Butterfly weed may not survive in clay soil, it requires a very well drained sandy soil.

Sage and gayfeather also prefer well drained soil but may survive. Purple coneflower is the most tolerant of clay but needs good drainage and does not like to be wet during the winter.

All except purple coneflower need full sun; purple coneflower can take a little shade. Check out the fence and shed to make sure they are not casting shade on the area where you intend to plant.

Adding a layer of soil on top of clay is not advised as the clay will block water and the soil above may become soggy. The best way to amend clay is to add 6-8 inches of compost and dig into the clay to a depth of 18 to 24 inches. You will need to mulch with more compost every other year. Some people advise adding up to 1/3 the volume of compost in pea gravel or coarse sand as well to improve the drainage.

Seeds will need moist, cold stratification. This means planting them into seed trays, lightly watering, then cover with plastic and store in the fridge for 60 to 90 days. They will germinate when brought back into the warm.
If you don't have room in the fridge for seed trays, then fold a paper towel in quarters, wet it and wring it out. Open up one layer, sprinkle on the seeds and fold back over. Place the moist, folded, seeded paper towel in a baggie or ziplock bag, seal and store in the fridge for 60-90 days. Remove from the fridge, sow seeds in seed tray or directly into the ground. You should get germination this year, but will not likely see flowers until next year or the year after.

Thank you Judy!
Terrific advice:)

Jennifer, it actually depends on the type of butterfly weed that you have. Is it asclepias tuberosa, asclepias incarnata, asclepias syriaca, speciosa, viridis, verticillata, there are so many different types. However, the most commonly sold on the market is A. tuberosa (perennial and has orange flowers). As the name suggests it is tuberous rooted, as most milkweed tends to be.

In that case, there are actually two different types of tuberosa, one that grows well in clay soil, and one that does not. Of course, I would suggest mixing in some compost and manure anyway. Let me know if you are interested in further details.

Gayfeather, or liatris, is a tuberous plant as well, so growing it from seed will probably take at least 2 years if not more before it flowers. Pitcher's sage and Purple Coneflower (echinacea), will probably flower the first year from seed, or if not, the second. Both will seed around once they are large enough to flower. Mine do.

Since these are native plants, they will probably adapt to your conditions if they are native in your area. But, I would get them started in little pots first, and then transplant them. Transplant the milkweed quickly after it has a few true leaves, because they dislike transplanting. Or, grow them in paper towel tubes cut into thirds and filled with potting soil. Then you can plant the little cardboard pot and all. You can fit several in the bottom portion of a milk jug (put drainage holes in the jug).

You would probably be better off purchasing a bag of Liatris tubers at Home Depot or Wal-mart. I got a bag of 25 tubers from Wal-mart for about $5. Pretty cheap.

Have fun!

Susan

I'm not a specialist on growing wildflowers but I learned a lot about recognizing wildflowers in the forests and fields.
It's a favorite passtime of mine once the winter is finally gone, I'm getting my daughter involved as well, she now recognizes a few wildflowers and trees.
I put a page together with a few pictures of wilflowers and their names and what's unique about them, it's a great page for kids to learn or anyone else interested.

Here is a link that might be useful: site map, wildflowers

I thought I was going to see photos of wildflowers?

Jennifer, This question really offends me. Stop clogging up the internet with this sort of ignorant, ill-conceived drivel...oh, wait, you asked for POLITE advice...

Seriously, I think the four species you bought are all pretty adaptable and should do fine in most soils, even if the soil has a lot of clay, just as long as your fence line isn't too marshy or too shady. I definitely wouldn't add a thin layer of soil on top of the existing soil. I would probably just dig or till the existing soil, remove pieces of sod or weeds to stop them from sprouting, and sow your seeds. If you want you might mix in some organic matter (such as compost) with the existing soil, but I don't think that is necessary in most soils. While you're clearing a spot for the flowers, clear a wide border as well. I try to have at least a foot-wide border cleared because seeds take time to fill in, and the border holds the existing weeds or grass at bay for a while. I think it is better to grow wildflowers in the existing soil rather than try to add a layer of imported soil. Wildflowers grown in the natural soil seem more inclined to root deeply, while those in a layer of imported soil sometimes seem to grow roots only in the imported soil and not develop healthy, deep roots.

All of your plants require a fair bit of sunshine, so be careful which side of the shed you plant them on. There may be one or two sides of the shed that are too shady even if the shed sits in the open.

If you have shade or marshy areas you can still grow lots of nice wildflowers, but you'll need to select different species.

Keep your flowers weeded during the first year or two. After that, once they are established and growing strongly, they will not require much attention. They will compete strongly with any weeds that come along and should be OK with just the occasional weeding and removal of woody vegetation that might spring up.

Good Luck!

rachelneil, your link says

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