I have found that Rose-of-Sharon, H. syriacus, can self-sow to the point of being a problem. Perhaps certain varieties are worse than others.

OP is talking about perennials. The responder is talking about the shrub. The problem with common names again.

Sorry Dave, two of the varieties you list are tropical (H. rosa-sinensis), the one 'Moy Grande' is a hybrid based on some of the perennial species.

In any case, as for any being invasive in this part of the continent, see my first post. ;) And even then, it's only more of a nuisance.

OMG...

are you talking about mallow?? ... lol.. another common name????

let me put it to you this way ....

i bought a 2 inch pot at hidden lakes [one of many bad plants they sold] ....

within 3 years.. i covered a 10 foot square area ... and i went after it with roundup ..

and 5 years later... they are still sprouting ...

i hate them them with a passion equivalent to the white hot heat of the sun ...

and for a shiny penny.. i will tell you how i really feel .. lol

though i cant say they escaped that bed ...

ken

Ken, are you referring to Malva sylvestris?

I have no clue what the OP is talking about re: shrub vs. perennial, but want to chime in and say I do not find H. moscheutos invasive.

hmmm.... now I see that one packet was labelled "Rose of Sharon Hibiscus - annual - self sows)." Maybe the person who gave me the seeds was trying to warn....

I think I am going to try some and be careful about the seed pods.

I knew there were annual and perennial hibiscus, but I didn't know shrub is another category. I have seen some nice shrub hibiscus in my neighborhood. Are those hibiscus or malva?

I've never found any of the perennial hardy hibiscus to be invasive either by vegetative growth habit or self-seeding, in any climate in which I've grown them, from Gulf Coast zone 8b to current zone 6a. This includes H. moscheutos hybrids and native species which are hardy well up into the Midwest and Northeast such as H. militaris/laevis (halberd-leaf Hibiscus), a generally white or pink-flowered variety (mine is pure white) which blooms much of the summer here and has remained a small patch in an unmulched front bed for the last half-dozen years or so.

There are a number of hardy Hibiscus species worth trying in the perennial garden (another is H. coccineus); their only real drawback as far as I'm concerned is they are often highly attractive to Japanese beetles. H. moscheutos in particular is apparently almost as tasty as roses.

'Rose of Sharon' is the common name usually applied to a deciduous shrub form of Hibiscus, Hibiscus syriacus (also to Hypericum, but that's another issue). There is some biblical association with this plant (native to parts of the Holy Land/Syria), hence the common name. It is a very commonly planted flowering shrub but can self-sow rather freely in some areas, hence the cautions about potential invasive properties.

Annual species of Hibiscus are not typically referred to in this manner but with common names, anything goes :-) Often you will see these called 'rose mallow', 'swamp mallow' or in one case, 'Confederate rose mallow'. And I agree that these are not known to be invasive.

Common names ARE confusing....no way around it! It would have been far more helpful if the seed provider had taken the time or effort to label the seeds with both parts of the botanical name, genus AND species, but at least the cultivar names can provide some direction. Personally, I would be very cautious about purchasing or trading for any plant or seed that was only identified by common name or partial botanical name. Without the full botanical name, you just have no idea what you are getting. And even that can be suspect at times -- know your supplier!!

Here is a link that might be useful: rose of Sharon mythology

dave...

its NEVER a problem to try anything ...

and then you work toward a full and proper ID ... pix here would achieve such ..

and then you research to fully understand what you have.. and where it is going ... and you try to accomplish this.. BEFORE IT SETS SEED ... lol ..

then you either leave it.. or destroy it ..

i doubt there is ever any harm in trying... the harm comes in forgetting about it.. for 2 or 3 years.. lol

ken

That was a very interesting article you linked, gardengal, on the mythology of Rose of Sharon. I have always wondered about the name. I don't grow it, but a neighbor has a lot of them. Decades ago I studied the religions of the ancient near east; I will save and study this more later.

i doubt there is ever any harm in trying... the harm comes in forgetting about it.. for 2 or 3 years.. lol

errr.... that harm already came. Some of my hibiscus seeds are labelled 2007, but I am going to give them a try anyway.

Perrenial deciduos hibiscus (can't tell you which) can be quite invasive. I got rid of mine over five years ago and each year new ones still pop up all over.

The Japanese bettle problem is easy to fix -- at least locally. Milky spore. Years ago I put it down several years in a row and now it is extremely rare to see even one beetle. As long as there is food, i.e. larvae, the milky spore will thrive and spread. My neighbors. My neighbors are very happy.

I need to try milky spore. Do you have to buy it online, or do garden centers carry it? Thanks

Most garden centers carry milky spore I believe, although they may only carry it seasonally, i.e. spring and summer. Otherwise you can get it online. I often source items from Gardens Alive.

Opportunity: (past observations) + (reading this thread) + (additional reading) = (enlightenment).

I have to occasionally deal with shrubs; namely in this instance, Hibiscus syriacus (Rose of Sharon). Have had a single-flowered one in our own garden for years and it's never seeded.

Put a double-flowered cultivar in a garden and was too busy to deadhead it one year. I'd been deadheading it because the spent blooms seemed so ugly. The next year that plant had seeded all around itself and on into the lawn and I needed to pull up over a hundred Hibiscus seedlings.

More recently I'd salvaged a double-flowered Rose of Sharon (cultivar 'Lucy') and put it in our own garden. I now had two reasons to deadhead 'Lucy'; namely, still don't like the ugly spent blooms and the suspicion that the cultivar could be an invasive self-seeder.

Posts above pushed me to look up 'Lucy' on-line. Just read a warning about it; namely to deadhead its spent blooms to stop it being invasive.

In fact, it was the confusion around the common name "hibiscus" that presented me with an opportunity to become enlightened on this matter.