Petasites japonicus – A star or stalker?

Bloom closeup

Fragrant, yellow-white

Peta-what?  Yes, Petasites.  A very cool plant that you will feel is a star or a stalker in your garden.

I came across this plant by way of  neighboring gardeners, down the road a bit.  I walk by their house a few times a week.  The retired couple living there are always tending to their amazing front gardens.  Every time I see them and their gardens, I get more impressed by their dedication and plantings.

Last year, the woman of the household told me she uses Petasites leaves as an imprint in the birdbaths she makes from a concrete mix.  It is the perfect template because the leaves grow up to 2 to 3 feet in width.  And this is what made me notice the birdbath in the first place on her property.  The sheer size of the leaf is very visible on the bowl of her creations.  So I had asked her, what she was using, and at the time, she didn’t know the name of the plant but promised she would show me its growing habit next spring.

So this year, in April, as I was walking by, the homeowners came out to tell me the plant we discussed last year is now blooming in their backyard woodland area.  They explained the aggressive nature of its spreading habit, via a rhizomatous root system.   As we quickly ventured to see the blooms popping up from the ground, it was apparent how many had reproduced from the original plant.  There must have been 50 to 70 of them in the moist, shady woodland area blooming like little alien pods arising from the ground everywhere.  Fortunately, her husband, the more obsessed gardener of the two, has been serving as the body guard of this plant’s reproduction system by removing clumps every season to keep it in line.  What was once a star in their garden quickly became a stalker.

So we all know, this plant is very aggressive, but not technically invasive, thus I gladly accepted the offer to dig up two clumps to put in my container gardens at home.  Here is the photo I took that morning of the clumps.

Petasites root system

Flower clump first, then foliage arises

You see the yellow to white daisy like flowers that came up first in dense groupings, known as corymbs.  And the rhizome like root structure shoots out a leaf a few inches away.  The flowers are fragrant and kind of odd looking.   I wouldn’t classify them as pretty, but everyone’s taste is different.  And the leaves are not super pretty either, but they become dramatically large within a month or so. After a couple days of transplanting my two clumps into two large pots, the plants started to perk up as the roots took hold.

Now, let’s fast forward to June.  The following photos shows how large the leaves have grown.  And as I mentioned, they can reach up to 32” wide.  Super cool for I love foliage more than flowers – not sure why, guess it’s the way this plant’s leaves bob in the wind, reminding me of the tropics, or these in particular remind me of water lilies.  The leaves are very thin, flat and circular in shape.  If they are kissed by the sun, they will droop down and look floppy or wilted, so I pushed the pots even closer to my house facing a northern exposure and they have been super happy ever since in full shade.

Mid June Photo


The area there stays moist and cooler too, so I haven’t had to religiously water the containers; they seem to be happy with a watering every few days.  Also, we have had some rain between our hot days so far this summer.

Leaf Above

Petasites leaf

Upon researching this plant further, it was so appropriate to discover this plant’s Genus name comes from the Greek word petasos.  This means “wide-brimmed hat.”   Of course, I thought – this does look like perfect mold or inspiration for a big showy hat for someone like Princess Kate I would say, fitting as super big flashy hat that only royalty could pull off!  So Kate, do you enjoy gardening?  I say have a hat maker fashion your latest hat statement with Petasites as your inspiration!  Or just grow it in a container as I have done.  Okay, the mind is running away here.  Okay, guess a birdbath will do.

Back to the containers…this plant is a star in my book for containers in the shade or by a water feature.  It grows quickly, is showy, and has no serious disease or insect problems.  But on the downside, it must be kept in check if grown in the ground.  And the leaves are only a plain green, but the veins are slightly pinkish and depending on your point of view, very cool.

On a cultural note, the plant enjoys consistently moist to wet soils in part shade to full shade.  So if you have a full shade location, this plant rocks!  The container can be sunken in mud even, if you want to have a water garden effect.  As I said, the circular shape of the leaves remind me of a water lily.

Early June Photo

June photo

Petasites japonicus is known as butterbur – because, as I read further, the leaves were apparently once used to wrap butter in hot weather. (Hmm, interesting, I thought.)  This plant is also referred to as fuki or sweet coltsfoot.  The petioles (stalk of the leaves) are eaten as a vegetable called fuki in Japan.  In fact, its native range is Korea, China, and Japan where it is found growing on wet stream banks in wooded areas.  The stalks grow long and support the leaves above.  I think the stalks look a bit like rhubarb stalks or stems.  Maybe they are in the same family.  This would require more research.

In summary, this plant serves as a vegetable, water garden plant candidate, will naturalize (so beware of this and keep it only where you can control it, like containers!), and has strange alien-like fragrant flowers in spring, and is easy to grow to huge proportions for a large, very showy, extravagant foliage display – fit for a queen …or princess!  It is hardy to zones 5 to 9 and is an herbaceous perennial.  Eventually the whole plant will reach about 3 feet tall by 5 feet wide.

If you think you would like a few, give me a call.  I know where to get them!  Cathy T

Fall Update to This Post:

October is here and I’ve begun the process of overwintering many tropical like plants from my container gardens.  This being my first experience with growing Petasites japonicus (Zones 5-9) in large containers, I started searching on the web to see if I could find any sources on how to overwinter them  in CT.  Granted, they can survive our zone and are very hardy, but they are too aggressive to grow  in the ground, thus a test in containers evolved this year.  I hope to have them return next season.

The leaves by now started to have lots of holes in them due to a slug or some other nuisance insect feasting on them recently.  Almost all the wide leaves had scattered holes in them.  As I began to cut away most of the foliage and stalks, I noticed a bulb like structure at the base of the plants, all plump and full.  “Interesting,” I thought.  “Another new feature to be curious about on this unusual and large showy foliage plant.”

Fall Photo of Base

My plan is to cover the crown of the bulb-like structures with mulch to provide some insulation, and maybe even a big blanket over the top or around the containers themselves.  Then hope for the best.  That bit of insulation will hopefully recreate the insulation of fall leaves in a forest.  And so long as the mice in my shed don’t try to eat any remnants, all should go according to plan. However, if you find or know of anyone who has tried overwintering these plants in containers in our area, please let me know.  I’d love to hear of their experience to ensure success of my trial.  Cathy T