Cotoneaster microphyllus thymifolius is hard, ground hugging and rather like wire netting with leaves on. Planted in the rock garden it will follow and emphasise every rock and contour in a splendidly affectionate way.

One of the earliest to flower in April is C. x praecox, a lovely ghost of a plant when covered in pale cream flowers and excellent in association with the hybrid heaths. Cytisus purpureus atropurpureus is a fine prostrate dark purple broom for covering slopes in a rock garden. It is lovely on the sloping bank by a rock garden as is also the creamy-white C. x kewensis which flowers in May.

The Common or Scots Broom, C. scoparius, which makes a golden glory of the sheltered valleys in Teesdale has given rise to many hybrids. Cornish Cream grows up to 8 ft. tall with pale yellow flowers in July and together with Darley Dale in crimson and yellow, Firefly in crimson bronze, and Red Sentinel in deep red, it is worth a place in any garden. Cuttings of semi-ripened shoots taken in July – August, 3 to 4 in. long with a heel of old wood, root readily in sharp sand. Make certain the soft pith is not exposed or an imperfect callous forms.

C. salicifolius fructu-luteo berries furiously in my garden with big luscious fruits which are wax like in their creamy opaqueness – a gift to those who delight in the unusual. Last then to the queen, C. salicifoliusflocossus, narrowly columnar, the branches sweep the ground clothed in slender leaves which are hidden in October by masses of small red berries. If you grow floccosus then you must partner it with a cluster of Silver Queen pampas grass. Self-sown seedlings abound from cotoneaster, all are saved, then if found wanting, discarded.

I have a thorn hedge around my garden and just outside the front gate there are standard forms both weeping and normal. There is also even a tiny pygmy on top of the rock garden. As much at home in the bustling city as a mountain glen the thorn is the starling of the shrub world. Undoubtedly it would be easy to lose space and time amongst the species but none have the character of our two indigenous thorns.

I suggest pot-grown plants for this is a shrub which resents root disturbance. The habit is prostrate so the branches should be given a stone to grow over, then the rose-pink flowers are not soiled with mud splashes. A raised position is ideal so that the fragrance so characteristic of this family can be properly appreciated. Propagation is by layering or cuttings taken during July – August into a frame.