hi Adam - I think what your wife calls poppits are Jewelweed. Their seeds POP if you squeeze the flowers - kinda fun :-)

Anyway, they are GREAT wild plants to attract hummingbirds...hummers love these flowers! I consider that useful!! :-)

If Jewelweed is growing, the area is probably somewhat moist. Thyme generally prefers a well drained soil, even dry soil, so would probably not be a good choice. Ferns would probably do great there. Or you could grow moisture-loving wild grasses which make a great groundcover and provide free seeds for the birds...

Is the area small enough to cover with several layers of newspaper or cardboard and then cover that with mulch? If you can do that and then plant your ferns or other ground cover or shrubs through holes cut into the mulch & cardboard, it will help keep the weeds down until the cover plants get bigger. Exactly how wet is it? Shrubs like some of the native viburnums will grow in dampish areas and will have berries to feed the birds if you have two different cultivars of the same species. Clethra will grow in sun or shade and damp or drier, and have nice, though low-key late summer flowers. Blueberries like good moisture, though not really soggy, and they they will need sufficient sun to fruit. Rhododendron viscosum, swamp rhododendron has small, sweet-smelling spring flowers in white or pink and sometimes nice fall foliage colors; they are deciduous, not evergreen. If it is sunny, cranberries make a nice groundcover. However, none of these are dense enough to block out jewel-weed on their own without the newspaper-mulch layers to discourage the jewelweed (a kind of wild impatiens) all on its own, and you will probably need to weed some plants out even so. The trick is to be sure to do your weeding before the plants bloom and set seed. With no new seed, and your new, other plants getting larger, the weeds will over time decrease in number. My well mulched beds only need weeding for a few minutes a couple of times per year, even though they were created with very weedy horse manure.

You might also try corn gluten meal while you try to establish other plants, if you're planting something that's in pots as opposed to seeding the area. It prevents seeds from growing, so since jewelweed is an annual, you should be able to control it quite well this way. This would be best if the area is not too large, because it's relatively expensive, compared to other types of pre-emergent treatments.

From a random page, at the link below:

"The flowers attract the Ruby-Throated Hummingbird and long-tongued bees, including bumblebees and honeybees. Swallowtail butterflies are less common visitors. ...

"The Jewelweeds have a muciliginous sap that is supposed to soothe skin irritation caused by Poison Ivy and Stinging Nettle. This sap also has fungicidal properties and has been used to treat Athlete's Foot. "

Here is a link that might be useful: jewelweed