Controlling mature Bamboo – Part 2
At this point the very bulky mature bamboo plants had been successfully extracted with rootball intact from their original planting positions and set aside to allow the completed construction of steel mesh re-inforced foundations and concrete block walls 1 meter below ground level. This work effectively created a planting trough below ground level which was lined with a robust bamboo root barrier and part filled with some soil.
Before construction of the raised planter could continue it was necessary to re-position the bamboo plants in the planting trough as the limited space and restrictions made it impossible to use any mechanical methods. The plant handling logistics being a constant and very demanding challenge and our reliance on human effort to move mature plants which were very large and very heavy an incredibly difficult and physical challenge. Also the challenge was also complicated by the sheer physicality of the size and weight of each plant’s rootball (almost 1 m³), made the task of controlling and manoeuvring each plant into position a very strenuous effort. As a pre-caution and reduce the risk of injury it was decided that a better approach to lifting plants into position was to slide them into position, once the retaining wall was set and could withstand the bulk and weight of the plants being manoeuvred into position. Once plants were positioned the planting trough and temporarily secured, enabling the construction of the retaining wall to resume. Later once the wall had set and lined with more root barrier, fresh soil was added to permanently secure all bamboo plants in their new positions.
Construction proceeded with the construction of the limestone wall in drystone finish which was later capped with limestone. In addition to the construction of the raised planting bed for the bamboo screening, a new raised bed was also built for the purposes of growing vegetables and it too was also finished in natural limestone. For added convenience a programmable water irrigation system was installed to manage the watering requirements of bamboo and/or growing vegetables.
All construction works completed, some remedial works to make good ground levels, installation of horticultural weed barrier and a top dressing of bark mulch completed this assignment.
Although the results appear to be a large and appealing raised planting bed, the primary objective of this project was to control the wayward growth of mature bamboo which was encroaching on a play area making it potentially unsafe for children to use because of the risk of injury. The installation of the robust planting bed not only removes permanently any future risk or threat of bamboo root, but the solution also enhances the area by adding more convenient growing space for the growing of vegetables. The design also the many advantages of being a defined structure and with it the many benefits of an extended informal seating area which can also be enjoyed by children and adults. In doing so, the implemented design has addressed very effectively and succeeded in removing any future threat, but also in a new layout which improves the area with wider functionality and purpose, which not only looks great, but requiring less maintenance. A win-win on several fronts and one which now greatly expands the scope and appeal of the original garden.