With rock garden plants thriving in extreme altitudes, it is useful to know those that will live happily in our gardens. Most garden centres have a limited range of rock plants and alpines, so it is worth digging a bit more deeply to source some slightly lesser known, but suitable plants that will complement the investment in stone and labour it took to create the rock garden in the first place.

When deciding on your shortlist of alpines;

• Consider making a plan before visiting the nursery, so the plants are well matched to the conditions you are offering
• Plant all the suggested plants in open, sunny sites with good drainage and reasonably fertile soil
• Most shrubs in time grow too large for smaller rock gardens, but a few are sufficiently slow-growing or compact to be considered
• Allow enough room for plants’ growing habits and plant in groups so as to avoid a ‘bitty’ look
• Be wary of conifers unless they are miniature, as opposed to dwarf (which, ultimately does not mean small, but very slow growing - they will become quite large in time)

The following list includes some of the more attractive and reliable plants for providing interest in different seasons from the many plants which can be grown in smaller rock gardens.

The flowering periods of some plants listed for spring, summer or autumn may overlap but their main period of interest is the one given under each seasonal category.

For a quick guide, take a look at our 10 AGM alpines with impact.

Spring flowering

Evergreens

Arabis alpina subsp. caucasica ‘Little Treasure White’ – Cultivar of native to GB
Cassiope ‘Edinburgh’, C. mertensiana var. gracilis, C. ‘Muirhead’ (cool, moist, acidic soil, humus-rich)
Daphne cneorum, Daphne sericea Collina Group,  Daphne tangutica Retusa Group
Euphorbia myrsinites AGM
Helianthemum nummularium – Native to GB and Ireland
Rhododendron impeditum AGM, R. hanceanum Nanum Group AGM, R. ‘Chikor’ (moist acidic soil, humus-rich)
Gentiana acaulis AGM, G. verna - Native to GB and Ireland
Iberis sempervirens AGM 

Deciduous

Alyssum serpyllifolium
Arabis ferdinandi-coburgi, A. procurrens ‘Variegata’ AGM
Arenaria balearica (cool, moist conditions)
Draba aizoides: Native to GB and Ireland, D. rigida var. bryoides
Oxalis adenophylla AGM, O. enneaphylla AGM
Primula rosea AGM (cool and moist)
Pulsatilla vulgaris AGM: Native to GB
Sinicula epipactis AGM (light shade)
Soldanella alpina (shade, cool, leafy soil)

Summer flowering

Evergreens

Armeria juniperifolia AGM, A. maritima: Native to GB and Ireland
Andromeda polifolia 'Blue Ice': Cultivar of native to GB and Ireland 
A. polifolia ‘Compacta’ AGM (moist acid soil): Cultivar of native to GB and Ireland
Artemisia schmidtiana ‘Nana’ AGM
Dianthus alpinus AGM, D. deltoides AGM: Native to GB,  D. gratianopolitanus AGM: Native to GB and Ireland, D. ‘Little Jock’
Dryas octopetala AGM: Native to GB and Ireland,  D. octopetala ‘Minor’ AGM: Cultivar of native to GB and Ireland
Glandora prostata ‘Grace Ward’ AGM, G.prostrata ‘Heavenly Blue’ AGM (acid soils only)
Helianthemum ‘Amy Baring’ AGM, H. ‘Henfield Brilliant’, H. ‘Mrs C.W. Earle’ AGM,
H. lunulatum, H. oelandicum ssp. alpestre: Native to GB and Ireland
Lewisia cotyledon AGM (shade, in vertical rock crevices)
Phlox douglasii, P. subulata
Primula auricula (not show auriculas),
Ramonda myconi AGM (full shade, north-facing rock crevice)
Sedum anglicum – Native to GB and Ireland
Sagina subulata – Native to GB and Ireland
Sagina subulata ‘Aurea’: Cultivar of native to GB and Ireland
Saxifraga (many, some best in part shade)
Sedum acre ‘Aureum’ – Cultivar of native to GB and Ireland 
Sempervivum (many)
Silene uniflora – Native to GB and Ireland 
Thymus serpyllum – Native to GB and Ireland
Veronica buchananii ‘Minor’, V. ‘Youngii’

Deciduous

Achillea clavennae, A. × lewisii ‘King Edward’ AGM, A. erba-rotta ssp. rupestris
Aethionema ‘Warley Rose’ AGM 
Alchemilla alpina – Native to GB and Ireland
Alyssum spinosum ‘Roseum’ AGM
Anacyclus pyrethrum var. depressus
Androsace carnea, A. lactea, A. lanuginose AGM, A. sarmentosa
Antennaria dioica: Native to GB and Ireland, A. parvifolia
Anthemis marschalliana
Asperula lilaciflora 
Astilbe chinensis var. pumila AGM (moist soil)
Bistorta affinis
Campanula ‘Birch Hybrid’ AGM, C. chamissonis, C. cochlearifolia AGM
Campanula rotundifolia – Native to GB and Ireland 
Cyananthus lobatus, C. microphyllus AGM
Diascia cordata, D. barberae ‘Ruby Field’ AGM
Edraianthus pumilio AGM
Erigeron aurantiacus
Erinus alpinus AGM
Erodium reichardii
Euryops acraeus AGM
Felicia rosulata
Geranium (Cinereum Group) 'Ballerina' AGM, G. dalmaticum AGM, G. sanguineum var. striatum AGM - Variety of native to GB and Ireland
Geranium sanguineum – Native to GB and Ireland 
Globularia cordifolia AGM 
Gypsophila repens ‘Dorothy Teacher’ AGM
Hylotelephium cauticola AGM, H. middendorffianum, H. spurium
Hypericum olympicum 
Leontopodium alpinum 
Linaria alpina : Native to GB and Ireland
Linum suffruticosum subsp. salsoloides ‘Nanum’
Lysimachia nummularia 'Aurea' AGM: Cultivar of native to GB and Ireland
Penstemon pinifolius AGM, P.laetus var. roezlii
Phuopsis stylosa 
Platycodon grandiflorus AGM
Potentilla nitida, P. × tonguei AGM 
Primula frondosa AGM (semi-shade), Primula pedemontana, P. rosea AGM, P. ‘Wanda’ AGM (all moist, cool, leafy/peaty conditions)
Saponaria ocymoides AGM 
Silene acaulis: Native to GB and Ireland, S. schafta AGM
Veronica prostrata AGM, V. ‘Shirley Blue’ AGM, V. wormskjoldii
Viscaria alpina

Autumn flowering

Evergreen

Colchicum autumnale – Native to GB and Ireland 
Colchicum cilicicum, C. kotschyi
Epilobium canum (sheltered, sunny)
Gentiana × macaulayi AGM, G. sino-ornata AGM (moist, fertile, acid)
Crocus kotschyanus AGM, C. speciosus AGM 
Cyclamen hederifolium (moist, leafy soil; sun or semi-shade)
Sternbergia lutea, S. sicula
Zephyranthes candida (full sun, sheltered, milder areas)

Early winter flowering:

Crocus laevigatus

Centenary Crevice Garden at Wisley

Below is a selection of plants you can find in Wisley’s Centenary Crevice Garden;

Aethionema capitatum
Alyssum stribrnyi
Anagallis monellii AGM
Androsace bulleyana
Aquilegia laramiensis
Astragalus utahensis
Benthamiella patagonica
Campanula betulifolia AGM 
Campanula 'Joe Elliott' AGM
Corydalis solida 'Firecracker'
Crepis incana AGM
Cyananthus lobatus giant
Cyclamen cilicium AGM
Daphne × hendersonii 'Kath Dryden'
Dianthus 'Dainty Dame' AGM 
Erigeron aureus 'Canary Bird' AGM
Gentiana 'Shot Silk'
Hepatica nobilis AGM 
Hypericum olympicum AGM
Moltkia petraea
Olsynium douglasii AGM 
Polygala chamaebuxus AGM
Primula 'Rachel Kinnen’
Rhododendron sargentianum
Saponaria 'Bressingham' AGM
Sempervivum giuseppii AGM
Silene alpestris 'Flore Pleno' AGM
Tecophilaea cyanocrocus AGM 
Thymus serpyllum 'Pink Chintz' AGM: Cultivar of native to GB and Ireland
Vitaliana primuliflora
Zaluzianskya 'Orange Eye'

Links

RHS Find a Plant