Planting, Mulch And Shade

What this is

Planting is part of how a building performs, not only how it looks. A layer of mulch slows evaporation from the soil so beds need watering less often, and planting placed on the elevation that takes the strongest afternoon sun reduces how much heat reaches the wall and the glass behind it.

Telling whether your home needs it

Beds that dry out within days of watering, bare soil that crusts over and sheds water rather than absorbing it, and rooms on one side of the house that become uncomfortable on summer afternoons are the signals. Note which walls take the sun latest in the day, since those are the ones that carry heat into the evening.

What the job involves

Mulch goes onto soil that is already damp, in a layer thick enough to block light but held clear of plant stems. Autumn is the usual time because the soil still holds warmth and moisture. For shade, deciduous planting on the sun-facing side gives cover in summer and lets light through once the leaves drop, which suits a house better than evergreen cover in the same position.

Things to watch

Keep planting a sensible distance from walls, drains and any shallow foundation, and keep mulch away from the base of the wall so it does not bridge the damp proof course. Choose species suited to the local soil and rainfall rather than ones that will need constant watering, which would undo the point of the exercise.