Hey Star...

Yeah, you can grow two strains....

But I'll give you my take on it...
I started my grow, and had various strains to pick from... but, I choose only one.
Why?
Well, you can grow them... but it's going to be a pain in the ass when the different strains grow at different rates... when they react differently to the nutrients... when one is taller than the other (what to do with the light!)... or when one is ready to cut down but the other one isn't yet.

You can do it... I don't see why not. But it'll require just a little bit of extra effort. But hey! Go for it!

,

-turtle420