Feeding is the lever most people miss. Black spot loves soft, sappy growth, and high-nitrogen fertiliser produces exactly that. Go balanced, with extra potash in spring and again after the first flush. Tougher leaves mean less to infect. Then look at what sits against the base. Fine compost or grass clippings turn every shower into a splash zone flinging spores onto the lowest leaves. Chunky bark or gravel does the opposite. Water early. Base watering is right, but mornings mean any leaf that does get wet dries before dark. Be honest about your worst bush, too. In Harvey's wet winters some cultivars will always struggle. If one plant gets stripped bare every year while its neighbours are fine, that's the plant, not your routine. Replace it with a resistant variety and you've fixed something no spray can. Wipe your secateurs between bushes as well.
Feeding is the lever most people miss. Black spot loves soft, sappy growth, and high-nitrogen fertiliser produces exactly that. Go balanced, with extra potash in spring and again after the first flush. Tougher leaves mean less to infect. Then look at what sits against the base. Fine compost or grass clippings turn every shower into a splash zone flinging spores onto the lowest leaves. Chunky bark or gravel does the opposite. Water early. Base watering is right, but mornings mean any leaf that does get wet dries before dark. Be honest about your worst bush, too. In Harvey's wet winters some cultivars will always struggle. If one plant gets stripped bare every year while its neighbours are fine, that's the plant, not your routine. Replace it with a resistant variety and you've fixed something no spray can. Wipe your secateurs between bushes as well.
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