- Thank you for contacting Toronto Master Gardeners.
From your photo I believe you have a Maltese Cross, Silene chalcedonica. The angle of the picture makes it difficult to see the leaf and flower structures. I am attaching a link at the end of the message that shows what the flowers and leaves look like . From that you will be able to tell if I am correct.
Silene chalcedonica is an introduced species originally from Russia . It is a perennial but is short lived and not aggressive. It likes full or partial sun. The leaves of the plant are often fuzzy or hairy. It can often be found in ditches on road sides, open woodlands and areas that have been disturbed.
If this is not a correct ID please try to send a picture which shows more of the details of the leaf and flower.