Bamboo is a sustainable fiber, and does not depend on oil as most synthetic fibers do. Mattresses that use natural bamboo fiber covers include Englander and Symbol, but there may be more. Simply check out the cover material as opposed to the materials used in the interior layers of the mattress that wrap the spring unit.
Innersprings and Pocketed Springs. With innerspring mattresses, the springs are joined together, so that when one is compressed, its neighbors are also compressed because they are joined. That then affects your partner sleeping beside you. In some cases, this effect can be minimized by alternating the coiling of the springs, but not eliminated.