Solidago- goldenrods, & Stylophorum in PNW
I'm interested in Goldenrods this year, I've seen a lot of people on blogs saying good things about them, and while some spread with rhizomes and can be a little invasive, that appeals to me some since I have 2 acres and am constantly fighting weeds, especially annual grasses that get into my beds. I'm hoping for some good ground covering plants that can shade out the grasses. I would prefer to grow them from seed but if they would be too slow as seedlings and also not blooming until the second year, I'm tempted to buy plants. Has anyone succeeded well with Goldenrods the first year, and which varieties?
I'm also wondering if seed-grown plants must be babied the first winter or can be planted out.
I am also interested in Stylophorum diphyllum, a poppy that makes nice clumps, with the same considerations.