A large sun loving bamboo can be controlled in the following ways:
Natural barriers are the best. A sun loving bamboo will not venture far into the shade of a forest, and no bamboo will cross standing water.
• Mowing Method
A 30 ft expanse of lawn surrounding the area you devote to the running bamboo that can be mowed in the spring will control it.
Bamboo can only send rhizomes out from the edge of the grove as far the distance of the height of the tallest culm in the grove. So if a grove's tallest culm is 20 ft in height, it will not be able to cross an expanse of lawn 30 ft from all sides of the grove.
It will send up new shoots within that 30 ft zone, but keeping these new shoots mowed off each spring will prevent the rhizomes from producing culms and leaves by which to gather energy from the sun to grow any further.
The total area represented in the below illustration is a piece of ground 80 ft in diameter; 30 ft on all sides of a 20 ft diameter grove.
•Trenching Method
Another way to contain a running bamboo is the trenching method. An open trench 12" to 18" wide and deep surrounding the grove on all sides will provide an open view to any rhizomes that attempt to spread beyond the area allowed for the grove. This open trench will be more easily maintained in a clay based soil than in a looser soil such as loam.
Rhizomes only spread once a year during the late summer to early autumn. During a period of a few weeks each year the rhizome will grow from the planting bed into this trench where they can be cut back with pruning shears.
We have successfully contained a small grove of Phyllostachys bissetii to a 6 ft x 8 ft area for 10 years using this method.
If the open trench would pose any aesthetic problems it can be hidden from sight by planting a shrub hedge between it an the garden path.
It should be noted that while the mowing and trenching methods of containment work well for nearly all larger running bamboo species, neither of those methods will work for the small species within the genus Pleioblastus. Rhizomes of those species will simply grow down the sides of a trench instead growing straight out of them as would those of larger species. The reason that the mowing method will not work is due to their ability to form leaves on culm shorter than the mowing height.
Pleioblastus species should either be grown as container plants or planted in very large areas where they can form a mass planting of ground cover.
There are also thick plastic barriers, for putting in the ground, on the market. We do not carry those, but can help you find them.
Clumping bamboo is completely non-invasive. Species within the Fargesia genus only reach a spread of about 12 ft. during it's entire life of 60-100 years. This slow growth lends these species well to small gardens where a larger area of bamboo is not desired. However, any Fargesia species requires shade year round. There is no clumping species hardy this far north, zone 5, that can take sun. The sun loving bamboo hardy here will all run slow to moderately.
Siting -
There is a cold hardy bamboo for nearly any situation, sun or shade, grove use, shrub form, or ground cover. They exist in color patterns varying from dark to light green, even with variegation on the culms and/or leaves. The culms can be for instance green with yellow stripes or vise-versa.
Siting the bamboo is very important. If you live in colder regions such as zones 5-6 it would be best to site the grove in an area with well drained soil where it will not be exposed to winter winds. While cold temperatures are not a problem for hardy species, wind is. Winter wind will quickly desiccate the leaves and culms.
If this happens, new shoots will emerge from the ground in the spring, but the grove will remain stunted never reach its maximum height if this top-killing happens on a yearly basis.
Here in northern Indiana the worse winter winds comes from the west. So planting bamboo on the east side of a windbreak will prevent wind damage.
Fertilizing -
Bamboo will grow okay without fertilizer, but being that it is a heavy feeder it will grow much better if fed properly. First year plantings should only be fertilized with well composted manure as not to burn the new plant. Starting the second year and every year thereafter it should be fertilized three times this year. For good growth you can follow this fertilizing schedule every year after the first year.
Spring ( late Feb.- early March ) high nitrogen, 42-0-0: cover the ground with 3"-4" of composted manure and scatter one cupped hand full of urea per 3 square ft. of manure.
Summer ( mid June ) balanced fertilizer: 20-20-20
Fall ( mid September) low nitrogen: 5-10-10, etc.
Grove Maintenance -
Third or fourth year and every year there after:
In northern climates it takes a little maintenance to make the larger bamboo species look like a nice grove. For the biggest culms, in mid summer after the new shoots have reached full size, remove 1/3 of the smallest and weakest culms. These small ones are usually in the shaded interior of the grove. There they receive no sun light to contribute any energy to the grove. The grove is spending energy to feed these small culms and not getting anything back in return. This culling should not take place until the third or fourth year because doing it before this can weaken the plant or kill it.
For smaller species such as members of the Pleioblastus genus, mowing to a couple inches in height once every few years will rejuvenate the miniature grove.
