Plant ID: Lavatera?

The other day a coworker and I were walking by a tree pit near where we work and saw a plant that caught our eye. Knowing that he had not planted it, my friend was curious to know what it was and how it got there. The plant stood a few feet tall and maybe two feet wide with a great palmate leaf and smallish pink flowers.
The above picture is a bit blurry (I apologize) but you can see that the flower looks a little bit like a Hibiscus. When you study plant morphology and systematics you learn detailed characteristics specific to different plant families. Seeing this flower I could tell right away it was a member of the Mallow family, Malvaceae. The next time you take a careful look at the ornate center of a Hibiscus flower you will see that the stamen, the male reproductive part of a flower with their anthers and filaments of pollen, wraps completely around the pistil, the female reproductive part of a flower with it's protruding stigma designed to receive pollen. Therefore when I saw this cup-shaped flower an it's unique center ("prominent staminal columns" if you wanna get geeky) I knew it had to be some kind of mallow. But from there we were stuck. I took a few pics with my camera phone and hoped I might be able to figure it out.
So thanks to my reference library and a little down time I was able to learn that there is a great genus of plants in the Malvaceae family called Lavatera. Known mostly as tree mallows the genus includes over 20-25 different species of flowering plants found on every continent except Antarctica. Some are more woody and can get to be large shrubs while others stay smaller and more herbaceous, maintaining softer green branches and stems. One of the latter of the two kinds is Lavatera trimestris, which is what I think this guy might be. Well, that or a close relative or bred cultivar in any event. An easy to grow annual native to the Mediterranean most books describe it as growing three to four feet tall and up to three feet wide, a definite match to this mysterious garden volunteer. Commonly called annual mallow there are a number of different cultivars of L. trimestris these days, all of which have slight variations of these delicate pink flowers. Certainly I could be wrong, but this seems like a pretty logical match and so far is my best guess. Certainly if anyone out there has an opinion one way or another I would love you to comment and share your thoughts.

So then the question is, how did it come to be in this space if my friend didn't plant them there this spring? An interesting thing about a bunch of the European and Asian plants within the Malvaceae is that even though they are hardy to warmer zones and climates I have found that their seed can still sometimes over-winter and survive in the right situation. I first noticed it with a great plant called Abelmoschus manihot, commonly called aibika. Grown in annual displays in a garden where I used to work the curator and I would be amazed over numerous years to see that some of the Abelmoschus seeds that formed in fall and fell across the path into the perennial beds germinated and became their own glorious 5-6 foot plants the following spring and summer. Abelmoschus is only considered hardy in USDA zones 10-12 so here in New York (a Zone 6b or 7a) the plant itself clearly cannot make it through our frozen winters but the seed we assessed must have a tough enough seed coat that in a protected spot they can still germinate when the warmer seasons return. Of course it is perfectly possible that someone else had some of these seeds and broadcast them in this tree pit without us knowing, but now I wonder if perhaps the plant was grown there last year or the year before and this years crop was thanks to some magnificently durable little seeds that were able to tough it out amongst the leaf litter. Or maybe it was grown in a nearby spot and like the Abelmoschus seeds they happen to make their way to this sunny protected spot where the conditions where right for germination this spring. In any event it will be great to continue to monitor this spot and see if the Lavatera comes back again next year, or even migrates to another part of the landscape.

Plants and their determination to grow and thrive even in challenging climates, fascinating and inspiring on so many levels.