Whilst at the Masterton Farmrs Market I got asked several times how to keep lemongrass (Cymbopogon citratus) alive during winter… Hoo-wee! Old Eketahuna is about 5 degrees colder than Masterton, how cold is it going to get??!
The advice I gave then is the advice I stand by now…
Firstly; if you do live in a place that gets frost/snow consider growing your lemongrass in a pot so you can move it to a more sheltered spot or even inside, during the colder monthes. Remember, this is a tropical plant.
In Foxton it got pretty cold but my lemon grass was in a raised pot and never showed any suffering so the cold wet (ground level) soil is an attribute to possible death. My friend in Paekakariki attributed the survival of her lemon grass (in the ground) by being situated in a place that got morning sun.
Secondly, wherever it is growing, don’t cut the grass/leaves off, allow the frosts to do it’s worst and the leaves will protect the crown. This is not a guarantee though, especially if it’s a particularly heavy frost.
So thirdly; as an insurance act divide the crown…
When you make your next Thai curry (put it n the menu for this week!) instead of cutting the stems you want, look to the sides of your plant and carefully pull a clump of at least three stems from the mother plant. Take it inside and cut the stems off leaving you with a stub at least 3-4cm long.
Sit the stub in a jar of water…within days those stubs will start re-sprouting and roots will start developing. Pot it up when you see fit.