Latest news with #Diplocarponrosae
Business Mayor
23-05-2025
- Health
- Business Mayor
Growing roses? Here's how to deal with the most common problem gardeners face
For free real time breaking news alerts sent straight to your inbox sign up to our breaking news emails Sign up to our free breaking news emails Just as your roses reach their peak, a common fungal foe may be lurking, ready to sabotage their vibrant display. Black spot, easily identified by the dark brown or black blotches that appear on leaves before turning them yellow and causing premature leaf drop, can quickly spread, especially in damp conditions. This infection can significantly weaken the plant, sometimes leading to complete defoliation. The fungus responsible, Diplocarpon rosae , survives the winter on fallen leaves and within the stems and buds of the rose plant itself. Come spring, it releases spores that infect the new growth, perpetuating the cycle. If you notice the telltale signs of black spot, swift action is crucial to protect your roses and ensure a beautiful bloom throughout the season. Black spot can been spotted on the leaves of your roses (Alamy/PA) 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. The Gardens and is staging Hever In Bloom over two weeks in the summer, featuring garden tours, flower arranging workshops and other events. Here are Mr Miller's top tips: Good garden hygiene 'Roses tend to get black spot once the rain comes in the summer – it encourages the spread of this fungal disease. It can spread from year to year. The yellowed leaves fall to the ground and the spores stay in the earth and can transfer to new rose growth the following year. Read More Inflation Fears Explain A Seeming Housing Market Mystery 'Practising good garden hygiene is the best way forward – collecting and incinerating fallen leaves in the summer to prevent the spread, and cutting out any diseased stems. 'Keep clearing any fallen leaves, ensure you cut out any dead wood, keep dead-heading the blooms and mulch every year.' Remove diseased leaves 'You can pick off the spotted leaves (wearing gloves) to remove the source of reinfection. And remember, each fallen leaf must be removed from the ground – ensure you collect every one. It only takes a leaf or two, over winter, to keep the problem going into the following year.' Let air circulate Miller says: 'When you plant your new rose bushes make sure they're planted in an area where air is not restricted – you need a free-flow of air around your bush.' Think organic Miller advises rose growers to try to incorporate organic measures like apple cider vinegar spray, or even a milk spray and lemon juice. Neil Miller, head gardener at Hever Castle & Gardens (Hannah Stephenson/PA) 'Fungus tends not to enjoy being sprayed with apple cider vinegar, so that's good option – it's also safe for the all-important bee population.' Feed them 'Another key to promoting healthy roses is to feed them with a granular slow-release food at the start of the season and after the first flush in July. Take your feed and draw a little circle with it around the base of the plant, make sure the feed doesn't scorch the leaves,' he says. Use a mulch If you mulch around your roses it will help stop the spores from splashing up from the ground. Choose disease-resistant varieties 'Rose selection is very important. So when you're leafing through your bare root catalogue this autumn, look out for rose species that are either specifically bred to be disease-resistant like the peach shrub rose 'Dame Judi Dench' (David Austin) or select the older gallica or rugosa varieties which tend not to suffer from black spot,' Miller advises. 'In the Rose Garden itself we have removed plants over the years which have been particularly susceptible to disease and have selected more modern varieties that repeat bloom throughout the summer, rewarding visitors with an incredible display. 'Among our current favourites are 'Absolutely Fabulous' – a wonderful yellow rose that looks healthy year on year, 'Lucky', and 'Audrey Wilcox'. 'We removed 'Rhapsody in Blue' two summers ago and planted the more resistant, and floriferous 'Timeless Purple' in its place. 'Timeless Cream' has also performed very well for us over the past couple of years.' However, the RHS warns that the fungus is genetically very diverse and new strains arise rapidly, which means that the resistance bred into new cultivars usually fails to last because new strains of the fungus arise to overcome it. Hever In Bloom runs from 23 June – 6July.
Daily Record
20-05-2025
- Health
- Daily Record
Gardeners warned to complete one task or risk plants becoming 'diseased'
Black spot is a fungal disease that causes dark spots to appear on rose leaves, often with yellow halos. It can lead to premature leaf drop, which weakens the plant Garden enthusiasts have been advised to carry out a straightforward task immediately to prevent their plants from suffering damage. If you're nurturing roses in your garden, it's crucial to take note, as this problem is quite prevalent. You might have spotted black spots appearing on your roses while tending to your garden and, if you do, immediate action is required. These spots are an indication of a fungal disease known as Diplocarpon rosae, which causes dark spots surrounded by yellow halos to appear on rose leaves. This issue can result in premature leaf shedding, thereby weakening the plant. Over time, black spot can also make roses more vulnerable to other diseases and winter damage if not addressed. However, a gardening expert named Michael, who goes by the handle themediterranean gardener on TikTok, recently shared a solution to this problem. According to him, the most effective thing you can do is pluck them off. He emphasised the need to remove any affected leaves immediately, and the reason for this is straightforward. If you undertake the task using secateurs, he stressed the importance of washing them afterwards. This step is crucial to prevent the disease from spreading to other plants. However, he also pointed out that you can simply pull them in the opposite direction of growth for easy removal. It's then necessary to destroy anything you remove from your plants - don't discard them in the compost heap. If you're struggling to identify black spot on roses, the tell-tale signs include small dark, rounded marks on the leaf's upper surfaces, frequently surrounded by a yellow perimeter. The afflicted spots often expand and fuse together, causing leaves to turn yellow and fall prematurely, with young stems also at risk - vigilant plant inspection is key. Black spot disease propagates through wind and water, posing a risk to neighbouring roses; therefore, precise actions are recommended as preventative measures. Strategies for thwarting black spot include applying fungicides in the spring to bolster plant defence, spaciously placing roses for enhanced air flow, and ensuring sufficient sunlight exposure to expedite post-watering drying. An additional protective measure involves mulching to retain soil moisture and stifle weeds, which is part of a comprehensive approach to managing black spot. Gardener's World provides a grim picture of the impact of black spot, explaining: "Leaves are disfigured by poorly defined purple-brownish-black blotches. The leaves then turn yellow and fall. Stems might also be affected. "Pick up and destroy fallen leaves. When pruning, cut out any stems with black spot on. "In late-winter, spread a thick layer of mulch around the base of the affected plant to prevent rain splashing soil-borne spores on to new spring growth. Grow rose varieties that are resistant to black spot – these are suggested in the catalogues of specialist rose growers." Discussing the use of chemicals to tackle the issue, the magazine adds: "Spray against black spot with a fungicide. Follow the instructions, treating the new foliage in early spring, with further sprayings at regular intervals through the season." By following these straightforward tips, you can take steps to shield your plants. Bear in mind that spotting the problem early is crucial.
