Q.Monkey grass
The monkey grass that was planted during the summer months leaves seemed to “go limp” soon after our first frost. I have recently noticed the tips of the leaves (stems) of the monkey grass are starting to turn yellow.
Is this normal or is there something we should be doing to maintain the health of the plant?
FYI, we had an extremely dry summer in our area which we watered the plants and they remained healthy. Soon after our first frost, the rains begin and our yard has not dry out before more rain came. Any ideas on what may be the cause of the limp stalks with yellow tips?

If the plant suffered damage from frost you may not have a variety that is hardy enough for your growing zone.
Mondo Grass is hardy in zones 7-11
Liriope or lily turf is hardy 5 - 9
Creeping Lily turf is hardy in zones 4 - 10
The yellowing leaves and poor growing can also be due to the heavy rain and poor drainage. Monkey Grass, no matter the variety, needs well draining soil.