Question
yes hi i would like to know can i trim flax lillys with trimmers if they are overgrown without them browning or dying?

Answer
HI Billy,
Thanx for your question.  You can always deadhead flowers and remove individual leaves.  Every four or five years, you can chop the whole thing down to within a few inches of the ground to rejuvenate and restore the plant.  Here are some great instructions for pruning and neatening flax lilies.  I hope it helps.
Tom

http://homeguides.sfgate.com/cutting-flax-lilies-back-30299.html