Black spot is a severe fungal disease that causes roses to develop black patches on their leaves, which eventually turn yellow and fall off, but natural solutions can help prevent it
Angela Patrone Senior Lifestyle Reporter and Ellen Jenne U35 Spare Time Writer
11:51, 15 Jan 2026
Gardening enthusiasts should note that roses need safeguarding not just from January's cold temperatures but also from diseases such as black spot, which flourishes in damp weather conditions. Black spot is a serious fungal infection that causes roses to develop dark patches on their foliage, which subsequently turn yellow and drop off, reports the Express.
The disease's spores are usually carried by wind but require moisture to germinate, making wet and muddy conditions especially dangerous for your garden. Whilst black spot is unlikely to kill roses completely, without treatment it can considerably weaken the plant, diminishing its prospects of surviving winter.
It can also restrict a rose plant's growth and impair its capacity to produce blooms, leaving your garden empty when summer arrives. Nevertheless, experts at Dammann's Garden Company have stated that preventing black spot is remarkably simple and doesn't necessitate harsh chemicals.
Remarkably, natural solutions such as baking soda can prevent the disease by establishing an alkaline environment on the surface, disrupting spore development. Even ordinary white vinegar, the type you'd put on chips, can help tackle black spot disease.
Its acetic acid component, which possesses mild antifungal qualities, can effectively eliminate spores. The specialists explained: "Toxic solutions might be effective, but they are damaging to your garden and soil and should be used as a last resort.
"Vinegar and baking soda are a great way to safely combat the growing fungus by changing the pH balance. A mixture of cow's milk and water will do the same thing."
The proteins present in cow's milk have antifungal qualities whilst also acting as a surfactant, meaning they'll both eliminate spores and stop them from developing on leaves.
Neem oil is another highly effective solution, forming a protective layer around roses. This coating makes it difficult for spores to spread and disrupts any that have already taken hold on the plant.
The experts explained: "This is a commercial oil that is derived from evergreen neem trees, and works great as a natural fungicide, preventing the Black Spot-causing fungus from thriving. Make sure you follow the directions on the container to mix the oil to the right concentration."
If your roses are currently healthy and you're simply worried about possible infection, the best prevention approach is to keep your blooms dry.
Overgrown roses have a tendency to trap moisture and limit air flow, creating perfect conditions for disease to take hold. Make sure you prune your roses at the correct time, which is usually during February or March.
Furthermore, remove any debris or fallen leaves around your roses. Spores can easily spread through dropped foliage, which holds significant moisture.
Winter mulching of your roses is essential to provide them with adequate water during the cold weather, as well as to suppress weeds and prevent the spread of spores. The experts advised: "Add a layer of mulch to the soil to keep the moisture locked in despite the better airflow, simultaneously keeping the roots healthy and suffocating developing weeds."