Bamboo for Ponds

by Adrian Lawler, Ph.D.
(retired) Aquarium Supervisor (l984-l998) J. L. Scott Aquarium Biloxi, Ms 39530
Original to Aquarticles

Introduction
Bamboo can add visual pleasure to a pond setting, plus provide shade to cool pond waters. It can be used as a screen to separate or hide a pond, and as a barrier to discourage some larger fishing birds from getting to the fish. When you prune back bamboo, the canes can be used as stakes and in many craft projects. The advantages of bamboo far outweigh the disadvantages.

Bamboo has the disadvantages of dropping leaves into ponds plus getting out of control if not managed correctly.

Description
There are over 1200 varieties of bamboo throughout the world; bamboos are the largest members of the grass family, having evergreen leaves that turn yellow and are dropped and replaced in the spring.

There are two basic types of bamboo: clumping (sympodial) and running (monopodial). Generally, tropical types are clumpers and temperate types are runners. I added both types to my farm many years ago for screens and winter food for my livestock, and prefer the clumping type. Running bamboo tends to "run away" from its initial planting place as a screen (unless contained by a rhizome barrier), and as the canes die out your original screening can lessen or disappear or move.

Clumping bamboo has a large root ball and culms arising from the root ball; running bamboo has rhizomes with roots, and culms arising from various points along the rhizomes. Culms can also be called shoots, canes, stems, or stalks, and refer to the above-ground or aerial stems of grasses (including bamboos) and sedges.

When new shoots emerge in spring the maximum base diameter of the culm is set. The shoots telescope to their final height in about 45-60 days and do not grow taller or thicker in diameter. The inner walls thicken and harden and the canes become stronger as they mature. The new culms should surpass the previous culms in height and diameter, as the growing root/rhizome mass and stored energy increases each year. Most culms will live 3-5 years in cold climates. Rhizomes from running bamboos spread in summer and fall. Bamboos are dormant through winter.

Unless cut apart or initially individually planted, all bamboo canes in a canebrake are from one plant via a root ball (clump bamboo), or rhizomes (running bamboo).

Care and Maintenance
Ascertain the requirements of the specific type of bamboo you choose and supply them to get best growing results.

All bamboos require good drainage with filtered sunlight (for dwarf types) to 4-5 hours of sunlight daily (for tall bamboos). Some do best in full sunlight.

Bamboos like moisture, but not excessive, or constant, water. Mulching will retain moisture, lessen competition (with other plants) and create heat (through aerobic decomposition). Use dropped bamboo leaves as mulch to recycle nutrients back to the bamboo.

In general, most bamboos prefer a moderately acidic loamy, organic soil. Bamboos can be planted at any time of the year in areas with mild climates.

Remove bamboo leaves from pond because if allowed to sink and they then undergo anaerobic decay (especially during warm weather), they can foul a pond, producing hydrogen sulfide and methane gases.

Beware of letting bamboo droop over a pond. In addition to having more leaves drop into the pond, birds will nest or roost in the bamboo and fertilize your pond. There is also the possibility that the young birds will fall into the pond and drown. Cut drooping canes at base (so there is little left above ground as a safety hazard).

If you use a rhizome barrier, in the fall cut the rhizomes trying to grow over the barrier. Cut off new shoots from rhizomes whenever they come up in areas not wanted.

Planting/Transplanting
   General information
Get a type that is already growing well in your area. A recently dug up and replanted plant may have a larger cane attached to the root ball or rhizome dug up but usually doesn't have enough root ball or rhizome and thus enough stored energy to produce large, new shoots for several years. Get as large a root ball or section of rhizome as you can handle to get faster production of larger culms. One can get a better start on producing larger culms quicker by using bamboo grown in pots for 1-2 years.

One can tell the maturity of a culm by its color and hardness: (1) new stalks are pretty green and shiny (from waxy coating) and are not completely hardened yet, (2) mature stalks are green-yellow to yellow-green and hardened, and (3) dying or dead stalks are yellow, and have few or no leaves.

Newly planted bamboos need frequent and liberal watering, especially during hot or windy weather. The lack of sufficient water is the leading cause of failure or poor growth of new bamboo plants. However, newly planted bamboos can also suffer from too much water, which can cause excessive leaf drop. Well established bamboos are fairly tolerant of flooding.

Plant either type 2-6 feet from edge of pond to allow room for growth of the bamboo screen and far enough away to lessen liner puncture. Encircle either type of bamboo with a rhizome barrier or plant it inside a pot or tub put into the ground to keep it contained to a limited space. Plant it lower than surrounding ground level to retain water better for needed moisture.

There are several ways to plant/transplant bamboo:
...Cut off and dig up a section of root ball (with canes) from a clumping type.
...Cut a mature stalk (from a clump) into 3-node sections and drive them into ground to the top node.
...Dig up a large enough section of rhizome (with cane) of the running type.
...Plant bamboo (either type) that has grown in a pot for 1-2 years.

   Clumping bamboo
The root ball of a clump must be allowed to reach a certain size to develop culms of a mature height. The space required will vary depending on size of species. Height of culms may be limited if too small a space is allowed for the roots. So, one must decide how much space to allow near the pond to provide enough space for expansion of root ball to get the cane height wanted plus far enough away from the liner so root expansion does not damage liner. It might be advisable to put a section of barrier on the side toward the pond to try to limit growth in that direction.

It is probably best to use clumping bamboo around ponds as running bamboo rhizomes could penetrate pond liner. Since clumping bamboo grows outward in a circle from the initial set, one can space the plantings in order to get the shading/screen pattern wanted. One could also contain clumping bamboo in a buried pot or tub if you are not concerned with height attained. If one is driving in cuttings, put two cuttings at each point where you want clumps to be centered since not all cuttings will sprout.

If you do not need a tall screen of bamboo as soon as possible, or you want to reduce the labor involved, you can start your clumping bamboo as I did years ago. How to start clumping bamboo from cuttings:
…Pick out mature, green-yellow, hardened stalks to cut.
…Cut stalks into lengths of 3 nodes long for each cutting.
…Put cuttings into a bucket of water with bottom bamboo cut downward so cutting will not dry out.
…Transport in bucket to new planting site.
…Use a 2 x 4 or 2 x 6 on top of stalk and 4-6 lb. maul to drive stalks into ground until 2 nodes are below ground and 1 node above.
…Water fairly frequently.

Sprouts will come out of the top node. Next year one will get new stalks, which get taller with each passing year. Using this method, and depending on soil moisture, one third to all of the cuttings driven will survive.

   Running bamboo
Pick stalks that sprouted last year. Dig deep enough to get below the rhizome and get enough of a rhizome piece (12" or more) so stalk has a greater chance of surviving the transplant. Maintain dirt around rhizome throughout moving. Water well for at least a month.

Although I have not tried to start running bamboo by driving sections of mature canes into the ground, with proper moisture it should work.

Control
   Clumping
Clump bamboo stays in a clump, and if the clump gets too big just cut some of the outside stalks. The root ball may spread to threaten the pond liner, so part of the root ball may have to be chopped off.

   Running
If you decide to use running bamboo, plant it inside an enclosed barrier (plastic, metal, or treated plywood) 22-36 inches deep (since the rhizomes grow sideways at a depth of usually about 2-18 inches). The larger and more aggressive running bamboos will need the deeper barriers (to 36"). Slant the barrier away from the bamboo, so that when the rhizomes hit the buried barrier they will be directed upward where you can cut them off.

Most recommend a barrier material of 40 mil thick HDPE (high density polyethylene). One could also plant the running bamboo inside a large pot or bathtub that has been set into the ground.

Another barrier to running bamboo is water. One can also surround bamboo with water to contain it, as rhizomes do not like to be wet all the time.

Running bamboo can be a nuisance to control; it can run (via rhizomes) underground for a good distance before sending up a stalk. I have seen running bamboo (a variety 30-40 feet tall) get away from one busy couple. Growing stalks were pushing up the edges of the tin roof and coming up between the floor boards in the bathroom and other parts of the house; one had to use a chain saw to cut the stalks, and a backhoe to dig up the huge root clumps.

Annual maintenance is a key to controlling bamboo. Cut any unwanted rhizomes or stalks.

One can kill any bamboo by cutting the stalks down until it exhausts its stored energy resources and dies. By continually cutting down the stalks you are not allowing the bamboo to store any more energy from photosynthesis and the plant dies when its resources are depleted.