Roses are relatively easy to care for; however, once black spot takes hold, it can be a nightmare to keep the plant healthy. Considered the most significant rose disease nationwide, black spot reveals itself as dark, rounded leaf spots with feathery, irregular borders. Unlike some common fungal diseases, black spot only appears on the topsides of rose leaves and stems, never on the undersides of leaves.
As the disease progresses, leaf areas surrounding dark spots become yellow. The yellow regions then expand to cover the entire leaf. Infected leaves eventually drop off plants completely, leaving your roses weakened, stressed and vulnerable. Taking to his TikTok account @themediterraneangardener, gardening pro Michael shared “how to deal with black spot on roses”, which he noted as being “the most serious disease for roses”.
Michael pointed out that “the best thing you can do” for roses in this situation is to “pick them off”, which should take no more than five minutes. He’s instructed: “Remove any affected leaves as they carry the black spot fungus”.
For those doing this with a pair of secateurs, remember to give them a good clean after to stop the spread of the disease.
Alternatively, you can just pull off the leaves in the opposite direction to the growth to “easily remove them by hand”.
Michael pointed out that if there are any fallen infected leaves, they will need to be picked up to avoid the disease spreading.
Gardening guru David Domoney also recommends this method for removing black spot disease from roses; however, there’s one thing he highlighted.
He said: “Pick off infected leaves when first seen to help minimise their spread. Do this only if you’ve had a definite diagnosis that the blotches are black spot. This is because removing leaves can limit the plant’s ability to grow well.”
To reduce the likelihood of the disease coming back, make sure to mulch to around three inches, locking in water and suppressing weeds.
Gardening expert David Marks from Garden Focused explained that the aim of mulching the soil around the rose bush is to trap any remaining leaves where they are. The spores on fallen leaves re-infect the plant when raindrops fall on the leaves and the spores splash onto new growth.”
He noted that gardeners should use a layer of cardboard as mulch to prevent this from happening.
As well as trapping the leaves onto the soil surface, the cardboard will help retain moisture in the soil below. Over the year, it will also rot down and provide a small amount of fibre for the soil.
