Tropical backyard design

On a clear, still night the ground radiates heat away, the air above it cools, gets denser and flows downhill. In open country it keeps going.

In a fenced backyard it does not. A solid boundary at the low end dams it, and the pool of cold air collecting behind that fence is colder than the open frontage of the same property. That corner is where people put the banana, because it looks like the sheltered spot.

The USDA Plant Hardiness Zone Map gives the plot's baseline and nothing about this — it is drawn at a resolution that cannot see a fence. Two practical answers: leave a gap under the boundary at its lowest point so cold air can drain out, or use a permeable hedge there instead of a solid panel, and keep the tender planting at the high end.

The enclosure that traps the cold is also the reason this look is achievable at all outside the tropics.

A banana leaf is a metre of unsupported sail. In an exposed front garden it shreds into ribbons by the first August gale — the plant lives, but the effect the entire style depends on is gone by midsummer. A fenced backyard is the one place on a suburban plot where large-leaved planting keeps its edges intact.

The shelter also holds humidity, which matters for colocasia and ferns that brown at the margins in dry wind. That changes where money goes. In an exposed yard the first purchase is a windbreak; in an enclosed one it has already been paid for, which is most of the reason this pairing is worth doing.

Sort the planting by where it can survive rather than by how tall it grows.

A sunny house wall is the warmest ground on the property. Masonry releases heat overnight, the eaves keep winter rain off the crowns, and the effective difference is often most of a zone. That is where anything marginal goes — a windmill palm in a cold region, ginger lily, a potted plumeria that comes indoors.

The boundary end takes whatever shrugs off a freeze: hardy banana cut down and mulched 300 millimetres deep over the crown, fatsia, hardy hibiscus, canna and colocasia either lifted or mulched depending on how cold it gets. Check each one on the USDA map before buying, because a nursery two states south is growing to a different winter.

The useful sequence is to fix the shapes first and translate them afterwards.

Photograph the yard from the back door with the fence corner in frame and run it through AI Landscape Design, built by Skyble Lab. Read the result as a diagram of leaf sizes and canopy heights rather than as a plant list — that is the part which transfers to a cold climate. Because it edits your photograph, the fence, the shed roof and the neighbour's tree stay where they are, which matters here, since those are the objects casting shade and damming the air.

It has no idea what your winter low is, prices nothing, and draws everything at full size. Take the hardy equivalents from the style hub, then download AI Landscape Design.