Ask the experts Green roof, shelving, cleaning and more
We’d like to create a garden on our shed roof. Which plants should we choose, and how would we care for them?
CAROLINE TILSTON SAYS
Installing a green roof is a wonderful way to bring extra planting space and provide a wildlife habitat. When you’re deciding what to grow, it helps to think of the roof area as a very large and very shallow container – so you need plants with equally shallow roots and the ability to withstand some dry periods. Alpines such as sedums and thrift are ideal for this as they’ve developed to survive by clinging onto hillsides in little pockets of soil.
Another good option is to try wildflowers that would colonise infertile, rocky soils. Look for wildflower seed mixes intended for green roofs; these will include cowslips, daisies and vetches. Finally you could just let nature take its course – provide a growing medium and just wait and see what comes. The poor conditions should deter big weeds such as nettles, and encourage more delicate weeds and wildflowers that are native to your area.
With all of these, the essential maintenance issue will be to make sure your roof garden doesn’t dry out completely in the summer, especially in the first year or so while it’s getting established. And weeding can be a real issue given its position – trying to pull them off the roof from between the alpines can be a bit of a tricky job, but get a hoe with an extra-long handle and that should make things easier.
Alpine plants such as sedums and thrift grow well on roofs