[MargeSimpson]

I had to pull up a couple of hollyhock plants today as I typically planted them in the wrong place. I seem to have done that alot this year. But I reckon by mistakes we learn. Anyway...I have never seen roots like them!!! They are incredible. I had a job pulling them out. Are Hollyhock (Alcea rosea) best planted in pots to contain the root. Do they tend to run and take over like nastursiums?

[Sb]

Yes, I found that the hollyhocks had very strong sinewy root as well, MargeSimpson. Never had any problem with them spreading though.

[GPI]

Sb is right marge, you should have no problem with hollyhocks invasively spreading by roots.
Those roots are tough though, they are famously used in tibetan medicine, where the roots on their own are used to treat loss of appetite.

I think you will find that the hollyhock spreads far more agressively via seeds.

[Tessa]

Hollyhocks are one of my favorite flowers and the mainstay of many southern gardens. Most plant them against houses or fences so they don't blow over. I have found many still blooming at old long-abandoned homesteads over a hundred years old. You can bet I snagged some seed to keep that tradition going.

There is apparently a perennial hollyhock, but most of them that I know are biennial. They do reseed, but I've never found them to be invasive at all. Just lovely, and the hummingbirds just love them.

Anyone know anything about the perennial one?