How to Get Rid of Cattails in a Pond, and Keep Them Out

Cattails spread by rhizome, so cutting alone makes them denser. Cutting below the waterline, timing, and why leaving a third of them is sensible.

By Zakaria September 21, 2026 4 min read Save to Pinterest

Cattails with brown cigar-shaped seed heads standing in the shallow margin of a still pond — Photo: Thomas Metaxas, CC BY-SA 4.0, via Wikimedia Commons

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Cutting the tops off cattails makes the stand thicker. The plant lives in the rhizome, and the only cut that reaches it is one made below the waterline.

The short answer

Cattails spread by rhizome, so cutting the tops prunes them and usually thickens the stand. The method that works is cutting stems several inches below the waterline in mid to late summer, which floods the hollow stalk and drowns the rhizome, repeated over two or three seasons. Cut after flowering, when the most energy is above the sediment and before reserves move back down for winter. Keep roughly a quarter to a third of the shoreline planted rather than clearing it all — cattails stabilise banks, take up nutrients that would otherwise feed algae, and shelter birds and amphibians. Check permit rules first; shoreline work is regulated in many places.

Cut below the waterline. Cutting tops thickens the stand
Mid to late summer, after flowering
Repeat for two or three seasons. The rhizome has reserves
Keep a quarter to a third. They hold the bank and starve algae
Check permits. Shoreline and wetland work is regulated

Why cutting normally fails

A cattail stand is frequently one connected rhizome mass under the sediment, not a collection of individual plants. Cut the visible growth and the rhizome responds by pushing up more shoots from stored reserves.

That is why casual strimming thickens a stand — you have pruned it.

The below-water cut is the whole trick

A cattail stalk is hollow. Cut several inches below the surface and water floods down the stem into the rhizome, which drowns it.

Cut above the surface and you have given the plant a haircut. Same tool, same afternoon, completely different outcome.

The method

Mid to late summer, after flowering
Cut every stem at least three to four inches below the waterline — long-handled loppers, a marsh rake, or a sickle, working in waders
Remove the cut material from the pond. Left in, it decays, uses oxygen and feeds algae
Check in two or three weeks and cut any regrowth the same way
Repeat the following summer, and probably the one after
Dig rhizomes out where the water is shallow enough to work — a spade or mattock, taking the mat rather than chopping through it, since fragments resprout

Timing and what it achieves

When	Effect
Spring	Little. The rhizome is full and simply regrows
Early summer	Moderate
Mid to late summer, after flowering	Best. Most energy is above the sediment
Autumn, after die-back	Almost nothing
Winter, through ice	Nothing

Other approaches

Shading. Heavy landscape fabric or liner offcuts pinned over a cut area for a full season starves the rhizome of light. Effective, ugly, and only practical on small patches
Deepening the margin. The permanent answer — see below
Aquatic herbicide. Effective and heavily regulated. Generally requires a licensed applicator, and a large die-off at once drops dissolved oxygen enough to kill fish, so it is done in sections. This is a professional decision, not a hardware store one
Grass carp. Not useful — they mostly ignore cattails
Pulling by hand. Works on a handful of new shoots, hopeless on an established stand

The permanent answer is depth

Cattails root in roughly the top eighteen inches to two feet of water. They cannot establish deeper than that.

A gently shelving margin is ideal cattail habitat
Steep sides dropping quickly past two feet give them almost nowhere to grow
Deepening the margin during construction or a dredging operation is the only fix that does not need repeating

Everything else on this page is maintenance you do again in three years.

Keep some of them

Clearing the whole shoreline usually backfires

Cattails take up nutrients that would otherwise feed algae, hold the bank together against erosion, and filter runoff before it reaches open water.

Strip the lot and the common results are a green pond and a crumbling edge.

A quarter to a third of the shoreline is the usual target — controlling where they grow rather than whether they grow. Keep them:

Where runoff enters the pond, so they filter it
On the windward bank, where wave erosion is worst
In one or two blocks rather than a continuous fringe

And clear them:

At the access point and any dock or fishing spot
Where they block the view you built the pond for
Where they are advancing into open water

Before you start

Check the regulations. Many states, provinces and countries regulate work in wetlands and along shorelines, and a pond connected to a stream or wetland may fall under rules covering vegetation removal, dredging and herbicide use.

Aquatic herbicides are separately regulated and generally need a licensed applicator. Contact your state environmental or natural resources agency first — the penalties for getting this wrong are real, and a phone call is free.

Common questions

How do I get rid of cattails in a pond?

Cut them below the waterline, repeatedly, in mid to late summer. Cattails spread by rhizome rather than by seed alone, so cutting the tops merely prunes them and usually makes the stand denser — but a stem cut several inches below the surface floods the rhizome through the hollow stalk and drowns it, which is the only mechanical method that actually kills the plant. Expect to repeat it over two or three seasons, since a mature rhizome mass holds a great deal of stored energy.

Why do cattails keep coming back after I cut them?

Because the plant lives in the rhizome, not the stalk. A cattail stand is often a single connected mass of rhizome under the sediment, and removing the visible growth prompts it to send up more shoots from stored reserves, which is why casual cutting thickens a stand rather than thinning it. The two things that genuinely set it back are cutting below the waterline so the rhizome floods, and physically digging the rhizome out where the water is shallow enough to work.

When is the best time to cut cattails?

Mid to late summer, once the plants have flowered and put their energy into growth above the sediment, and before they draw reserves back down into the rhizome for winter. Cutting at that point removes the most stored energy from the plant. Cutting in spring achieves comparatively little, because the rhizome is full and simply regrows, and cutting after the tops have died back in autumn achieves almost nothing at all.

Should I get rid of all the cattails?

Probably not. Cattails stabilise a bank against erosion, take up nutrients that would otherwise feed algae, filter runoff before it reaches open water, and provide cover and nesting habitat for birds, frogs and dragonflies. Most pond managers aim to keep them to roughly a quarter or a third of the shoreline rather than eliminate them, controlling where they grow rather than whether they grow. Complete removal often produces an algae problem and a crumbling bank.

Do I need a permit to remove cattails?

Often yes, and this is worth checking before starting. Many states, provinces and countries regulate work in wetlands and along shorelines, and a pond that connects to a stream or wetland may fall under rules that cover vegetation removal, dredging and herbicide use. Aquatic herbicides are separately regulated and generally require a licensed applicator. Contact your state environmental or natural resources agency before any substantial work — the penalties are real.

How do I stop cattails coming back for good?

Change the depth, because cattails can only establish in shallow water. They root in roughly the top eighteen inches to two feet, so a pond with steep sides dropping quickly past that depth gives them almost nowhere to grow, while a gently shelving margin is ideal cattail habitat. Deepening the margin during construction or a dredging operation is the only permanent answer; everything else is maintenance you repeat every few years.

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