i will make it as simple as i can.. its for you to take the bullet points and go from there ... heres how you do it... use google.. find out how long from planting to bloom ... lets say 90 days ... then work back from there.. you want them in july ... they should be planted 90 days back ... or may ... you want them in august ... plant in .. etc ... [did i count right.. lol ] the problem is.. that every single one will bloom in one week.. which is nice .. but if you want a bigger/longer show... you plant some every week in may ... so you get a month of show ... if you want them in late august.. plant them in june .. got that part?? ... if not i can try again ... let me know ... now... as with ALL SEEDS .. or in this case corms.. soil temps are imperative.. frankly.. you MIGHT be too early ... soil temps might be warm during the day.. but if it is often falling into the 40's at night .. you dont have the constant soil temps to start the growth.. the seeds wont die ... but they arent going to sprout until some magic temp number is hit.. which in my z5.. wont be for 2 or 3 more weeks ... like when it stays in the 60''s all night long ... most likely all chances of FREEZE.. as compared to frost.. are gone.. so we need not worry about freezing the corms ... then in our zones.. you really dont want them getting too big.. until all frost possibilities are gone... and for me that is late may ... you.. maybe a week sooner .. so are you late... ABSOLUTELY NOT FOR YOUR ZONE .. and you may be too early by a long shot ... shall i try again.. i am willing.. ken ps: i have lived 100 miles south of flint my entire life.. no glad is hardy .... UNLESS they are planted along the house.. where there might be a micro climate .. otherwise.. i would like to get some of those corms for my garden .... and maybe get them to market .... pps: you could take an old tray.. put some damp media in it.. and loosely cover the corm .... and start forcing growth .... in the garage .... and when the growth points get an inch or two big.. go plant them out in the soil .... and maybe get them to bloom a few weeks earlier ... try it with 3 or 4 ... experimenting is the BEST way to learn ... just dont forget about them.. and find them in august.. lol ...

Here glads produce the tiny cormels (baby plants) and end up being a forest of tiny clumps of foliage, a real weedy mess. This might not occur in your colder zone. I have also read that they are breeding grounds for thrips, but I cannot remember the source of that idea. A thick organic mulch, renewed every once in a while, is better than weedcloth over the long haul--the mulch continually breaks down, enriching the soil and making it easier and easier to work. Over time, as Michael said, the weed cloth produces problems of its own making.

Go ahead and plant them in a sunny location, but keep them watered. The leaves may die back, but don't despair. Mulch them for the winter, but in your location they probably will be OK. Mine in 7a (piedmont NC) live through the winter (though they are dormant -- die back completely) but I mulch them well with shredded leaves. usually bulbs are planted in spring, but in your location its safer to get them in the ground. For the one without a bulb, compost the leaves; you have to have a bulb to get a new plant, and it's not a stupid question.

Back in the year one when I was in zone 2 and knew even less about gardening than I do now I planted petunias around glads. Still plant a few petunias for old times sake but have given up on glads. Too time consuming and need dusting for insects. They are a lovely flower tho and I remember cutting them for bouquets from my parents zone 8ish garden. Lady's Mantel is another possibility. It's one of my fav plants so I'll suggest it for almost any application! ;-) Feverfew is another good plant for covering ground. It's a real weed altho in my zone I find it very useful. Easy to pull so not invasive and if you deadhead it's fine. Very prolific self-seeder tho.