I recently visited Ryton Gardens, near Coventry, which is the home of the charity “Garden Organic”. Their wonderful planting of late summer perennials and grasses is left standing over winter and only cut down in the spring. This slide show shows just how effective the use of grasses can be at this time of year.
Piet Oudolf and Noel Kingsbury, in their book ‘Designing with Plants’ discuss the different shapes of flowerheads and seedheads that can be left over winter to add interest to the winter garden. They list plants that hold their shape well over winter, including Monarda and Phlomis.
But leaving perennials and grasses to stand over winter is not just an aesthetic decision, it is better for the plant and better for wildlife. In the case of grasses, the plant may well die if you try to move it or cut it down in autumn – the golden rule for grasses is “leave it alone until spring”. For perennials, the dead leaves above ground offer the plant some protection – like a blanket, from the worst of the winter cold and may well help it to survive and grow well the following year. The dead foliage is also where a lot of insects and spiders overwinter. Last year (2011), I remember there being masses of ladybirds hibernating in the dead foliage. This year ladybirds are much thinner on the ground, but even more reason for us to leave places for them to overwinter. If you want to manage the garden organically these insects are essential. Each plays its part in the food chain – wasps eat caterpillars, ladybirds eat greenfly, slugs and snails provide food for birds. Seedheads rosehips, haws and berries that are left over winter provide essential food for birds in this lean time. Leaves that are left on the ground are taken down into the soil by worms where they enrich the soil, and hedgehogs hibernate in piles of leaves beneath hedges. So the message is, if you want wildlife in your garden, don’t be too tidy at this time of year. For more information about how to make your garden wildlife-friendly read Chris Baines’s fabulous book “How to make a Wildlife Garden” published by Frances Lincoln.