Running Bamboo

The fastest privacy screen money can buy, and the one that most often ends in a lawsuit. Running bamboo spreads underground at 10-20 feet a year, crosses fences and property lines, and costs thousands to remove. This entry is for telling running from clumping, containing it, and getting rid of it.

How to recognize it and why never to plant it: hollow jointed canes with a groove up each internode and two branches per node, and - the real tell - new canes coming up scattered far from the original plant instead of in one tight clump.

You should not plant running bamboo, so what matters is identifying it. All bamboos are giant grasses with hollow, round, jointed canes (culms), papery sheaths on new growth, and leafy branches at the nodes. Phyllostachys, the genus behind nearly every running bamboo sold in America, has two diagnostic features: two branches at each node (one larger, one smaller), and a flattened groove running up one side of each internode, alternating sides as you go up the cane. Canes are typically 10 to 40 feet tall and 1 to 3 inches thick.

The character that actually decides the question is the spread pattern, not the cane. A running bamboo puts up new canes scattered — three feet out into the lawn, ten feet into a border, twenty feet away in the neighbor’s bed — with open ground in between. A clumping bamboo (Fargesia, Bambusa, Chusquea) only ever widens one dense, solid clump by a few inches a year, and there is never a cane standing alone out in the grass. If you are unsure, dig: a running bamboo’s rhizome is long, pale, jointed like a miniature cane, and heads off horizontally; a clumper’s turns upward within a few inches.

One more growth fact shapes everything about control: a bamboo cane reaches its full height and thickness in six to eight weeks and then never grows again. All the plant’s expansion goes into rhizomes and next year’s shoots. That is why cutting canes does nothing on its own, and why interrupting the shoots is the whole game.

Two catalog lookalikes are worth naming, because both get called bamboo. Japanese knotweed is nicknamed Japanese bamboo and does form bamboo-like hollow canes — but it has zig-zag stems, broad shovel-shaped leaves, and dies to the ground every winter. Nandina is sold as heavenly bamboo and is not a bamboo at all; it is a barberry relative with lacy compound leaves and red berries.

How it actually spreads: long leptomorph rhizomes in the top foot of soil, resprouting from any fragment with a live bud. Seed is almost irrelevant - most groves flower once in many decades and then die.

Running bamboo spreads by leptomorph rhizomes: slender, jointed, mostly horizontal underground stems that run through roughly the top 12 inches of soil, occasionally diving deeper to get around an obstacle. Each joint carries a bud that can become either another rhizome or a shoot, and the network stores enormous quantities of starch — which is why a cut grove comes back with such force and why control has to be measured in years rather than weeks.

Every fragment with a live bud is a new plant. That makes soil movement the main long-distance vector: dumped clumps, shared divisions over the fence, contaminated fill, and rototilling through a rhizome mat all start new groves. It is also why digging half-heartedly makes things worse — a spade that chops a rhizome into six pieces has just planted six bamboos.

Seed barely matters. Most bamboo species flower gregariously, meaning every plant of a clone worldwide flowers in the same few years after intervals that can run from 30 to 120 years, sets seed, and then dies. If your grove suddenly flowers, turns straw-colored, and collapses, that is what happened; it is not a disease, and it is the one time a grove can be removed cheaply.

Containment or removal, not care: a maintained 60-mil barrier or annual root-pruned trench holds it; getting rid of it means cutting everything down and knocking off every shoot for two to three seasons, or excavating the whole rhizome mass.

If you are keeping it, contain it properly. The standard is a continuous 60-mil HDPE rhizome barrier buried 24 to 30 inches deep, sloped slightly outward, with about 2 inches standing proud of the soil so escaping rhizomes are deflected up where you can see them. The seams must be clamped, not merely overlapped, and the barrier is only half the job: you have to walk it every year in late summer and cut off whatever has climbed over the lip. The low-tech equivalent works just as well — an open trench or a regularly mown strip about a foot deep around the grove, inspected and re-cut annually. What does not work is a bed edging, a landscape-fabric skirt, a concrete path, or a fence.

If you are removing it, plan on years. The reliable non-chemical method is starvation. Cut or mow every cane flat to the ground, then return every week or two through the whole growing season and knock down every new shoot while it is soft. Repeat for two, usually three seasons. The rhizomes are living on stored starch; deny them leaves long enough and the network dies. Mowing a bamboo patch on a lawn schedule does the same thing and is why bamboo never invades a mown lawn.

Excavation is the fast option and the expensive one: the entire rhizome mass has to come out, which usually means a machine and a foot or more of soil, and any fragment left behind restarts the clock. It is what most professional removals amount to.

If you use herbicide, the pattern that works is to cut the grove down, let it releaf, and treat the fresh foliage — bamboo is a grass, so grass-active products apply, and repeat treatments are normal. Use a product whose label lists the site you are actually treating (lawn, ornamental bed, fencerow, non-crop area), and follow that label exactly: it is a legally binding document, and it also tells you what you may plant afterward. Do not treat near a pond, ditch, or stream unless the product is specifically labeled for aquatic sites. Expect several seasons of follow-up regardless of method — anyone promising a one-application fix has not removed bamboo before.

Bamboo shoots are a genuine vegetable, but only after peeling and a long uncovered boil - raw shoots are cyanogenic. Cutting shoots is also a control method, which makes this the one honest use for a grove you already have.

Bamboo shoots are one of the great vegetables of East and Southeast Asia, and the spring shoots of Phyllostachys are exactly what is eaten — P. edulis (moso) is the main commercial species, and the common ornamental runners are all usable. Cut them short and fat, before the sheaths open and the shoot greens up, taking them flush with the ground with a sharp spade. That is also, conveniently, the single best control action there is.

The preparation rule is not optional. Fresh shoots contain cyanogenic glycosides (taxiphyllin above all), which release hydrogen cyanide when the tissue is cut or chewed. Strip off the tough sheaths, trim the woody base and the pointed tip, slice the shoot, and boil it in plenty of water in an uncovered pot for at least 20 minutes — the pot stays open because the volatile compounds have to leave. Drain, rinse, and taste: mild and sweet is done, still bitter means boil again in fresh water or throw it out. Never eat bamboo shoots raw, and do not treat a quick steam or a stir-fry as sufficient cooking. (Canned shoots have already been processed and are ready as sold.)

After that, they are excellent — crisp, faintly sweet, and good in stir-fries, braises, soups, and pickles. Just do not let a bag of shoots become the argument for planting a grove. Harvesting shoots from bamboo you already have is sensible; planting running bamboo in order to harvest shoots is how people end up with the rest of this page.

Running or clumping, the neighbor question, whether it wrecks foundations, why cutting alone fails, what to do when a grove flowers and dies, and what to plant instead.

Is mine running or clumping? Look at where new canes come up. Scattered canes with open ground between them, or a cane out in the lawn, means running. A single dense clump widening a few inches a year means clumping. Dig if you need to: a running rhizome is long, pale, and horizontal; a clumper’s turns up almost immediately.

Can I just cut it down? Not once. Cutting canes removes this year’s leaves and nothing else — the rhizomes hold years of stored starch and will re-shoot hard. Cutting only works as repeated cutting: every cane down, then every new shoot knocked off through two or three full growing seasons.

Will it break my foundation? There is no good evidence that bamboo cracks sound concrete. What it genuinely does is exploit what is already open: it comes up through expansion joints, paver sand, asphalt edges, cracks, and the gap beside a footing, and shoots can lift pavers and deck boards and appear inside garages and crawlspaces. That is a real and expensive nuisance, and it is a reason to keep it well away from structures — but the horror story about bamboo destroying foundations is overstated.

My neighbor’s bamboo is coming into my yard. In most places you may cut what crosses onto your property, and a maintained trench or barrier on your own side of the line is the practical defense. Whether the neighbor owes you anything depends on where you live — Connecticut and a number of northeastern towns have specific bamboo rules, most places do not — so check your town code first, talk to the neighbor second, and treat a lawyer as the last resort rather than the first.

Is it illegal to plant? In some places, yes or nearly so. Connecticut regulates planting near property lines and holds owners responsible for spread; many New York and New Jersey municipalities require containment, setbacks, or removal, and some require disclosure at sale. There is no federal listing. Check your own town before you buy anything labeled bamboo.

It flowered and then died. That is gregarious flowering — bamboo clones flower once every few decades, set seed, and die. Nothing you did caused it. Take the opportunity: a flowering grove is at its weakest and easiest to remove.

The cut stubs stab through my shoes. Cut culms and shoots leave hard angled spikes. Always cut flush with the ground, and go back and re-cut anything left standing a few inches proud.

What should I plant instead? For an evergreen screen, a clumping bamboo (Fargesia in cool climates, Bambusa in zone 8 and warmer) does the same job without running. For a native alternative, tall warm-season grasses like switchgrass and big bluestem give a 5-8 foot summer screen that supports wildlife, and inkberry holly, ninebark, or elderberry make a real hedge.

Introduced to the US in the 1880s-1900s by USDA plant explorers and promoted for erosion control, poles, and shoots, running bamboo became the suburban privacy screen of the late 20th century - and then the subject of the first municipal bamboo ordinances.

Bamboo arrived in the United States as a serious agricultural project. USDA plant explorers, most famously David Fairchild, imported dozens of Asian species around the turn of the twentieth century, and a federal bamboo research station near Savannah, Georgia spent decades trialing them for poles, paper pulp, erosion control, and shoots. Many of the runners naturalized from those trials and from the nursery trade that followed, and golden bamboo (Phyllostachys aurea) is now thoroughly established along streams, roadsides, and old homesites across the Southeast.

The suburban chapter came later. From the 1970s onward running bamboo was marketed hard as an instant privacy screen — cheap, evergreen, and startlingly fast — and homeowners planted it along thousands of property lines with no idea what a leptomorph rhizome was. The consequences arrived on a predictable ten-year delay, and by the 2000s municipalities in New York, New Jersey, and Connecticut were writing bamboo into their codes, with Connecticut passing a state law in 2013. It is one of the clearest cases in American gardening of a plant whose sale was never restricted until neighbors started suing each other.

Hardy across roughly zones 5-10 depending on species, and most aggressive in the warm, humid Southeast and the maritime Pacific Northwest; hard winters kill canes back but not rhizomes, so cold does not contain it.

The running bamboos cover an enormous climate range. The hardiest — Phyllostachys bissetii, P. aureosulcata — take roughly -10°F to -20°F and are grown into zone 5; most of the rest are comfortable in zones 6-10. Spread is fastest where the growing season is long and wet: the humid Southeast, where golden bamboo has naturalized widely, and the maritime Pacific Northwest, where mild winters and constant moisture let rhizomes run nearly year-round.

Cold does not contain it, which is the point people get wrong. In a hard winter the canes may brown off or die outright, and the grove looks finished — but the rhizomes are insulated underground and survive, and the grove re-shoots from the ground in spring, often more densely than before. In the far North a top-killed bamboo behaves like a coarse perennial grass rather than a screen, which is a good reason not to plant it there either.

Drought and deep shade slow it. Poor, dry, compacted soil and heavy shade will hold a grove to a crawl for years, and that is usually why an old planting looks harmless — until an irrigation line, a wet season, or a neighbor’s new lawn gives it what it was missing. Wherever you are, the guidance is the same: identify whether it runs, contain it with a maintained barrier or trench if you keep it, and remove it while it is still measured in feet rather than yards.