My beautiful lawn died within one week, so did my neighbors’ on either side as well as the neighbor to my rear. The whole lawn, not just small areas. In addition to the dead lawn there seem to be some sort of fungus/blight attacking the leaves of the cosmos, coneflowers and peonies. The bottom leaves turn brown/black, then the plant dies. In early spring after the forsythia had finished blooming I noticed some leaves were curling and these I cut off and disposed of. I might mention that my friends in Scarborough has had the exact problem with their lawn. I live in the City of Toronto Zone 6. The front lawn does not have the problem.
I desperately need your help, I do not want to reseed if there is fungus in the soil.
Thank you for contacting the Toronto Master Gardeners with your questions regarding your lawn and plants. Many lawns in the Toronto area experienced stress this summer with drought conditions. However, it seems that the issue with your back lawn has happened recently and quickly, which is understandably distressing. The question is whether this is related to a pest or disease. Since this has happened so quickly and effects your neighbour’s lawns as well, the possibility of some other factor such as a chemical application is also worth considering. We suggest you begin by examining the grass – dig up and look under a section of turf. Inspect the underside for signs of insect pests. Chinch bugs can cause damage to large swaths of turf but typically do this in dry, hot summer conditions and it happens in patches over time. More information can be found at this website.
Also inspect the grass for signs of disease – some fungal diseases will have telltale signs of spores on the grass blades. Please feel free to submit photos to our site. However, it may be best to contact a lawn-care expert for their opinion. The Professional Lawn Care Association of Ontario provides an overview of lawn diseases with pictures and management strategies and we have attached the link for you below.
Landscape Ontario is a good source of information regarding Lawn-care professionals in your area https://landscapeontario.com
At this time of year, with cooler, wetter conditions, diseases such as blights, rot and mildews can take hold in our plants. Please feel free to submit photos to our site and we can do our best to identify the disease your plants are experiencing. However, as autumn progresses and plants are naturally dying back this may be more difficult. The best path forward is to trim and clean up all the diseased-looking plant material and dispose of it in the City yard waste. Keep this material out of your compost bin and garden beds to prevent the spread of disease. The Missouri Botanical Garden has a helpful page on common plant pests, including biotic diseases and we have attached the link below. The University of Minnesota provides some general tips on cleaning up the garden in the fall to prevent pests and diseases next year and we have attached the link for you as well.
We hope this information is helpful in resolving your lawn and garden concerns.