Using bamboo in landscaping
Author: Janne Nilsson Date Posted:11 February 2016
Bamboo makes a wonderful addition to any tropical and subtropical garden design, but to make bamboo work long term requires carefull selection of species, garden planning and a good understanding of how bamboo grows.
The first consideration is selection of species. This is actually the easy part. Picking a bamboo that will grow to the necessary height, suitable for the use or purpose, and tolerant to your climate. Using our clumping bamboo search feature to short list the suitable species will make this task easy.
What is not so easy is then making the chosen bamboo actually work in your garden. Typical key objectives of any bamboo planting are:
- Thriving bambo with lush green bushy foliage
- No adverse affects on surrounding vegetation
- Minimal leaf litter
- Consideration for your neighbour
- Allow space for bamboo maintenance (thinning out culms)
It is important to understand the growth characteristics of bamboo so that it can be used successfully in a landscape. Bamboo has a very shallow (only 30 or 40cm deep) but wide spread root system. This means that smaller growing plants in the near proximity of the bamboo will ultimately be competing with the bamboo for moisture and nutrients. Due to the size of the bamboo, it usually wins. This means that it can be a little difficult in incorporating bamboo in garden beds with many smaller growing ornamentals surrounding it. There are a few solutions to this:
- Dont plant smaller ornamentals within the critical root zone of the bamboo. This is typically 1m away from clump for small bamboo species (less the 3 or 4m tall), 2m away from medium sizes bamboos (5m to 10m tall), and 3m away from larger bamboos.
- Plant only very hardy plants with large root systems near the bamboo - strelitzias, aspidistras, etc
- Use plants that dont require moisture or nutrients from the soil. Obvious choice being Bromeliads.
- Seperate your smaller growing ornamentals from the bamboo by using root barrier, with the aim being to stop the bamboo roots from growing into the space of the smaller plants. The root barrier needs to go down approximately 50cm into the ground so that the roots dont grow under the barrier.
- Separate garden beds where you want to grow smaller plants from the bamboo by clever planning - perhaps a walkway, paved path, driveway, retaining wall, etc.
Give the bamboo enough space! Bamboo is effectively a clumping giant grass. This means that new shoots will come up from the ground every year, which over a couple months then grow up to full height. The new shoots tend to come up mostly on the outside perimeter of the clump, since that is where there is open ground and better growing conditions. What this means is that with each years new shoots, the clump size gets that little bit bigger, say about 10cm larger in diameter for each year (for smaller bamboo species). This gradual spread needs to be accounted for when planting. In 5 years, expect clump to be atleast 50cm in diameter; In 10 years, expect clumps to be 1m in diameter. Again, these clump sizes are only for small bamboo species (less than 5 or 6m tall). For larger bamboo species, expect about 1m wide clumps in about 5 years, and 2m wide clumps after 10 years.
If space doesnt allow for this gradual increase in clump diameter, then there are things you can do to restrict spread. First is again the use of a root barrier. Root barrier will not just stop roots, but also the new rhizomes and shoots. Place root barrier at the perimeter where you dont want the bamboo to grow past. Keep in mind that the bamboo needs to have roots somewhere - dont surround a bamboo completely with root barrier within close proximity to the clump, as then there is nowhere for the roots to grow, and thus causing the bamboo to grow very poorly. Best is to just have root barrier on one side of the bamboo. If it really needs to be boxed in completely, then be prepared to water and fertilise much more frequently as compensation for the limited root space availble for the bamboo.
Second option to restricting the spread is simply by breaking off new shoots as they come up from the ground. By breaking off all the new shoots on two opposing sides of the clump, and leaving them grow up on the other two sides, you can effectivly elongate the clump make it grow more in a row, rather than round clumps. This is something you have to really keep on top of though during the summer months. At least once per week, new shoots need to be broken off during the main shooting season (December to March).
Think about your neighbours! Your neighbour may not like bamboo shoots poking up on their side of the fence. Make sure you plant far enough away from fences and boudaries so as to not cause any problems. Again, use root barrier along the fence line if need be. Or simply plant further from the fence. 1m away from the fence is highly recommended for bamboo species less that 5 or 6m. If you need to plant closer than this, then use root barrier.
Most plants require some maintenance, and for bamboo that maintenace is in the form of thinning out the clumps. Every winter, it is good practice to remove any old culms from the clumps. Culms live for usually 3 or 4 years, so the aim is to cut them out before they die. This means that there are usually 3 years worth of culms in the clump, with anything older than that being removed. Removing the old culms does a few things; It makes the bamboo look much tidier since all old and scruffly looking culms are removed, leaving only nice new healthy culms. Secondly, it removes any potential leaf litter from dying culms, since you are cutting them out before they drop their leaves and die. And thirdly, it opens up the clump, making it possible for new shoots to once again come up on the inside of the clump. By enabling new shoots to come up inside the clumps, also helps in restricting clump spread, since new shoots are not forced to grow just on the outside perimeter for the clumps.
There is so much more to write about the successful use of bamboo in garden landscaping, so be sure to check future blogs. More is coming on best irrigation practices for bamboo, hedging bamboo, etc.
Hope this has been found usefull information.
Leaf litter.2 March 2017I have Chinese dwarf bamboo that I love. It has formed a very effective hedge or green fence line to our property but I will admit it takes quite a bit of maintenance. This year I have been pruning heavily ( about 3 years old) not unlike what you have mentioned above so that is reassuring. I'm trying to cut the leaf litter down for the coming winter months as that's when it seems to really shed its leaves and if we go away for more than a week we come back to quite a mess. Do you have any other tips for reducing leaf litter? And does it make good compost as I fill my green bin nearly every week with leaf litter??
Bamboo Land Response
Hi there, Chinese Dwarf is a great example of a bamboo that is very much improved if pruned heavily. Cutting the tops off the bamboo and thinning out old culms will definitely help to reduce leaf litter, but most important is to keep the bamboo moist during the dry times of the year with a good deep weekly soaking. Your comments about removing the leaf litter is not helping the situation - Bamboo has a very shallow root system, so a thick layer of mulch around the bamboo clumps is essential in keeping the roots protected. The mulch will keep moisture in the ground. The leaf litter is absolutely the best thing you can have around the base of the clumps....its natures design....the leaf litter will fall around the base of the bamboo, which will then in turn help the bamboo to grow. The best thing you can do is to view the leaf litter as a positive rather than a negative - you are getting all this fantastic mulch for free, spread evenly around the very plants that need it the most. You can rake it up closer the clumps if you want to tidy up a bit, but definitely don't cart it away! Hope this helps. Janne
Thank you18 February 2017Its hard to get information like this We are so happy with our bamboos we planted three years ago_ about 14 clumping variety But now have to deal with what to plant under them as they grow taller abd there is less privacy and lushness again underneath