How to treat blackspot on roses

Blackspot is among the most common rose problems, but there are ways to control it, says HANNAH STEPHENSON

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YOUR roses should now be bursting into bloom, adding heady fragrance and rich colour to your garden - unless the dreaded black spot has done its worst.

If you see dark brown or black blotches appear on the leaves of your roses before turning yellow and falling off the plant prematurely, they are likely to have been infected by this fungus.

The spots usually appear on the leaves from early summer onwards and spread rapidly. Damp weather can make the problem worse and badly affected plants can shed all their leaves, which can weaken the rose.

Black spot (Diplocarpon rosae) overwinters on fallen leaves and also in dormant infections on young stems and buds, producing spores in the spring to infect young foliage.

But there are many things you can do to prevent and treat it, says Neil Miller, head gardener of Hever Castle & Gardens in Kent, which has more than 5,000 roses in bloom in June and July and is staging Hever In Bloom over two weeks in the summer, featuring garden tours, flower arranging workshops and other events.

GOOD GARDEN HYGIENE