Mirabilis, perhaps?

Here is a link that might be useful: M. jalapa

Yep, that's it - thank you so much!

Fascinating how the previous owners planted all these invasive species... I think I'm going to have to kill the whole garden and start over next year. :-( Not a small task - it's about 20 x 30. Sigh.

It has a tuber that you'll have to dig up, too.

It may not be perennial where she is; it sure isn't in zone 6, and some websites say that it's not reliably hardy outside zone 8, so she may be dealing with self-seeded plants rather than plants that just won't die.

True, not reliably hardy in the lower zones, but this plant is famous for finding a micro-climate and sticking around, even in z5. If you do find large tubers, although you may not want this plant, that's an indicator of a spot where you can experiment with some zone-pushing.

it looks like 4 o'clocks to me. does it have little black hard seeds as the flowers fad?
4 o'clocks come in lots of different colors, will seed it's self as those little black seeds drop, but will come back from long heavy roots.

It does have very dark - what I called purple - berries. I believe it is self-seeding. I bought the house in March, so I'm assuming the previous owners did the planting last year or before. I think it's acting like a perennial, at least right now - we had an extremely mild winter last year, and this garden gets full sun all day, so there could also be some micro-climate going on. The garden is also full of huge chunks of limestone, which is also throughout the yard. In fact, the whole house could be built on limestone for all I know.

I would rather turn this 20x30 space into a low-maintenance rock garden. Here's the strategy I was thinking of: once we have our first freeze, weed-eat everything down to nothing, dig up the tubers and everything else, maybe (or not - your opinions, please??) spray the whole thing with Killz-All, cover with black plastic, and leave till next summer at least.

This garden is full of "junk" - invasive species, weeds galore, weedy vines, the remnants of a japanese maple, but also some nice ground covers. I was going to relocate the ground covers to other needy spots in my landscape, and eradicate everything else. I'm a working girl, don't have the time or inclination (or money) for a high-maintenance landscape, was completely surprised when all this stuff started sprouting, etc. etc.

If anyone wants any invasive species tubers/cuttings, let me know!

Everything before 'cover with plastic and leave until next summer' would be unnecessary except to reduce the bulk by mowing or weed-wacking, so the plastic lays flat. Cardboard also works and does not need to be removed later, a plan I prefer since you never know what seeds are going to sprout after you remove a smother barrier. This also allows the weed material to decompose and help improve the soil with very little effort on your part. You can cover the cardboard with mulch so it's not ugly and stays in place. When you get a gardening urge next year, install some plants.

Shrubs are the easiest to deal with when one doesn't have much time to spend. As long as they're not eventually too big for the spot, most can be a "plant it and forget it" plant that only needs occasional trimming for structure and dead twigs or branches. They will shade the ground around them so weeds are less likely to sprout, and it's easy to add new mulch around them as the old become thin enough to allow weeds to grow, and/or to add a new smother layer if something does creep into the area.

Low maintenance and rock garden are not necessarily married. Do you mean a rock mulch? Whatever seeds find their way to that are just as likely to sprout, but harder to pull out, especially tree sprouts.

Whatever you don't like, you're right to say it should go. You don't have to know what you want to eventually do to get started wiping the slate clean.

Thanks, purple! It just so happens that I have quite a bit of cardboard (moving will do that...). I would much rather not do a mass Kills-All if I don't have to, so I like that plan.

The reason I say rock garden is that half of the plot is big hunks of limestone. I was thinking I'd just fill in the gaps with river stone and maybe a few choice plantings. Anyway, first things first - get rid of what's there. That'll be a big project in and of itself.

Thank you so much for your help identifying my plants and advice on how to handle this space. I love GardenWeb! --Lesley