Flowers: A Monthly Calendar by Colour - May

This section will assist you in choosing flower colour for your garden, month by month, throughout the year. It will allow you to create a colour for a planted feature that will continue its themed display throughout each of the four seasons. Try creating a White garden, a Blue garden or even a Pink garden. Mix White and Yellow plants for a cottage garden look or Orange and Blue for a contemporary and contrasting display.

White/Cream

Trees

AESCULUS HIPPOCASTANUM. ‘HORES CHESTNUT’. Bears huge flower candles.
- ‘BAUMANII’ (FLORE PLENO). Double white; shorter candles.
CRATAEGUS X LAVALLEI (‘CARRIEREI’). Large white flowers, abundant.
DAVIDIA. “HANDKERCHIEF TREE”. Conspicuous white bracts.
FRAXINUS ORNUS. ‘MANNA OR FLOWERING ASH”. Scented creamy white flowers.
MALUS ‘EVERESTE’. Red buds opening to white flowers followed by red flushed, orange-yellow fruits.
‘GOLDEN HORNET’. White flowers in first half of month.
HUPEHENSIS. Fragrant white flowers, pink in bud. Later half of month.
‘JOHN DOWNIE’. Pink in bud opening white in later half of month.
‘RED JADE’. Flowers white or blush pink in first fortnight.
‘RED SENTINEL’. White flowers in first fortnight.
SARGENTII. Small, scented white flowers in later half.
MESPILUS GERMANICA ‘NOTTINGHAM’. “MEDLAR”. White flowers, single.
PRUNUS ‘LONGIPES’. Pink buds; large fimbriated double pure white flowers.
PADUS. Pendant racemes to 15cm long, cup-shaped fragrant flowers 1.5cm across.
- ‘WATERERI’. Pendulous racemes of white flowers; late.
SERRULA (SERRULA ‘TIBETICA’). Small white flowers in masses.
VIRGINIANA ‘SHUBERT’. Dense racemes of white flowers.
SORBUS ARIA AND AUCUPARIA. All bear flattened heads of creamy white flowers during May and into June.

Shrubs

CAMELLIA JAPONICA FORMS E. Flower February/early May.
CHAENOMELES SPECIOSA ‘NIVALIS’. Pure white flowers on erect shoots.
- ‘WINTER SNOW’. Pure white double flowers, bright green early foliage.
CHOISYA IN VARIETY E. Fragrant white star-like flowers in May and spasmodically throughout the year.
CORDYLINE AUSTRALIS E. Small, fragrant creamy white flowers in panicles.
CYTISUS X PRAECOX ‘ALBUS’. The white flowered form of “Warminster Broom”.
DEUTZIA X ROSEA ‘CAMPANULATA’. White “bells” with purple calyces.
ELAEAGNUS COMMUTATA. Small, very fragrant, silvery flowers in profusion.
PARVIFOLIA S. Small, white sweetly scented, fluffy flowers.
EXOCHORDA MACRANTHA. Pure white single flowers on erect racemes.
HEBE PIMELEOIDES ‘QUICKSILVER’ E. White flowers with silver blue leaves.
LEUCOTHOE FONTANESIANA ‘RAINBOW’ E. Small flowers in bunches.
MAGNOLIA SOULANGIANA. “Tulip” flowers, white within, purple tinged without.
- ‘ALBA SUPERBA’. Pure white, very fragrant, waxy flowers.
OLEARIA X SCILLONIENSIS E. Masses of “Daisy”-like white flowers; late May.
OSMANTHUS X BURKWOODII E. Small, tubular fragrant white flowers.
 DELAVAYI E. Masses of small tubular sweetly scented flowers.
PIERIS FORMS. White flowers in terminal, drooping panicles.
PONCIRUS TRIFOLIATA. Sweetly scented, single white flowers 5cm across.
PRUNUS LAUROCERASUS AND FORMS E. White flowers in spikes.
RHODODENDRON E. Hardy Hybrids and Yakushimanum Hybrids, usually flower well into June.
PTARMIGAN. Masses of white flowers. April/May.
‘SNOW LADY’. Lovely white flowers. March/April.
AZALEA. Deciduous varieties. Flower profusely usually until mid-June.
SALIX HASTATA ‘WEHRHAHNII’. Silvery white catkins like icicles.
SAMBUCUS RACEMOSA ‘PLUMOSA AUREA’. White flowers with young leaves.
SKIMMIA X CONFUSA ‘KEW GREEN’ E. White/yellow buds open white.
JAPONICA ‘FRAGRANS’ E. Scented white flowers in April/May.
- ‘VEITCHII’ E. Fragrant, star-shaped, cream-white flowers in April/May.
SPIRAEA X ‘ARGUTA’. ‘THE BRIDAL WREATH’. Dainty white flowers.
X CINEREA ‘GREFSHEIM’. Masses of small white flower clusters.
X VANHOUTTEI. Pure white flower heads and grey green leaves.
SYRINGA (Lilac) ‘MADAME LEMOINE’. Well scented, double white flowers.
‘MAUD NOTCUTT’. Pure white single flowers in fine heads.
‘VESTALE’. Rather loose heads, scented. Fairly compact.
VIBURNUM X BURKWOODII E. Pink buds open to fragrant, white corymbs 10 cm. across.
- ‘ANNE RUSSELL’. Round trusses of pink buds then scented white flowers.
X CARLCEPHALUM. Fragrant white flowers in clusters up to 12cm across.
CARLESII. Sweetly scented pink-budded, white rounded flower heads.
- ‘AURORA’. Rounded heads of pink flowers open from red buds.
X JUDDII. Exquisitely scented; pale pink buds then white flowers.
PLICATUM ‘MARIESII’. “JAPANESE SNOWBALL”. White florets make the effect of a snow laden bush.
- ‘SUMMER SNOWFLAKE’. Tiered branches and white lace-cap like flower heads.
RHYTIDOPHYLLUM E. Buff white flowers in terminal heads.
SARGENTII ‘ONODAGA’. Creamy-white lace-cap flowers. May/June.
VINCA MINOR ‘GERTRUDE JEKYLL’ E. White flowers. Neat habit.

Climbers

CLEMATIS ARMANDII E. Waxy white flower clusters in leaf axils. Glossy leaves.
‘ARTIC QUEEN’ (EVITWO). Double white flowers, yellow anthers.
‘GILLIAN BLADES’. Pure white wavy edged flowers. Also flowers August/Sept.
‘HENYRI’. Creamy white flowers with dark stamens.
‘NELLY MOSER’. Blush white with carmine red bar.
MONTANA ‘GRANDIFLORA’. Large snow white small scented flowers.
WISTERIA  VENUSTA. Broad white trusses.

Perennials

BERGENIA ‘BRESSINGHAM WHITE’ E. 30cm. Pure colour. May/June.
‘SILVER LIGHT’ E. 30cm. White flowers with pink glow.
CONVALLARIA MAJALIS. Pure white, bright green early foliage.
DICENTRA SPECTABILIS ‘ALBA’. 60cm. Ivory white, locket-like flowers.
HELLEBORUS ARGUTIFOLIUS E. 60cm. Multi heads of apple green flowers.
IBERIS ‘SNOWFLAKE’. ‘CANDYTUFT’ E. 25cm. White flowers April/June.
IRIS ‘LILLI WHITE’. 25cm. Pure white with ruffled falls.
POLYGONATUM X HYBRIDUM. ‘SOLOMON’S SEAL’. 80cm. Greenish white bells.

Yellow/Orange

Trees

CARAGANA ARBORESCENS. ‘PEA TRESS’. Yellow flowers typical of “Peas”.
LABURNUM in variety. Predominantly yellow flowers.

Shrubs

BERBERIS - deciduous varieties. All have short panicles of yellow flowers, some tinted, or suffused, in May/June.
BERBERIS - evergreen varieties divide into yellow or orange groups.

Yellow flowerers

buxifolia ‘Nana’     
julianae E
candidula E     
- ‘Amstelveen’ E     
verruculosa E
gagnepainii E      
x stenophylla E

Orange flowerer

darwinii E. Crimson tinted yellow flowers in 3cm long racemes.

COROKIA COTONEASTER E. Diminutive, star-like yellow flowers.
CORONILLA VALENTINA GLAUCA E. Rich yellow, pea-shaped, scented flowers.
CYTISUS SCOPARIUS ‘GOLDEN SUNLIGHT’. Rich yellow flowers. Strong grower.

Species.

X PRAECOX ‘WARMISTER’. Long lasting, creamy yellow flowers in masses.
ENKIANTHUS CAMPANULATUS. Bell shaped flowers, creamy-yellow veined red.
GENISTA HISPANICA. Golden yellow “cushions” in May/June.
LYDIA. Small bright yellow flowers on grey-green shoots.
PILOSA. Twiggy carpets with bright yellow flowers.
KERRIA JAPONICA. Single yellow buttercup-like flowers of 4cm across.
- ‘PLENIFLORA’. Fully double, bright yellow flowers.
- ‘VARIEGATA’. Single yellow, fairly small flowers.
PAEONIA LUTEA LUDOWII. Single, golden yellow flowers up to 10cm across.
POTENTILLA FRUITICOSA ‘JACKMAN’S VARIETY’. Large yellow flowers through summer.
RHODODENDRON. AZALEA. Deciduous varieties. Flower until mid-June.
RHODODENDRON LUTEUM (PONTICA). Scented, clear orange-yellow flowers.
SYRINGA (Lilac) ‘PRIMROSE’. Small pips make primrose-coloured heads.
ULEX EUROPAEUS. ‘GORSE’. Golden yellow flowers. Main display April/May.
- ‘PLENUS’ E. A superb sight when in full flower.

Perennials

AURINIA SAXATILE ‘COMPACTUM’. Golden yellow. Greyish foliage.
CALTHA PALUSTRIS ‘PLENA’. 30cm. Large, fully double “King-cups”.
DORONICUM ‘LITTLE LEO’. 30-35cm. Yellow flowers, semi-double.
EPIMEDIUM X PERRALCHICUM ‘FROHNLEITEN’. 35cm. Long toothed leaflets and bright yellow flowers.
X VERSICOLOR ‘SULPHUREUM’ S. 30cm. high sprays of pale yellow flowers.
EUPHORBIA AMYGDALOIDES VAR ROBBIAE E. 60cm. Yellow-green heads dark foliage.
- VAR. ‘PURPUREA’ (‘RUBRA’) E. 45cm. Bright yellow bracts.
GRIFFITHII ‘FIRE GLOW’. 60cm. Brilliant orange flame coloured heads.
MYRSINITES E. 15cm. Lime yellow flower heads. Glaucous foliage.
WULFENII E. 80cm. Greeny yellow flowers until June. Glaucous foliage.
GEUM ‘LADY STRATHEDEN’. 50cm. Semi-double golden yellow. Wiry stems.
IRIS ‘POGO’. 25-35cm. Chrome yellow with reddish spot on the fall.
TROLLIUS. ‘GLOBE FLOWER’. Large globular buttercup-like flowers.
CHINENSIS ‘GOLDEN QUEEN’. 60cm. Bright orange with prominent stamens.
X CULTORUM ‘CHEDDAR’. 60cm. Double lemon yellow.
WALDSTEINIA TERNATA E. Clear yellow flowers on 8cm spikes. Glossy.

Red/Pink

Trees

AESCULUS X CARNEA ‘BRIOTTII’. Ruby red flower “candles”.
CERCIS SILIQUASTRUM. Masses of red-pink buds opening to pink flowers.
CRATAEGUS OXYCANTHA ‘ROSEA FLORE PLENO’. Double pink flowers.
MALUS ‘PINK PERFECTION’. Double pink, scented flowers. Late.
‘ROYALITY’. Large, mid-pink flowers in first half of season.
PRUNUS PADUS ‘PURPLE QUEEN’. Very attractive pale pink flowers in racemes.
‘KANZAN’. Deep pink buds open to fully double rich pink flowers.
‘PINK PERFECTION’. Carmine buds; double rosy pink flowers.
‘ROYAL BURGUNDY’. Rose-pink double flowers in abundance.
‘SHIROFUGEN’. Purplish pink buds, blush white then pink.

Shrubs

CAMELLIA FORMS E. Flower February/early May according to season.
CHAENOMELES JAPONICA AND SPECIOSA FORMS. Red and pink shades.
CRINODENDRON HOOKERIANUM E. Rich crimson pendent “lanterns”.
CYTISUS ‘BURKWOODII’. Maroon flowers, wings crimson.
DAPHNE X BURKWOODII ‘SOMERSET’ S. Soft mauve-pink flowers.
DEUTZIA X ELEGANTISSIMA ‘ROSEALIND’. Deep carmine pink. May/June.
ERICA CARNEA FORMS E. See April list.
GAULTHERIA SHALLON E. Pinkish white flowers in clusters.
KOLKWITZIA AMABILIS ‘PINK CLOUD’. “FOXGLOVE” flowers pink/yellow.
LEPTOSPERMUM SCOPARIUM FORMS E. Small, bright crimson/red flowers.
MAGNOLIA LILIIFLORA ‘NIGRA’. Dark vinous purple “tulip” flowers.
SOULANGIANA ‘RUSTICA RUBRA’. Colours range from mauve to purple.
PAEONIA DELAVAYI HYBRIDS. Single flowers; crimson shades, yellow anthers.
PIERIS ‘VALLEY ROSE’ E. Pink flowers in spring.
PITTOSPORUM TENUIFOLIUM E. Dark purple honey-scented flowers.
POTENTILLA FRUTICOSA ‘PINK BEAUTY’. Both single- and semi-double soft pink flowers from spring to autumn.
RHODODENDRON E. Hardy Hybrids and Yakushimanum Hybrids usually flower profusely, well into June.
AZALEA E. Low and spreading bushes often hidden by clouds of flowers.

Pink Shades.

RIBES SPECIOSUM S. Rich red, “Fuchsia”-like flowers in pendent clusters.
SYRINGA (Lilac) ‘CONGO’. Dark lilac red; well scented. Very free.
‘CHARLES JOLY’. Dark purplish red flowers, well scented.
X HYACINTHIFLORA ‘ESTHER STALEY’. Carmine buds opening bright pink. Early.
‘MADAME A BUCHNER’. Rose shaded pinkish mauve pips. Well scented.
 ‘MRS EDWARD HARDING’. Semi-double, scented red flowers.
‘SENSATION’. Purple red flowers edged white.
‘SOUVENIR DE L’SPATH’. Deep wine red scented flowers.

Syringa Canadian Hybrids

‘BELLICENT’. Fragrant rose coloured flowers in late May/June.
‘ELINOR’. Dark purplish red buds opening to pale lilac.

Syringa species

MEYERI ‘PALIBIN’. Lavender pink flowers. Dwarf.
MICROPHYLLA ‘SUPERBA’. Fragrant rosy pink flowers, and again in September.
TAMARIX TETRANDA. Light pink racemes in late May/early June.
WEIGELA HYBRIDS. Profuse flowerers in late May/June.

Climbers

CLEMATIS - Large flowered Varieties
‘DR RUPPLE’. Deep rose, pinker darker bar.
‘ELEANOR OF GUILDFORD’. Large pearl-pink flowers with ivory strip along mid-rib, from May to early June.
‘NELLY MOSER’. Blush white with carmine bar.
‘PINK CHAMPAGNE’. Pink flowers with silvery bar. Also July/Sept.
 
Small-flowered Varieties

ALPINA ‘PINK FLAMINGO’. Reddish-pink, white veined, double nodding flowers.
MACROPETALA ‘MARKHAMS PINK’. Lavender pink, semi-double nodding flowers.
MONTANA VARIETIES. Vigorous. Tri-foliate, greyish-green leaves. Scented flowers.

Perennials

AQUILEGIA ‘CRIMSON STAR’. 50cm. Crimson and white flowers.
VULGARIS ‘NORA BARLOW’. 70cm. Double flowers suffused red, pink, green.
AUBRIETA. Pink and Red shades. Flowering freely March-May.
BERGENIA. Large, rounded evergreen leaves, excellent cover.
‘EVENING GLOW’ E. 30cm. Dark purple red flowers. Bronze foliage.
DICENTRA SPECTABILIS ‘BLEEDING HEART’. Locket-like flowers, pink/white.
GERANIUM MACRORRHIZUM ‘INGWERSEN’S VAR’. S. 45cm. Soft pink. Good cover.
SANGUINEUM ‘MAX FREI’. Deep magenta flowers. May to August.
GEUM ‘BORISII’. 30cm. Rich orange scarlet flowers on wiry stems.
‘MRS BRADSHAW’. 50cm. Flaming brick red double flowers.
INCARVILLEA DELAVAYII. 45cm. Bright rose “Gloxinia”-like flowers.
LAMIUM MACULATUM ‘BEACON SILVER’ E. 10cm. Short pink spikes.
PHLOX dDOUGLASII ‘CRACKERJACK’ E. 10cm. Flowers bright crimson or magenta.
PRIMULA PULVERULENTA. 45cm. Bright red candelabras.
PULMONARIA ‘MRS MOON’. 20cm. Rose coloured flowers. Blotched leaves.
SAPONARIA OCYMOIDES. 15cm. Trailing plants with deep pink flowers.
SAXIFRAGA UMBROSA E. 20cm. Dense mats of green rosettes. Pink spires.
SYMPHYTUM GRANDIFLORUM ‘HIDCOTE PINK’. 45cm. Pink/white ground cover.
TANACETUM (PYRETHRUM). Invaluable for early flower and for cutting.
‘EILEEN MAY ROBINSON’. 60cm. Single salmon pink.

Blue/Mauve

Trees

PAULOWNIATOMENTOSA (IMPERIALIS). Mauve “Foxglove” flowers.

Shrubs

CEANOTHUS ‘BLUE MOUND’ E. Bright blue flowers in rounded clusters on dense mounds.
THRYSIFLORUS VAR. REPENS E. ‘CREEPING BLUE BLOSSOM’. Mid-blue.
RHODODENDRON E. Hardy Hybrids and Yakushimanum Hybrids usually flower profusely, well into June.

Low growing varieties.

‘BLUE DIAMOND’ E. Rich violet-blue.
‘ST MERRYN’ E. Lilac blue flowers.
AZALEA ‘BLUE DANUBE’ E. Blue to purple flowers smother the low plants.
ROSMARINUS OFFICINALIS E. ‘ROSEMARY’. Small blue hooded flowers.
- ‘PROSTRATUS GROUP’. Whorls of purple-blue to white flowers in late spring.
SYRINGA (Lilac) ‘FIRMAMENT’. Sky blue and scented. Flowers early.
‘KATHERINE HAVEMEYER’. Deep purple lavender; double. Scented.
VINCA MAJOR E. ‘PERIWINKLE’. Bright-blue flowers until June.
- ‘VARIEGATA’ E. Similar flowers. Leaves blotched creamy white.
MINOR. Mauve flowers up to 3cm across. Small leaves.
- ‘ARGENTEOVARIEGATA’ E. Pale mauve flowers. Leaves cream and green.
- ‘ATROPURPUREA’ E. Flowers deep plum or vinous purple.

Climbers

CEANOTHUS FORMS E. Various shades.
CLEMATIS - Large Flowered Varieties

‘BARBARA JACKMAN’. Soft petunia blue with plum coloured bar.
‘FIREWORKS’. Large blue flowers with deep petunia-red bar.
‘LASURSTERN’. Lavender blue.
‘MRS. CHOLMONDELEY’. Lavender sepals tipped purple.
‘VYVYAN PENNELLl’. Violet blue shaded with crimson; double flowers.

Small Flowered Varieties

ALPINA ‘FRANKIE’. Pale blue flowers freely produced.
- ‘HELSINGBORG’. Deep purple blue; flowers freely.
MACROPETALA. Deep lavender blue, small nodding flowers.
LONICERA PERICLYMENUM ‘BELGICA’. Pale rose-purple and yellow.
WISTERIA SINENSIS. Mauve or deep lilac.

Perennials

AJUGA IN VARIETY. All have short spikes of blue flowers May/June.
AUBRIETA. Light lavender blue. Dark blue. Purple. Provide a wonderful display of flowers until May on flat cushions of foliage.
BRUNNERA MACROPHYLLA. 45cm. Perennial “Forget-me-not”.
GERANIUM RENARDIIi. 20cm. Pastel lavender veined violet purple flowers.
LITHOSPERMUM DIFFUSUM ‘HEAVENLY BLUE’ E. Caerulean blue.
NEPETA FAASSENII E. ‘CATMINT’. 30 cm. Lavender blue all summer.
PULSATILLA VULGARIS. ‘PASQUE FLOWER’. Violet purple bells, golden anthers.
TANACETUM IN VARIETY.
VERONICA GENTIANOIDES. 60cm. Racemes of deep blue April/May.
- ‘PALLIDA’. 60cm. Light blue flowers.
- PEDUNCULARIS ‘GEORGIA BLUE’. Deep blue flowers in early spring to summer.
SPICATA ‘ROYAL CANDLES’. Strong, deep blue spires of flower, May-July, on sturdy stems.
TEUCRIUM ‘CRATER LAKE BLUE’. 35cm. Ultramarine blue flowers.
VIOLA ‘MOLLY SANDERSON’. 10cm. Midnight black flowers with tiny golden eyes.