Centre for Alternative Technology

Roger's Field

Roger Gardening


‘Roger’s Field’ is a 3/4 acre plot of land on a gentle north-west facing slope at CAT’s site. The plot has been tended over the past 30 years by CAT gardener, Roger McLennan. He has been assisted over these years by many volunteer gardeners, usually 2 to 5 people at any one time, who come to CAT for up to 6 months.

The land is primarily used to grow organic vegetables for the CAT restaurant, and for CAT’s staff, students, volunteers and visitors. Crops include salad leaves, beans, broccoli, cabbage, kale, carrots, beetroot, mooli (giant japanese radish), courgette, squash, pumpkin... In fact, one of the few vegetables Roger doesn’t grow on the field is potatoes, as organic potatoes are available cheaply in the area. As well as vegetables, flowers are abundant on the field in summer. These attract pollinators and natural predators of pests, as well as making the field beautiful and fragrant, and providing cut flowers.

Vegetables and flowers are grown up from seed in the polytunnels around site. Roger uses potting mixes of sharp sand, top-soil, and his own site-produced compost and leaf mould. The leaf mould is formed by collecting fallen leaves and leaving them to compost for 2 years, after which they provide a good substitute for peat, which is not used on the plot. Some seeds, particularly those of flowers and herbs, are dried, saved and sown the next year. Interestingly, Roger sows and plants according to the phases of the moon.

A 4-year rotation of brassicas, alliums, root veg, and peas and beans is used. Crops are sown into ground thoroughly cleared of weeds such as couch grass, and hoeing is used to keep weeds (and hopefully slugs!) at bay while the plants establish themselves. After that, ‘friendly’ weeds such as comfrey, borage and chickweed are encouraged. These attract pollinators and natural predators of pests. They also help to avoid bare ground, thus maintaining the soil and preventing nutrients being washed away by the heavy Welsh rain.

Roger tries to employ as little digging as possible in his gardening, in order to maintain a living soil. The roots of plants such as peas, beans, and all salad crops are left in the ground after cropping has finished, along with their nutrients and associated microbes. At the end of the growing season, mulches such as black plastic are used to kill back weeds and clear the ground, without losing nutrients.

Despite these measures, maintaining soil fertility is a challenge. As well as composting all green waste, Roger uses CAT’s high temperature “Rocket” composter to turn the CAT site’s food waste into rich compost in double quick time. For fruit trees and bushes, he can also make use of the output from CAT’s compost toilets (after a good two years of composting!) to “close the loop” and recycle as many nutrients as possible!

All this has enabled ‘Roger’s Field’ to provide nourishing food for over 30 years, and without any artificial pesticides, herbicides, fertiliser or bought-in compost.  

CAT also has an orchard, growing around 30 vintage varieties of apple. The orchard was planted over 30 years ago, on less than ideal growing land heavily shaded by conifers. Nevertheless, it provides an abundance of apples in autumn, as well as a good refuge for wildlife year round.


Article text: Philip James


Philip James worked in the gardens with Roger during the autumn and winter of 2013 after working as a member of CAT's Zero Carbon Britain research team. He is currently developing a Zero Carbon Britain display for our visitor centre.