Orange petals also help with the hiding. If you're using the petals, the poison trap usually won't reveal you. So, you only have to trip the explosion and/or dart (some chests seem to have 2 traps, but most all 3).
The strategy also works with the puzzle chests, which only hit you with one trap per failed combination, but remember the hide timer, and that the puzzle chests reveal you when you click to start trying. So, you go slow. Be hidden, wait for the timer to run 9 seconds before opening the chest to get to the combination lock, and then hide immediately on the reveal. Work on the combination, but again take long enough before entering the combination so that you will be able to hide if the trap is one of the damaging 2 instead of the poison. repeat as necessary. However, you can't really use it on the chests in the tentacle area or spawn area when active (the first from the regular damage, the second from there being too many spawn - one WILL see you)