Lemon grass - Cymbopogon citratus

I have a total of 5 tufts of lemongrass growing in my garden. So far they are doing very well. They grow to become this big tuft of grass-looking bush. They are certainly better than grass because they can be eaten. I have not harvested any yet as the stems are still thin. I surely cannot imagine how they will look like when their stems become as thick as those in the markets. This is the first tuft (at Patch C) and their stems are getting thicker : And this is the second tuft in Patch E :

And three tufts side by side on the front garden :

I hope they can survive the winter as this is my first time having them since spring. Yesterday morning I had to pluck all four of my last bitter melons and throw them out as they were frost-bitten. I did not expect the frost in autumn. Will have to protect delicate tropical fruits the next season.