Welcome to NGA,
@subicsteve !
30C is approximately 86F, 35C is about 95F, I believe -- which I don't think is really excessive for tomato plants, as long as they receive plenty of water. As Carol said, you should probably look for "heat tolerant" varieties. I know nothing about volcanic soil, so I totally agree with having a soil test done, if possible; or you could buy a soil test kit that would give you an idea of where you actually stand. Many tomato varieties will grow well in containers, particularly the "dwarf" types and "patio" types, if you have problems growing them in the ground.
