What causes rose balling? Rose balling is an annoyance that dominates in a damp, cool summer exactly like the one we endured in sunny Derbyshire in 2012. Flower buds develop normally but fail to open fully. Wet weather saturates the outer petals and when the sun finally puts in an appearance and scorches the flower dry, the outer petals are fused together preventing full opening. These fused petals dry to a crisp, brown appearance.
Rose balling can be a problem if you've planted roses in a partially shaded site, and you've got a penchant (as I) for roses with a multitude of thin petals. Rosa Eglantyne and Geoff Hamilton are particularly vulnerable in my garden, whilst my peonies and camellias appear to be thus far unaffected. Clearly the site is the predominant problem.
Standard advice seems to be pruning to open up a lovely goblet shaped bush thus enabling good air circulation and rapid drying of the flower buds after rainfall; watering in the evenings only (laughable advice last summer); removing balled buds promptly before grey mould sets in and infects both host and nearby plants with a whole new set of problems; and rather drastically, removing or cutting back overhanging shrubs and trees.
Reading this advice last year on the RHS website finally prompted me to tackle my knackered old Warwickshire Drooper plum tree, stalwart of hundreds of jars of my world famous spiced plum chutney (thank you Delia.) More of that in a forthcoming post.