Fungus - Ask Extension
We live in Silver Spring. My husband put a garden in in our front lawn. Last year all the plants grew fungus on them and we had to pull all of them up...
Knowledgebase
Fungus #925826
Asked March 11, 2026, 8:13 AM EDT
We live in Silver Spring. My husband put a garden in in our front lawn. Last year all the plants grew fungus on them and we had to pull all of them up. In general, the only plant that has survived is a rosemary plant. What might this fungus be and what can we do to get rid of it and make this a healthy garden so we can plant in it again? I don’t know if it helps to know that we have also had a horrendous time trying to grow grass. Basically our backyard and our front yard had turned into mud pits over the last couple years.
Montgomery County Maryland
Expert Response
We aren't able to diagnose the fungal issue without images of the symptoms, but one common fungal infection is powdery mildew. While powdery mildew is often host-specific (only infects one type of plant, or a group of related plants), it can seem to spread across multiple plantings because different species of powdery mildew create similar symptoms and can begin infections around the same time of year. Powdery mildew thrives on high humidity and poor air circulation, so plantings that are crowded (or which are near walls or solid fences that limit airflow) may contract outbreaks at certain times of year (often spring and fall).
Turfgrass challenges are a separate issue, and we'd need more information to be able to narrow-down likely causes for failure. We are getting close to publishing a bunch of revised lawn care pages, but in the meantime, you can browse the linked pages for helpful recommendations. (The new pages will not have changes to the basic care tips, but they will be consolidated content and have more thorough info. with more photo examples.) How a lawn is cared for seasonally greatly depends on what type you're growing: cool-season (tall fescue, typically) or warm-season (zoysia). Tall fescue is usually the best choice for Maryland lawns, and it requires full sun (or at least a half-day of sun, once trees leaf-out) to thrive. Annual overseeding, core-aerating (if foot traffic is heavy or regular), and fertilizing help it remain vigorous and better able to out-compete weeds and prevent erosion or bare spots.
Are the failing areas of lawn near mature trees, whose canopy shade and/or roots are competing with the grass? If so, consider using alternative plantings in those areas, as the trees will win and the grass will continue to struggle. If the yard is full sun, one good first step is to have a laboratory soil test taken to learn what the nutrient and acidity (pH) conditions are, to better know what might need adjusting to help grass thrive. We can help to interpret the test results if desired.
If you start to see concerning symptoms on any new plantings this year, feel free to share photos with us and we can try to diagnose the problem. Perennials with powdery mildew are usually fine the following year when they start regrowing, and do not need to be removed; annuals (zinnia, petunias, etc.) are only grown for one year, so if they get too damaged by mildew or another disease, removal and replacement is sensible.
Miri
Turfgrass challenges are a separate issue, and we'd need more information to be able to narrow-down likely causes for failure. We are getting close to publishing a bunch of revised lawn care pages, but in the meantime, you can browse the linked pages for helpful recommendations. (The new pages will not have changes to the basic care tips, but they will be consolidated content and have more thorough info. with more photo examples.) How a lawn is cared for seasonally greatly depends on what type you're growing: cool-season (tall fescue, typically) or warm-season (zoysia). Tall fescue is usually the best choice for Maryland lawns, and it requires full sun (or at least a half-day of sun, once trees leaf-out) to thrive. Annual overseeding, core-aerating (if foot traffic is heavy or regular), and fertilizing help it remain vigorous and better able to out-compete weeds and prevent erosion or bare spots.
Are the failing areas of lawn near mature trees, whose canopy shade and/or roots are competing with the grass? If so, consider using alternative plantings in those areas, as the trees will win and the grass will continue to struggle. If the yard is full sun, one good first step is to have a laboratory soil test taken to learn what the nutrient and acidity (pH) conditions are, to better know what might need adjusting to help grass thrive. We can help to interpret the test results if desired.
If you start to see concerning symptoms on any new plantings this year, feel free to share photos with us and we can try to diagnose the problem. Perennials with powdery mildew are usually fine the following year when they start regrowing, and do not need to be removed; annuals (zinnia, petunias, etc.) are only grown for one year, so if they get too damaged by mildew or another disease, removal and replacement is sensible.
Miri
