What is this weed and how can I kill it?

Question

I'm having a hard time identifying the weed pictured below. I live in southwest Connecticut.

I have a smallish flat area behind my house where this was rampant. I dug up all of it that I could find, turned over all the soil and planted new grass. Since then, the weeds have come back up.

I should also mention they flower bluish-purple in the spring.

There's quite a bit of it and it spreads fast, so I'm hoping there's a topical treatment or something I can use to get rid of it. I've been pulling it by hand but it keeps coming back.

Answer 1

The leaves look like violets especially if they flower purple, white, or yellow. I have a bunch in my yard and they usually grow in full to partial shade.

Wikipedia Link to the genus Viola for more information and variations

Answer 2

Updated answer after question was edited to state that the flowers are bluish purple: This is not garlic mustard, which has white flowers. It does not look like any violets I've seen, and not exactly like the creeping charlie we have here either. Sorry I am not able to help after all.

Previous answwer: This looks an awful lot like garlic-mustard, which we also have here in the Fingerlakes region of NY. It is a noxious weed and hard to eradicate. I have had some luck pulling it up, but it's a constant battle. The real key is keeping it from going to seed, which happens during the 2nd year. If you can hand pull the 1st year plants (make sure you get all of the root), they won't go to seed, but it sounds like you probably have a bunch of seeds already in your soil, so you'll be pulling plants from the old seeds for a while :(

Here's a link to a WA state website I found with photos & info that may be helpful to you. http://www.kingcounty.gov/environment/animalsAndPlants/noxious-weeds/weed-identification/garlic-mustard.aspx

If you look at the photos there and think this is what you have, you can search for other methods of control if hand pulling is not practical.

Answer 3

We call it Creeping Charlie here. I pull it up by hand when it gets out of control in the garden, it comes out very easily. Usually it grows in the shadier parts of the yard with poorer soil and I leave it because I like the purple flowers in the spring. It also makes a good ground cover on a hillside where it is difficult to mow.