Roof garden with a new twist

Sedum roof on Fodder at the Great Yorkshire Showground
Sedum roof on Fodder at the Great Yorkshire Showground

During my 38 years as a horticulturist I been asked to do all sorts of things connected with gardens and gardening and last week I added a new experience to my list. It was to inspect and maintain a sedum roof!

This type of roof is getting more and more popular on modern buildings to make them more eco friendly. The benefits are many and include creating a micro-climate for birds, bees and other insects. The plants growing in the roof will absorb water and vastly reduce the amount of water entering drains or soak-a-ways.

Any water running off is filtered by the plant roots and sub-base allowing the water to be recycled and used to flush toilets within the building. A sedum roof is also a good insulator, helping to keep the building cool in summer and warm in winter.

The roof will last for many years and requires only minimal maintenance and in theory will get better each year. The roof I was asked to look at is on Fodder, the farm shop and cafe run by the Yorkshire Agricultural Society on the Great Yorkshire Showground.

Visitors come from all over the region to buy local fresh produce, but I’m sure that most are unaware that above their heads is a 500 square metre roof planted with hundreds of thousands of sedum plants that create a living roof.

Sedum is a hardy, succulent-like plant that forms a low growing, spreading mat. There are many different varieties and several types are used to in the sedum roof to give colour and interest, but also to increase the biodiversity.

The plants are grown on a shallow layer of growing media that has the ability to drain quickly, but also retain some moisture. Sedums are also very drought tolerant, making them ideal for growing in this situation. During the summer, pink, white or yellow flowers are produced that attract bees and pollinating insects into the area. Of course a sedum roof doesn’t have to be large and they can easily be incorporated into a garden setting.

There are several companies that sell sedum matting that can be laid onto the roof of an existing shed or outbuilding with a little preparation beforehand. You can then create your very own sedum roof garden to enjoy for many years.

Jobs for the week

There is still plenty of time to sow fast growing vegetables such as pak choi, Chinese cabbage and chard. Sow directly into the garden and keep the soil moist to help germination.

Net over strawberries as the fruits start to develop and ripen to keep the birds off them.

Support taller growing perennials to prevent them from falling over as they start to flower.