What is this plant?

KazDub

What I thought was a weed growing in a pot has just started to bloom beautiful flowers. I must have planted it and forgotten all about it.
Can anyone identify this?

laros

It looks like a mallow

http://www.gardenbetty.com/2015/04/mallow-the-everywhere-edible-weed/

http://www.wildflowersofireland.net/plant_detail.php?id_flower=158&wildflower=Mallow%20Common

seagull

Bear in mind that a large number of common garden weeds are otherwise known as wild flowers and have really nice flowers, but are badly behaved in a garden. Whether something is a weed or not depends on your perspective.

Sure Why Not

The plant is Mallow, the one person said above.

The full name is Lavatera Rosea (Tree Mallow)

They are lovely, medium-sized, semi-green shrubs. They bloom
continually from early summer to Autumn with a colourful display
of pink flowers. They are fast growing and easy to care for.

They tend to do best in light, moderately fertile soil, well drained, in full sun.
They need shelter for cold, drying winds. In the Spring, hard prune the Mallow
back to 1 ft. to encourage dense growth and to prevent the shrub becoming leggy.

They can be quite short lived. Expect to be replacing the plant after 5 - 6 years.
But the good news is that you can take soft wood cuttings in Spring and have a few
follow-on plants at the ready.