Fytogreen has a wonderful botanist, Erik van Zuilekom, who designed the plants on our roof. Our main objective was to have a natural indigenous landscape designed to be as self sustaining as possible. The only aesthetic instruction was a meadow like effect with grasses blowing in the wind. We hope to have a bee hive, so this was also considered in the design process. And we would like to encourage as much biodiversity as possible. Fytogreen kindly allowed us to publish the plant design and Erik’s comments so everyone can appreciate what it takes to design a self sustaining ecosystem.
Fytogreen explains the plant design
We are designing for ecological functionality. This planting plan does not represent a set aesthetic, rather a planting starting point from which plants will naturally expand outwards as their genetic imperatives dictate. This process is what lends the garden the ability to adapt, seed freely and function as an ecology.
The shrub areas are a bit more static, as they will expand to maturity and fill their own spaces. Grass species will invariable penetrate into the shrub areas in time as open gaps present themselves for seed to establish in a natural manner. Larger plants dominate, smaller species generally move around and migrate wherever factors are favourable.
The “Planting Mixes” represent open areas of highly diverse, mixed species. These are the shifting tides of the garden as a whole. Plants will seed out from these areas into neighbouring zones. This means the grass species will expand between groundcover and shrub zones in time, thereby linking “meadow” areas further.
All the above are very dynamic, the aesthetic of this garden will change and morph into formations that best suit the species, dictated by the species.
Exotic shrubs (Rosemary and Lavender) are spread through the gardens as functional separation layers, yet have been focussed around the vegetable/herb planter boxes, to draw bees/pollinators to these areas. They function also to supplement as pollen sources for honey production.
Areas around the planter boxes are planted with Dichondra repens, which will handle a bit of foot traffic. This species may die back during harsh summer drought, though will re-emerge when rains return or if irrigation is applied. It will benefit from any moisture draining from the base of the planters.
Species neighbouring the turf areas are deliberately selected to function as barriers to turf encroachment as much as possible. All turf areas, regardless of terrestrial, roof garden or of the turf species, will require general maintenance to constrain. Regular mowing will reduce seed development and keep maintenance much easier. It is suggested the lawn clippings are captured by the mower and disposed of off-site to reduce seed being spread by the mower. This is a basic consideration for most lawns in gardens, even though the turf selection for this garden is carefully considered to be less aggressive than other species.
All plantings and species groupings are considered in terms of plant heights, growth rates, interspecies compatibilities, variations in textures, long term sustainability as well as managing exposures such as wind, shade and sun. Shrubs are generally near the garden perimeter to produce an increasingly graduated foliage effect towards the outside of the garden, thereby maximising views and accessibility to plants.
Further to this, tall grasses are used where the two main garden areas converge, to separate the areas, yet still link them by providing views of soft textures and foliage movement in the breeze from both separate garden areas when viewed from the outside inwards. I believe this creates a sense of mystery whilst simultaneously unifying the areas by providing aesthetic cues that draw the eye through the two separate roof garden landscapes.