[TS]

Lirazr, I usually use 1peat:1perlite, or 1 sphagnum:1perlite for VFTs.
Normally I just pot it up and place at a bright (no direct sun) place for 2 to 3 days, then tranfer it to full sunlight, VFTs love sunlight. But what I worry is the summer sun in your country, how hot do you mean "heavy summer"? In Malaysia the hottest day could just 36 or 37°C, more then that I think your VFT will get cooked.
If you place it in terarium, humidity don't have to be too high, VFTs don't require high humidity to thrive. But lighting yes, need very high light intensity to grow well in terarium.