Pro-mix for me too. I like that I can get the big bales, all year round, at a greenhouse supply place locally. In winter I just bring them in and thaw them. I think I pay about 20 bucks a bale and I go through 3-4 a season. Not all for WSing, but also to fill pots and barrels and transplant houseplants,etc. No weeds ever, perfect drainage, light and fluffy. I mix it up with water and THEN fill my containers. Find that after a good mix and a short "sit" in my big plastic tub, it is a perfect consistancy.

I did something very similar in 2003. Just around thanksgiving with our first snow, I broadcasted out the prairie seeds over a 60x15 prepared area. No mulch, no amendment and the blanket of snow was my protection from birds. Also by this time the mice/voles ect. are housed up for the winter. My seed (flowers/grasses) were individually ordered from reputable native seed suppliers...no walmart mixes just for the simple fact you usually can't find any that do not contain a few non-native noxious/invasive species...like Dames Rocket, Bachelor's Button and Baby's Breath for example; two of which are on our local monitor list and one which made it too the noxious weed list.

missy, I don't think I'd go to the expense or the trouble of something like the 'gritty mix' highlighted at the container forum for winter sowing. Just get a good quality potting medium/mix, you aren't going to be growing long term in it. You do want a light mix that will provide good aeration without compacting while still retaining some moisture. If I'm not familiar with the brands and am at a box store, hopefully there is a broken bag and I can do a handful, squeeze test. Peat or ground bark based are fine....I'd only ditto the 'avoid Hyponex'. I can't get ProMix here, but a local garden supply mixes up the 'Cornell recipe' and bags it for us. I use it a lot. Gardner and Bloome is another local potting medium that's nice. I think the Miracle Grow is available everywhere and while I don't care for it for evergreens/long term container planting, it's been fine when I've winter sown with it too.

I am using pro-mix for professionals that I buy from a greenhouse or a good garden center. To sow regular perennials or annuals, I use only pro-mix but when I sow more delicate plants such as alpine and rock garden plants, I use pro-mix and add grit or small vermiculite, half and half. The mixture allows a perfect drainage and it is easier when comes the time to divide the seedlings and transplant. Sometimes, especially for sowing paeonies, I use only pure sand. Using soil is dangerous as the seedlings will have more tendancy to damp off. If you need more help, you can contact me. Denyse, President of the Quebec Alpine and rock garden Society Here is a link that might be useful: Quebec Alpine and Rock Garden Society