DH planted some in deep shade as a ground cover for azaaleas and kalmia. As of this time, they are reasonably happy together, however I do have edging on that bed and I ruthlessly pull up any strays found elsewhere. I use 2-3" wood chips over newspaper as a weed-barrier in that area, so that also helps control the spread.

Actually, I'm not sure how good houttuynia would be as a weed control since I don't see it being thick enough for long enough to act as a shade-control except maybe during the summer. And in my area, weeds seem to grow anytime the temp is above freezing, so I want a year-round barrier.

Thank you for telling me your experience! I think I'll go ahead and leave it for now anyway. I can't seem to get much to grow there. The soil is beautiful, but the deer are ruthless. Vinca is managing, but isn't contrasty enough for my liking, so that puts bishop's weed out too. I use the newspaper trick in my perennial beds, but wanted something to fill and strangle weeds in this area. Any suggestions?

My perennials beds fall into 2 distinct groups: those in partial or nearly-full shade, and those in mostly or full sun. The shade beds are mostly shrubs, hostas, and spring bulbs so every other autumn I spread about 5 sheets of newspaper and top with 2 to 4" of tree chips [nice 1" squares of wood, delivered at no charge by a local treescaping firm]. I also add coarse gravel (in a 6" circle) around the base of each woody shrub to bring that layer back to about 3" deep. I usually do the gravel before the mulch, but I try to be flexible since the mulch delivery comes in at any time. The sunny beds are much more difficult since most of them contain a varied assortment of shrubs, soft perennials, and bulbs; all planted a bit too close :( I have found the easiest way [for me] to do those is to split the job by mulching around the shrubs to the dripline at the same time and in the same way I do the shade beds; and then in the spring I work strips of paper around the just-sprouting soft perennials and top the paper with 3 or 4" of shredded leaves. Some of the softies, like rudbeckia are late to sprout *and* make babies -which I may want- so sometimes I do have to pull a few early-sprouting weeds like violets; but once I've transplanted the new babies, the larger plants get the paper/mulch treatment. By early to mid-summer, most of the various bulbs and the oriental poppies have finished blooming so then they get the shredded leaves-over-newspaper treatment, and I often stab the paper to put annual transplants in. I guess you can figure out that I want something in bloom at all times in those beds.

Obviously, I'm on a maintenance plan now, and no longer fighting big, stubborn, old weeds in any of these beds. However, when I first began, the weeds were horrendous with dandelions that had roots 2" across and halfway to china, lamb's quarters and other weeds that were taller than me, poison ivy everywhere, thistles and briars that seemed able to tear any shirt so as to better scrape my skin. Depending on where I stood in the yard, the soil was mostly sand mixed with clay, or mostly clay mixed with gravel, or mostly just gravel. A lazy gardener's nightmare. I'd be the first to admit that the get-up-and-at-'em gene is nowhere to be found in my bod, however, the keep-it-neat gene is, so the weeds had to go. I can laugh now, but that first summer was a royal battle, with most of the weeds winning. To this day I don't know exactly why I didn't just pull weeds and mulch immediately, but I didn't so I can tell you truly that without mulch, the weeds *will* win and probably sooner than later. A couple basics did finally get through my head: a) don't bother pulling weeds unless the soil is loose enough or wet enough that all their nasty roots come up with the first yank; and b) immediately put down enough mulch to keep the soil in full darkness. Everything else is just a variation on that theme. Using newspaper is a refinement I've been playing with for the past 25+ years, actually one I adapted from padding veg garden paths. By using paper, you can be sure that all light is blocked to the soil so that seeds have trouble sprouting, and you can use a lesser amount of mulch (very important to lazy me). By increasing the number of sheets of paper in the bottommost layer, you actually smother established weeds; the key is to use a thick enough layer of paper to last for at least a full calendar year, by which time the smothered plant has used up all its stored energy and actually dies. A dead weed doesn't have to be pulled. (It also provides nourishment for worms and other good guys, but that's a whole nother chapter.)

Thanks!! All old weeds have been gone for years, it's the strays that wander in... and like you I like it neat! I battled mint and Bishop's weed for 3 summers when we moved in. I finally took a shovel went 2' down and removed every speck by hand. We have a very old home and the crawl space is lower than the flower beds around the foundation so I am very careful to keep the mulch low, therefore lots of paper! or I end up removing dirt like we had to this year about 2 yards worth. I figure if I keep more plants in, there's less room for weeds, but then we have the deer issue. The buggers even munch on the azaleas and rhododendrons, not to mention the nubs of hosta and daylillies they leave in there wake. So, I'll try chameleon plant under the azaleas not connected to other beds.
Thanks again!
Heatheron40