIMO

https://www.finegardening.com/common-rose-mallow-hibiscus-moscheutos-and-cvs

https://www.torontomastergardeners.ca/index.php/askagardener/hibiscus-moscheutos/