Actually, make that two and a half years… Back in September 2010, I rooted a bunch of lemongrass stalks (purchased from the produce aisle) and planted them in the ground. They were given ample sun, weekly watering in the summer, no (or hardly any) watering in the winter, and quickly grew into something that kinda resembled Cousin It.
That original bundle of three little stalks looks like this now.
And embarrassingly, this is what it looks like most of the year as I’m a pretty lazy pruner. The plant has multiplied into a clump of at least 50 stalks, with the whole thing spanning 4 feet wide by 3 feet high.
I’ve never trimmed it and never divided it, but since the herb doesn’t really get going again until summer, I finally decided to give it a much-needed haircut last week.
In colder climates, lemongrass goes dormant in the winter. The leaves will turn brown and you’ll think the plant has died off. Milder climates (like my zone 10b region) still see a green plant in winter, but the leaves will look a bit bedraggled.
The best time to prune your lemongrass is while it’s dormant, but not until temperatures start to warm up in the spring. Cold-climate gardeners can simply cut back the entire plant to just a couple inches above the tender white part of the stalk, trimming off all the brown leaves.
Gardeners with green plants just need to maintain the shape of the shrub. Light pruning of the leaf tips can be done throughout the year, but a heavy pruning should be done in the spring to give your lemongrass a chance to grow back.
To begin, rake out all the dead leaves under the plant. (If this is your first time pruning, you might be surprised by how much organic matter accumulates under there!) Then put on some gloves (those leaf edges are paper-cut sharp!) and pull out any brown outer stalks as well as brown or rusted leaves. You may have to reach in between the clump to get all the leaves out (but leave the inner stalks intact, as those are the newer ones). I give a light tug and anything dead comes out easily.
Once you’ve removed all the brown bits, use hedge shears to cut back the leaves. I just do a straight cut across and trim a section of leaves at a time.
Trim as much as you want, as lemongrass can take a pretty good pruning. I like to trim my plant into a Tina Turner-esque mound of grass, keeping it funky and clean.
Once you’ve got the shape you want, you can finesse the cut and go all Edwards Scissorhands on it, trimming random brown tips here and there until your OCD wears off.
When finished, you should have a shapely green clump with healthy white stalks.
The arrival of summer will spur your lemongrass to grow vigorously again, and bright green leaves will fill out the plant more.
If you don’t use your lemongrass that often, try to tame the clump by removing wilted outer stalks once a month. Or, you can dig up healthy stalks with the roots intact and replant them elsewhere in your garden. If you’re doing some major dividing on the clump, you can even repot a few stalks to give as gifts!