What would be a good soil mixture for planting out...

Pre made soil like biobizz all-mix or light-mix are cheap, easy to use and give great results. i have a preference for all-mix wich is enriched and save on nutrients bill along plant lifecycle

You can use the soil there and just mix in some hay and perlite for aeration. Then add some rabbit manure if you can get it. If not than any manure would work. Also some bat guano, fish emulsion, and other organic fertilizers will help boost the plants

fox farm has great soil thats what im using when i transplant mine

If you have a week or more before you are planting I’d get some gypsum into the hole you dig to help start breaking the clay down , then throw in some leaves , bark , wood chips and some charcoal over the top of your gypsum. Then a week or so later fill in the hole with topsoil and worms and blood and bone just follow the instructions. Then feed it with seasol or something similar once the plants are a few weeks adjusted. This is what I’ve done in the past for awesome results and is only anecdotal advice at best .

Amend the soil with coir/peat/compost/manure/tipple 3way mix, no more then 1/3rd of its total volume don't replace it. Line the bottom with a layer of mulch and dead leaves, dig down aorund 3 feet. PS. Quebec Cannabis Seeds are a shady company I would not buy from them again, they steal images from other sites and use them as their own. They have 3 sistering companies with similar names and website layouts. MCS and TCS - Montreal/Toronto Good Luck!