I bought a little Nepeta Walker's Low last year. It's getting huge! It's supposed to be sterile, but has a lot of seedlings coming up around it that look an awful lot like the nepeta, except they're a different color.
You can see the seedlings to it's left. What are they?
In all fairness, I should mention that another strong posssibility is purple deadnettle. But I compared a blooming one to these seedlings, and it's color isn't quite right, either. Leaf shape is closer, but the color is off for that, too.
How about catnip (Nepeta cataria)? Don't know if it is a common garden weed where you live, but it is here. It would look very similar to Walker's Low, until it blooms anyway.
Thanks. I'm thinking I'm going to let one seedling grow to see what it turns out to be, and cull out the others. I have a feeling it's purple deadnettle (henbit) a common weed.
To update, Judging by scent alone, I think some of these seedlings are definitely nepeta. Now that they're bigger and I can rub leaves enough to pick up scent, some definitely seem to be volunteers from the Walker's Low. The scent on the nepeta is pretty distinctive, even to my crummy sense of smell.
Leaf shape is closer, but the color is off for that, too.
