During this hot weather period, our trees have been under stress. We ask you not to sit under our trees or enter roped off areas due to the risk of sudden limb drop. Areas including the Lower Woodland Walk, Learning Centre wildlife and picnic areas, and Copper Shelter are closed at this time.

May's Plant of the month

Lithodora diffusa 'Grace Ward' is a fabulous plant for spilling over walls, draping over rocks or forming a ground-hugging mat in a scree garden

Lithodora diffusa 'Grace Ward'We grow this stunning plant on the stone wall in the Foliage Garden and in the Alpine Terrace raised beds where it falls over the edge forming a curtain of intensely blue, star-shaped flowers.

As an evergreen, it has a presence all year, the leaves being small, oblong and coarsely hairy. It is generally pest and disease free and will grow in a sheltered or exposed position, just as long as it is in full sun with very well-drained acidic soil. L. diffusa ‘Grace Ward’ can be a little tricky to establish, and it seems to do better when grown in association with other plants; we grow it with other small shrubs that form a dome or can easily be clipped to shape for a contrast in form.

Winning combinations

On the Alpine Terrace raised bed it grows close to another small-leafed evergreen, Hebe cupressoides 'Boughton Dome'. As its name suggests, it naturally grows in a dome shape and close by, Cedrus brevifolia 'Kenwith' is clipped to shape to enhance the arrangement still further.
Similarly, in the Foliage Garden, Ilex crenata 'Piccolo' and Ozothamnus coralloides provide a contrast in form and we have planted it with mound forming or spreading plants such as saxifrages, Cerastium alpinum var. lanatum and Globularia cordifolia.
Lithodora diffusa 'Grace Ward'Lithodora diffusa 'Grace Ward' AGM will also combine well with heaths and heathers since these plants have similar requirements; it is easily pruned to size, but to freshen the foliage it is best cut back after flowering. This is a plant that will attract butterflies to your garden and if you have trouble with deer, it is said to be resistant to their attentions.
If you are tempted, you will be able to find this plant on sale in the Rosemoor Plant Centre along with other plants to give you inspiration for a sunny wall or raised bed.

Get involved

The Royal Horticultural Society is the UK’s leading gardening charity. We aim to enrich everyone’s life through plants, and make the UK a greener and more beautiful place.