Local Soil is Red Clay.. Grow bags, pots, what?

I am going to attempt my first grow this April/May. I have 5 feminized Holland's Hope (I have been told it is very easy to grow), 10 Cheese and 10 Train Wreck (these came free). I will be planting in multiple patches and will not be planting all of the regular seeds (or in the same patch(es) as the feminized seeds). In total I will be planting around 10-15 plants, not because I think I'm going to be racking in a huge ass crop, but because the greater odds I will get at least something.

I live in the Pacific North West in the boondocks and here the soil has lots of clay in it. I am curious to know if putting my plants in grow bags would be a good idea, or even digging a hole and then filling it with something like Fox Farms Ocean Forest. Or is there an alternative solution that would work better?

How would this effect my yield? Would it work? Which would be the better option? Also would I use just the prepackaged soil, or would it be necessary to add something to it?

I know this would involve a lot of digging, but I am a young and in good shape so I think it isn't anything I couldn't handle over a few weeks between March and my plant time. I would like to do everything possible to make this grow as big of a success as a 1st time grow can be (which probably means getting any amount of weed haha).

Thanks for any help in advance.

Would it work to do 50% FF or similar organic soil and 50% dirt (or at least a cheapo soil like pro-mix)?

FF is pretty cheap where I live compared to prices I have seen quoted else where ($13 vs $20) but a single bag is only 1.5cubic feet, the cost of soil adds up pretty quickly.

Go to Home Depot get you some Patio plus. It will cost you less for soil. I think you have a plan be safe and Good Luck.