Plant of the month for June: Harlow Car hybrid primulas

With blooms of acid-bright yellow, mauve, orange and pink, no one could call the Harlow Car hybrid primulas subtle, but their swathes of colour will brighten up any bog garden in June

Harlow Carr primulasBeside the cool, lush Streamside, full of fresh green ferns, spikes of candelabra primulas send up tier upon tier of blooms in acid-bright yellow, orange, pink and mauve from April to June: it's not subtle, but it will make you smile. These hybrids are from Harlow Carr where they thrive in the boggy ground. Look away now if your soil is well-drained and dry: in gardener's speak, these plants like their feet wet.

Harlow Car hybrid primulas (and that is not a spelling mistake – they are Harlow Car, not Harlow Carr) appeared when Primula bulleyana AGM, P. beesiana AGM, P. japonica and P. pulverulenta AGM were planted in close proximity to one another many decades ago, when the garden belonged to the Northern Horticultural Society. They cross bred and popped up all over the garden, often in full sun. When the plants first started hybridising to the extent that they were recognised (the first record of seed being available was in the early 1960s) they were recorded with the single ‘r’ spelling, and it’s stuck ever since.

They may look a bit messy in spring, before the flowers arrive: you can tidy them up a touch, but these are semi-evergreen plants, so give them space and they will reward you with a riot of colour. And we only divide them when areas become congested or if one colour becomes too dominant. The colours are really mixed, but we are always on the lookout for a deep red so keep your eyes peeled!

At Streamside they grow alongside Lysichiton americanus, Athyrium niponicum var. pictum AGM, Primula florindae AGM and Matteuccia struthiopteris AGM. You can enjoy a similar splash of colour yourself - you can buy them from our plant centre to recreate a bit of Harlow Carr at home. Each plant has a height and spread of 60cm x 30cm but the only way to display them is in a group, drifting alongside other woodlanders with a preference for the wet: Iris sibirica, Ligularia and hostas, for instance.  Make these primulas the centrepiece of a bog garden and you're on the right track. Think dappled shade and neutral to acidic soil, too, for the best possible display.

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