Intensive Green Roof Maintenance
As they often resemble regular gardens, the deeper substrate, intensive types of green roof require more maintenance than the extensive variety. The garden element of the roof will need to be watered regularly (though some designs will have an automated system).
In the case of some large intensive green roofs, it may be necessary to hire people to undertake the gardening work (mowing lawns, replacing plants, pruning, weeding etc.) for you. The substrate layer may also need to be maintained. As with the extensive type of green roof, it will also be necessary to keep the drainage outlets and the gravel/shingle perimeter clear of unwanted plants and debris. If the installation has an irrigation system, this will need to be kept in good working order.
In some cases, slow-release fertilisers may be used to keep plants healthy, though caution should be taken so that runoff from the green roof does not pollute the local water supply.
As noted above, the exact level and frequency of maintenance required will depend on the individual characteristics of each installation. The installation company will advise on your green roof’s maintenance requirements, and may even be able to carry it out for you.