5 Tips for Maintaining A Vegetated Roof

It's easier than you think! 

For a vegetated roof to thrive, there are a few maintenance requirements that must be met. It is a common misconception in the industry that some vegetated roofs are maintenance free, but this maintenance doesn't have to be hard! By following these five important maintenance tips, you will see how simple it is to maintain your vegetated roof.

Tip #1: Irrigation

No matter what vegetated roof system you are installing, it will require some form of irrigation. Think of it this way, if the plants in your front yard require water to survive, why wouldn’t the plants on your roof? Water is an essential part of a successful and vibrant vegetated roof, and in some situations an irrigation system can be installed to help automate the watering process. The following are guidelines and do not apply to every vegetated roof, but they can give you a good starting point. Irrigation requirements vary from region to region, roof to roof, and even from one microclimate to another on the same roof.  

  • Extensive System
    • Requires regular watering the first year and minimal watering in the following years
  • Semi-intensive System
    • Requires frequent watering throughout the lifespan of the roof
  • Intensive System
    • Requires the most water, a permanent programmable irrigation system is required

Tip #2: Plant Maintenance
The first year is crucial in the future of your vegetated roof. During this time, plant maintenance is a top priority and should be done each season. Once the roof has made it past the first year, plant maintenance should still be addressed but may require less monitorning. For best results, these steps should continue to be taken yearly. Maintenance requirements will depend on the plant palette, but will follow these general guidelines.

  •  Spring
    • Prune plants and trees; ensure that any dead stems and leaves are removed
    • Apply new fertilizer to promote plant growth
    • Replace any dead plants
    • Adjust irrigation as required
  • Summer
    • Review the irrigation process to ensure plant growth is at full capacity
    • Remove any weeds and fertilize if necessary
    • Replace any dead plants
  • Fall
    • Prune plants and trees; ensure that any dead stems and leaves are removed
    • Apply new fertilizer to promote plant growth, as necessary
    • If located in a northern region, flush and shut down the irrigation system for the winter months

Tip #3: Pest Control

To maintain a health, vibrant green roof with a minimum of pesticides, practice Integrated Pest Management, or IPM. This can easily be done by consulting your state agricultural extension or a local horticulturist for regionally appropriate guidance.

Tip #4: Weed Control

When needed, weeding will be required for every system type. If weeds begin to appear on the vegetated roof, remove weeds by hand. Weed inspections should be done about once a month. As the roof grows and the growing medium has been completely covered with vegetation, the roof should require less frequent weeding. 

Tip #5: Inspections

Inspections are required for all vegetated roof systems to ensure all parts and pieces are performing at full capacity. During these inspections, not only is the vegetation to be looked at, but it is a time to identify and remove any debris in the roof drains and review other components of the roofing system. These inspections can result in increased performance and longevity of the vegetated roofing system.

  •  Extensive Systems
    • Require 4 visits per year for maintenance and inspection
  • Semi-intensive and Intensive
    • Require visits every two weeks

Maintenance is a vital part of a successful vegetated roof and should be taken into consideration when designing the roof. If the upkeep of the roof is not a top priority, the vegetation will not provide its intended benefits and the system will fail. Creating a maintenance plan and staying on track will make maintaining your vegetated roof even easier and will ensure that your vegetated roof will thrive and continue to provide environmental benefits throughout the life of the roof.