Like any piece of building equipment, a Nedlaw Biofilter does require ongoing care. Unlike soil-based plant walls with individual pockets or pots, our Living Wall Biofilters are quite self sufficient. As a closed loop, hydroponic system, watering is taken care of. Here are the main areas of maintenance requirements:
Plant Pruning and Replacement
Healthy plants will drop their leaves from time to time; while this is normal, it makes sense to keep the area around the wall tidied up. Beyond that, periodic pruning, removal of dead plant material and plant replacement is required. In our experience, roughly 90% of the plants in our Biofilters survive each year.
Component Checks and Replacement
The life expectancy of lighting, pumps, and fans is typically in the order of three to seven years under normal operating conditions. The growth media, TBS, has long life. We have yet to replace an entire growth media on any Biofilter. So, the current life expectancy for TBS is well over 10 years and we anticipate that we can retain 75% of the existing plants during replacement.
Like any collection of plants, living wall biofilters are susceptible to insect attack. Vigilance is key to keeping insects away. One of the best ways to control pests, is to routinely ‘wash’ plants with a diluted soap solution (40 parts water to one part liquid soap). Adding a small amount of rubbing alcohol and/or lemon juice to the solution will further protect plants.
Typically, it takes 2.5 hours to maintain a 200 square foot living walls biofilter each month. Certain wall require elevation equipment and certifications for working at heights.
A Note about Light
A living wall’s life depends on light. For all of our installations, adequate lighting is an integral part of the design and set-up. Although ideal, natural light is not essential for healthy plant growth. We have installed many Biofilters that thrive on artificial light. In terms of maintenance, we only need to address lighting if there has been a change to the building environment that impacts the amount of light the wall is getting. While some plants can tolerate as little as 75 foot-candles, most living walls need at least 70 PPFD for 12 hours per day to succeed.