Exiles Forum

Lisburn, Co. Antrim, Northern Ireland




Divide and conquer

MANY spring flowering perennials can be divided and replanted, a couple of weeks after their blooms have stopped.

Of course you don't need to do this with all of them, just the ones which are getting too big for their boots or didn't flower as well as usual. Older Primula, Doronicum, Aubrieta, Dicentra are but a few candidates. How do you divide? Well if you've a plant with fibrous roots, maybe may need two forks driven down back to back in the centre of the clump, then carefully prised apart.

For those perennials with fleshy crowns, dig up the whole mass and use a sharp knife to cut it. Each new section needs to have a bud and plenty of roots to ensure success.

Iris are one group of perennials that especially benefit from division, as they grow from their edges leaving a woody old interior. You really should do this every three or four years, again a couple of weeks after flowers have finished. Dig up the entire clump, cutting off fresh pieces 4-6 inches long with good roots and leaves. Prune off the. top of the leaves too, as this stabilises the new plant. Then set the new rhizome on good soil and compost, which must be well drained. Iris do best on dry soil, and the rhizome shouldn't be completely covered - just ensure the roots are well anchored.

Keep an eye on feeding your later flowering herbaceous stock like Dahlias; they are very hungry plants at this tune of year.

There's a few local gems to look out for, now in flower. The Roses 'Sam McGready' and the compact, double scarlet flowered 'City of Belfast' (look out for them in Sir Thomas & Lady Dixon Park ) and the Aconitum 'Newry Blue', not to mention the Escallonia 'Donard Seedling', 'Donard Radiance' and 'Pride of Donard', originally cultivated on the sunny slopes of Slieve Donard near Newcastle.