Lemongrass needs two kinds of cutting each year: light tidying in summer and one hard cutback in late winter or early spring.
To trim lemongrass, pull or snip off brown leaves as they show up, and once a year, just before new growth starts, cut the whole clump down to about 6 to 12 inches above the soil.
Pots headed indoors for winter get their own trim, down to about 6 inches, before nights drop below 50°F. Get the timing right and Cymbopogon citratus (the West Indian lemongrass you cook with) bounces back fast.
Get it wrong, and a cold snap or a bad summer haircut can set the plant back for weeks.
Why Trim a Lemongrass Clump?
Trimming keeps a lemongrass clump healthy, a manageable size, and easy to harvest. In warm weather with plenty of sun, water, and food, a clump can reach 4 to 6 feet tall and nearly as wide. If you are stocking up, a pair of bypass pruners is the first thing I would pick up.
Pruning lemongrass solves a few specific problems:
- Dead leaf buildup. Brown sheaths pile up at the base, trap moisture, and make it hard to reach the good stalks.
- Crowded centers. Dense clumps hold damp air in the middle, which invites rot and fungal spots.
- Tired growth. Cutting back old foliage pushes the plant to send up fresh, tender shoots with better flavor.
- Sprawl. A big clump flops onto paths, chairs, and neighboring plants.
I think of trimming as part of regular care, right alongside water, sun, and feeding. My lemongrass care guide covers those basics if your plant needs more than a haircut.
One safety note: the ASPCA lists lemon grass as toxic to cats, dogs, and horses, mainly causing stomach upset. Keep piles of trimmings away from pets that like to chew grass.
When Should You Trim Throughout the Year?
Lemongrass plants get small cleanups all summer, one hard cut as winter ends, and a protective trim before frost in cold regions. Your USDA zone decides which of those cuts you’ll make.
What Calls for a Light Summer Trim?
Summer is the season for small jobs. Lemongrass grows fastest when days are hot and nights stay above 60°F, so it can handle regular tidying.
Trim in summer when you see:
- Brown or yellow leaves at the outer edge of the clump
- Dry, crispy leaf tips
- Leaves bending into walkways
- Stalks ready for the kitchen
A quick pass every 6 to 8 weeks keeps most clumps looking neat. You don’t need to cut it every time you walk by.
When Is a Hard Spring Cutback Safe?
The hard cutback is safe once the worst cold is behind you and before new shoots start pushing up. In most of the warm US, that falls between late February and April.
Watch for two signs. The danger of frost has passed for your area, and you can see a hint of green at the base of the clump. Cutting at that point lets the plant put its energy straight into fresh growth.
How Does Your Winter Climate Change the Timing?
Lemongrass is a tropical perennial grass, hardy only in USDA zones 10 to 11, and zone 9 with some protection. Where you live changes the plan.
| Your area | What to do |
|---|---|
| Zones 10 to 11 (South Florida, coastal Southern California, Hawaii) | Tidy year-round; hard cut in late winter |
| Zone 9 (Gulf Coast, parts of Texas and Arizona) | Leave foliage on through winter for insulation; hard cut after last frost |
| Zone 8 and colder (Midwest, Northeast, Pacific Northwest) | Grow in pots; trim to 6 inches and bring inside before nights fall below 50°F |
In zone 9, I’d leave the dead winter leaves standing until spring. They shield the crown from the occasional freeze.
Tools and Safety Before You Cut
Good tools and gloves make this a ten-minute job. Lemongrass looks soft, but its stalks are tough and its leaf edges are sharp.
Choose Clean, Sharp Pruning Shears
Bypass pruning shears are my top pick for lemongrass. They slice through thick stalks with one squeeze and leave a clean cut that heals fast.
For a big, overgrown clump, a hedge trimmer or a serrated knife works for the hard spring cut. Kitchen scissors handle leaf tips and a few stalks for dinner.
Before you start:
- Wipe the blades with rubbing alcohol or a 10% bleach solution.
- Sharpen dull blades. Dull shears crush stalks and leave ragged ends.
- Wipe the blades again between plants if one clump shows spots or rot.
Wear Gardening Gloves for Sharp Leaf Edges
Lemongrass leaves have fine, saw-like edges that leave paper-cut style scratches on bare hands and arms. A pair of thick gardening gloves solves most of that.
I’d also wear long sleeves for a hard cutback, since you’ll be reaching into the middle of the clump. Some people get mild skin irritation from the plant’s oils, so wash your hands after handling it.
Routine Summer Trimming: Brown Leaves and Untidy Tips
Light pruning in summer means removing what’s dead and shaping what’s untidy, while leaving most green growth in place. The green leaves feed the plant and fuel new stalks.
Remove Dead Leaves Without Pulling Healthy Stalks
Brown leaves should come off. They won’t turn green again, and they hold moisture against the base of the clump.
Here’s how I’d handle them:
- Grip a brown leaf near its base.
- Give it a gentle tug. A fully dead leaf peels away easily.
- If it resists, snip it with your shears close to the base.
- Clear dead material from the center of the clump too.
Never yank hard on a stalk. A firm pull can tear a healthy stalk loose, roots and all, and leave a gap in the clump.
Shorten Green Leaf Tips Without Stripping the Clump
Dry or brown tips on green leaves are fine to trim. Cut at an angle just into the green, following the leaf’s natural pointed shape so it looks tidy.
To control height in summer, you can cut long leaves back by about a third. I’d stop there. Taking off more than a third of the green growth at once slows the plant down in its best growing months.
Brown tips can also point to a care issue, such as dry soil or too little food. Feeding every 2 to 3 weeks in summer with a nitrogen-rich or balanced fertilizer keeps new leaves greener.
Cutting Back Hard in Late Winter or Early Spring
The yearly hard cut clears out winter damage and resets the clump for a strong season. Here is how to cut back lemongrass in three steps, starting with the dead growth and ending at the right height.
Clear Away Dead Foliage First
Start by removing everything that’s clearly dead. Pull or snip brown leaves and stalks from the outside and the middle of the clump.
This step shows you what’s still alive. Healthy stalks feel firm at the base, and if you scrape the outer layer, you’ll see white or pale green inside. Soft, mushy stalks are rotted and should come out completely.
Where Should You Make the Cut?
Cut the whole clump straight across, about 6 to 12 inches above the soil. Gather the leaves in one gloved hand like a ponytail and cut below your hand with shears or a hedge trimmer.
Aim the cut above the white base of the stalks. That lower section holds the growing points, and new leaves will push up from there in a few weeks.
How Much Green Growth Should Remain?
Leave 6 to 12 inches of stalk standing. For a small or young clump, I’d stay closer to 12 inches so it has more reserves.
The plant will look like a stubby brush for a while. That’s normal.
Once soil warms and nights stay above 60°F, healthy plants usually show new green within two to three weeks.
Give it full sun and steady water to speed things along; my post on how much sun lemongrass needs explains why 6 or more hours of direct light makes such a difference.
Trimming Pots Before Bringing Them Indoors
Potted lemongrass in cold regions needs a trim before it comes inside for the winter. A smaller plant fits indoors and needs less light to stay alive.
Reduce the Leaves Before Cold Nights Arrive
Trim the plant before nights drop below 50°F. In much of the Northeast and Midwest, that means late September or early October.
Cut the stalks down to about 6 inches above the soil. Remove any brown leaves and check the pot for insects before you carry it inside.
If you’re still deciding on containers, my guide to how to grow lemongrass in pots covers pot size and soil mix.
Adjust the Trim for Active Growth or Winter Rest
You have two choices for winter, and each calls for a slightly different trim.
- Keep it growing. Trim to 6 to 12 inches and set it in your sunniest window or under a grow light. Water when the top inch of soil is dry. It will look scruffy by spring, which is fine.
- Let it rest. Cut to about 6 inches, move it to a cool, dark spot like a basement or garage that stays above freezing, and water about once a month.
For the growing option, my tips to grow lemongrass indoors help it stay greener until spring. Either way, move it back outside once nights stay above 60°F.
Taming Overgrown or Floppy Clumps
An overgrown clump does best with thinning at the edges and a check of its growing conditions. Cutting the whole thing down in midsummer is rarely the fix.
Thin Older Outer Stalks Instead of Cutting Everything
Thinning opens up the clump and keeps plenty of green growth working for the plant. Start at the outside, where the oldest and thickest stalks grow.
- Pick the tallest, oldest stalks on the outer ring.
- Cut each one at the base, right at soil level.
- Remove about a quarter of the stalks per session.
- Leave the younger stalks in the center alone.
Those outer stalks are also the best ones for cooking. You can harvest lemongrass and thin the clump in the same pass.
Check Growing Conditions If New Leaves Keep Flopping
Floppy leaves that keep falling over after a trim point to a growing problem. Shade is the most common cause, since lemongrass stretches toward light and gets weak.
Other causes to check: