Nitrogen Fixing Shrubs for the UK

Understanding the nitrogen cycle is key to successful organic gardening. In the UK, the shrub layer of an edible forest garden contains a number of useful nitrogen fixing plants. Here are some of the useful nitrogen fixing shrubs for use in UK gardens:

Elaeangus angustifoliaElaeagnus (Various)

One of the few nitrogen fixing shrubs that can cope with some shade, Elaeagnus is a useful addition to many gardens in the UK. There are a number of useful shrubs in this group which can provide an edible yield as well as fixing nitrogen. Amongst these are elaeagnus umbellata (autumn olive), elaeagnus angustifolia (Russian olive), Elaeagnus multiflora (goumi) and garden hybrid Elaeagnus x ebbingei. All have the potential to provide edible berries and seeds and can thrive in a wide range of conditions, though they do not always fruit in the UK. Even where they do not fruit, they are still useful in providing nitrogen to neighbouring plants and can increase the yields of fruit trees planted nearby.

GorseGorse (Ulex europaeus)

Gorse is a prickly shrub that is not often used as a garden plant but has excellent potential for use in certain problematic spots. It can cope with highly acid soil and with maritime exposure, though it does require full sun to thrive. Of course, as a nitrogen fixer it can be of benefit to plants growing nearby and both the flowers and the wood have a number of uses. The bright yellow flowers have a pleasant scent that is something like coconut with a hint of vanilla and are used for toiletries, scented candles and dyes. The wood is good for use as kindling and the ashes are rich in potassium, are a good source of fertiliser and were traditionally used to make soap.

BroomBroom (Cytisus scoparius)

Broom is a less prickly, yellow flowered, nitrogen-fixing shrub that can be useful, especially in wildlife gardens. It can tolerate light shade, dry soils, maritime conditions and atmospheric pollution and is wonderful at attracting wildlife. Broom can be a good choice to improve soil conditions where these are currently poor. Traditionally, broom's wood, foliage and flowers have had a number of uses, including for making brooms, baskets, dye, fibres and paper.

Sea BuckthornSea Buckthorn ( Hippophae rhamnoides - L. )

Sea buckthorn is a shrub that can fix nitrogen and can survive and thrive in a range of conditions but needs full sun to grow. It will do well on the sunny fringe of a woodland garden. These shrubs also produce an edible yield, providing berries that are very acidic when raw but full of vitamin C and good for use in juices when combined with other fruits. Unusually for a fruit, the berries are also said to be a fairly good source of essential fatty acids. The plant is also believed to have a range of potential health benefits, though the berries, it is said, should be avoided by pregnant women.

There are plenty of other nitrogen fixing shrubs. For more ideas on which nitrogen fixing plants to choose, check out the articles on nitrogen fixing trees and nitrogen fixing herbaceous plants for UK gardens.