Growing Primulas

Primulas are a joy in the spring garden, and some will continue through the summer and into early autumn. They are herbaceous perennials, much more refined than the bedding polyanthuses, and when in the conditions they like will come back for many years.

Native primulas are very easy-going, and lovely in wild gardens, woodlands and meadows. The Asiatic primulas are fussier, liking reliably damp, acid to neutral soil; they are good in bog gardens, or on stream or pond banks, and are brilliant for bringing rich colour to a shady area. There are other lovely primulas, too, good in borders, and all love a deep, humus-rich, reliably moist, even wet, usually acid to neutral soil – a treat for those whose soil lies heavy and wet, and who sigh when ‘well-drained soil’ pops up on the website. All the ones discussed below are fully or very hardy.

Native primulas

We are all familiar with lovely, delicately scented, native primroses (Primula vulgaris AGM) and many of us remember when the meadows were full of fragrant cowslips (Primula veris AGM) with their semi-evergreen rosettes of crinkly leaves. These are really beautiful wildflowers, and true harbingers of spring – primroses in the hedgerows and under walls and ditches, and deep yellow, scented cowslips in the meadows. They are both supposed to like any moist but well-drained soil, but although my gravelly soil drains like a sieve, the primroses and cowslips are thriving and seeding about.

Primroses can come into bloom very early in the year, and keep going until May; they look particularly lovely with sweet violets (Viola odorata) and the hartstongue fern (Asplenium scolopendrium). Cowslips now appear as early as the end of March in milder areas, and persist through April and into May, studding the grass with their rosettes of pale green leaves and charming, rich yellow flowers with orange bee-guides. They overlap with that other pretty native, lilac-blue lady’s smock or cuckoo-flower (Cardamine pratensis) and the deep blue speedwells, which set them off to perfection.

Primroses and cowslips both tolerate some exposure, in full sun or partial shade. They are valuable early flowers for pollinators, both for nectar and pollen, and are a food plant for caterpillars. Primrose flowers are edible, and lovely in salads or candied to decorate puddings and cakes. And if you have a lot of cowslips, you can even make lockdown wine out of the flowers – and very good it is.

The semi-evergreen, primrose-scented true oxlip (Primula elatior) prefers alkaline soil, and is not native to Ireland, though long established here; it’s a plant of open woodland and wet meadows grazed by cattle (it loves cowpats). It’s like a cowslip, but a paler yellow with a deep yellow eye, and the flowers tend to face in the same direction, instead of all round the stem. It flowers from April to May, and is particularly lovely in a light woodland planting. The true oxlip can be confused with the false oxlip, a natural hybrid of the primrose and cowslip, and native in isolated places, particularly in the Burren; it has tapering, crinkly leaves like a primrose, and the flowers are like those of the cowslip, but larger, and a paler yellow, with an orange throat.

There is a new cowslip cultivar called Cabrillo, with even brighter yellow flowers, which likes meadows, borders and light woodland, and grows in full sun or partial shade in heavier, moisture-retentive soil, alkaline to neutral preferred.

All these can be grown as part of a spring planting scheme, with brunnera, forget-me-nots and early spring bulbs like snowdrops and scillas, and are also lovely with the green- or primrose-yellow-flowered hellebores.

Candelabra primulas

Next come the candelabra primroses, with their layered tiers of bright flowers. These really do need moist, acid to neutral soil, even poorly drained or boggy soil, and do better in partial shade, although they will thrive in full sun provided the soil is really damp, even wet – perfect for bog gardens and reliably damp corners of the garden, backed by moisture-loving ferns.

Bee’s primrose (Primula beesiana AGM) has a rosette of light green, primrose-like leaves; beautiful tiers of rose-purple flowers with yellow eyes on 20”/50cm stems appear from late spring and through the summer. It likes sheltered, partial shade, but will grow in full sun if in reliably damp or boggy soil. It is happy in a clayey, loamy or peaty soil and hates drying out. No cutting back is needed. Lovely with moisture-loving ferns, and if planted at a pond’s edge, the native yellow water lily (Nuphar lutea) will pick up the yellow eye of the primula.

Bulley’s primrose (Primula bulleyana AGM) is taller at 2’/60cm, with tiers of rich orange-yellow flowers opening from orange-red buds from March to June over a rosette of mid-green, semi-evergreen, primrose-like leaves. It likes loamy, neutral to acid, reliably damp or poorly-drained soil, and is a little more robust than Bees’ primrose, tolerating some exposure. Cut back after flowering. It looks striking with the water-iris, Iris laevigata, and also looks well with toning geums in a moist soil.

The long-lived, versatile mealy primrose (Primula pulverulenta AGM) is perhaps the easiest to grow, and bears magenta flowers with a deeper red or purple eye in distinct tiers on mealy, white stems in late spring to early summer. It’s a robust plant, tolerating exposure, and can grow up to 3’/90cm tall, with a spread of 18”/45cm. It likes a loamy, poorly drained, acid to neutral soil and partial shade – ideal for a bog garden. Cut back stems after flowering. Lovely with Bowles’ golden sedge and ferns.

Drumstick primroses

The lightly fragrant drumstick primroses are perfect for growing in groups at the front of the border, although, like most non-native primulas, they need a loamy, humus-rich, reliably moist, acid to neutral soil; they will tolerate a well-drained one, but can also be grown in a bog garden, or in a well-watered pot. Above a rosette of crinkly leaves, mealy underneath, the little bell-shaped flowers form a tight ball at the top of the strong, slightly mealy stem – hence the name ‘drumstick’. They are quite tough, tolerating some exposure, and will self-sow where happy, forming a drift. To prolong flowering, cut flower-stems to the base when they’ve gone over – unless you want them to self-sow; they are particularly attractive in drifts.

The species drumstick primrose (Primula denticulata AGM) has a tight ball of pale pinkish-purple flowers, up to 3/4”/18mm wide, with a tiny golden eye. The flower stems are up to 20”/50cm tall, sometimes smaller, with a similar spread, over a rosette of ovoid, crinkly, mid-green leaves. It’s a low-maintenance plant when established, and will flower from May right through the summer. Good with spring bulbs that like the same conditions, especially summer snowflakes (Leucojum aestivum).

The lovely white form, the white drumstick primrose (Primula denticulata var. alba) has paler leaves, and pure white, bell-shaped flowers with a golden-yellow eye, forming a tight sphere at the top of the strong, mealy stem from late March to May. It’s a little smaller than its ruby-coloured parent, 1’/30cm in height and spread. Cut back to the base when the flowers go over. Good with moisture-loving ferns and yellow spring flowers reflecting the golden eye, or underplanting shrubs.

Japanese primroses

Primula japonica is a smaller, very versatile primrose, 18”/45cm tall, good in a sheltered border in loamy, moist, even poorly-drained, acid to neutral soil. It likes partial shade, but will tolerate full sun in reliably damp soil. The bell-shaped flowers, in whorls up the stem, appear in late spring and early summer. A good plant for a bog garden or damp pond edge, but also in damp borders. Very good in large drifts, or with smaller ferns. More decorative, named forms are usually grown.

Primula japonica Miller’s Crimson AGM is a beautiful cultivar with deep crimson flowers with a deeper crimson eye growing in up to six whorls at the top of the stout stem from late spring to early summer. Grow this in loamy, moist to wet, acid to neutral soil in partial shade, and it will seed about mildly, and naturalise – it’s particularly lovely in drifts. It’s a good plant for pollinators, and 20”/50cm in height and spread.

Primula japonica Postford White AGM has lightly fragrant, white flowers with a yellow eye in up to six whorls at the top of the stem above a rosette of pale green leaves. It likes damp, even poorly drained, loamy soil, and partial shade, but will tolerate full sun in reliably damp soil. It’s a vigorous cultivar, and will seed about and naturalise where it’s suited. It flowers from April to June, is 18”/45cm tall, and will spread to 1-2’/30-60cm. Very attractive with moisture-loving small ferns and yellow flowers to pick up on the golden eye.

Other superb primulas

The round-headed Himalayan primrose (Primula capitata) is a charming little plant, with a semi-evergreen rosette of toothed, mealy leaves, silvery underneath. From May to early autumn, tiny, deep purple, tubular flowers make a small, flat rosette at the top of the 1’/30cm, mealy stems. Another primrose needing consistently damp, even poorly-drained, loamy, humus-rich, acid to neutral soil, it should be grown in partial shade, and is very attractive at the front of an open, north-facing border or in a partially shaded rock garden. Super-hardy, it does not need cutting back. Lovely with contrasting, linear foliage and low, pale yellow flowers.

Finally, a very fashionable primula: Vial’s primrose (Primula vialii, AGM) is a most unusual primrose with the typical primula rosette of heavily veined, longer-than-usual leaves, but very different flowers. In June and July it bears a conical spire of red buds which open from the base of the spire into pale blue-violet, bell-shaped flowers, nearly ½”/1cm across and with a red tip, on erect stems 16”/40cm tall. It spreads to 1’/30cm. It loves a reliably moist, loamy or peaty, humus-rich, acid to neutral soil, in full sun or partial shade. It is good with small hostas or ferns, over which the flower-spires rise, giving a splash of bright colour, or in a woodland or shrub border, at the edge of a bog garden or in damp soil beside a pond. There is also a spring-flowering white form, Alison Holland, with white flowers opening from a spire of green buds, which can really light up a shady spot.