Your Life: How to grow a roof! Gardening.
Thought much about your shed roof recently? Feltclad, algae-covered, a single shoe perched rotting in the gutter. Not all that thrilling.
So why not transform yours into a trendy "living" roof? It makes use of a boring surface and adds an interesting element to your garden - especially if you're short on space. Your neighbours will be green with envy.
3 reasons to do it
Other than simply looking fantastic, living roofs will:
1. Attract wildlife - beneficial insects and useful pollinators will love the new green space.
2. Use up rainwater during the wet season, reducing localised flooding.
3. Have great insulating properties and help keep temperatures inside the shed more constant - cooler in the summer and warmer in winter.
Before you begin
1. Check the roof is strong enough to bear the weight of a green roof and that the shed itself is up to it.
If in doubt, you'll need to install a sturdier framework (see below).
2. Make sure the roof is adequately waterproof. If not, you'll need to upgrade this or install an extra layer (see below).
3. Consult your local council's planning department just in case it needs to give permission.
How to do it
A green roof consists of several layers: Frame: If your roof is weak install a frame for extra support, using posts or timbers to bear its weight. If you still have concerns, make a frame base by laying a sheet of marine plywood or treated timber on top of the existing roof.
The frame will need edges to keep the various layers and plants in place. If the roof is sloping, divide it into about six or eight squares, with a mini bed within each, as in our main picture. This will help to stop everything slipping down.
Root membrane layer:
To stop plant roots and water penetrating the roof, cover it with either a 300micron-thick dampproof membrane, from DIY shops, or a butyl pond liner from a garden centre. I've even heard of people using several layers of opened-out empty compost bags. As well as covering the roof surface, make sure that the layer lines the upright edges.
Next, lay down weed membrane (the sort that goes under gravel paths). This stops soil from penetrating through to the lower layer, while allowing water through.
Over the weed membrane, place a fleecy layer to help retain moisture for the plants. Either buy "geotextile membrane" or, if cash is tight, try old blankets or towels.
Follow with a 4cm layer of crushed brick, limestone chippings, gravel or expanded clay granules. This helps to ensure adequate drainage and prevents the plants' roots from becoming waterlogged.
Once it's in place, you can add a mixture of garden soil and horticultural sand - make sure it's at least 3cm deep. The soil shouldn't be too fertile, so if you have some subsoil available this works well.
Make sure your soil/sand mixture is even textured and any large lumps removed, then try to lay it evenly on to the drainage layer.
Great choices include sedums, like Sedum acre - a hardy succulent that's slow growing, often with attractive, fleshy leaves that contain various shades of red.
They produce small, starry flowers on tall flower spikes. You can buy roll-out sedum mats to lay on to the roof, like a carpet.
Wildflowers and ornamental grasses also work well. Sow from seed or, for a quicker and more reliable effect, buy small plants or "plugs" and put direct into the soil.
For wildflowers suitable for green roofs, check out British wildflower plants at www.wild flowers.co.uk or call 0160 371 6615. A mix of plugs sufficient for a small roof costs just under pounds 40.
Do it now!
Grab a half-moon edger or, if you don't have one, a good, sharp spade to neaten up the lawn and border edges.
Use the edger or spade to cut firmly and vertically down and the end result will make your autumn garden look a great deal smarter.
Do it now and it'll look good until next year. The turf trimmings make a fine addition to the compost heap.
Michaelmas daisies look great in autumn, with their stems studded with daisy flowers in pink, purple or white, each with a lush golden centre.
These shrubby perennials are easy to grow in any sunny or partly shaded spot and will perform well on all but very damp soils.
But take care in extremely dry spots, where they can succumb to powdery mildew infection.
Prune them back when the show is over and give them a bit of a feed in the spring to encourage plenty of new growth.
TRANSFORMED: Living roof, above, and Sedum telephium maximum, right