The most common lawn diseases are dollar spot, snow mold, rust, red tip, and root rot.
Dollar spot can be recognized by light-colored spots about 1 to 3 cm in size. In the morning, when there is dew, they usually have a white mycelium.
The causes are high temperatures of 25-30 °C and cool nights with dew formation. Also, dryness of the soil and lack of nutrients.
It is prevented/controlled with sufficient nutrient supply in summer and avoiding drought stress even on partial areas. Watering should be abundant, but not in the evening. Lawn thatch is removed by scarification.
Recognizable by gray/brown moist patches, mostly rotten, ranging in size from 5 to 25 cm. Marginal areas are typically brown and have gray or pink mycelium.
The causes are low temperatures (0-8 °C) and high humidity. As the name suggests, it occurs mainly under snow cover.
It is prevented/controlled by avoiding water stagnation and high humidity. Timely scarification and sanding for sufficient aeration and fall fertilization with calcium and magnesium as needed.
Lawn rust can be recognized by yellow-brown or black pustules on the leaves, yellow nests, and dusty spread of spores.
The causes are persistent warm weather at 20-30°C and nutrient and water deficiency.
It is prevented/controlled by even nutrient supply (fertilization), good aeration, and reducing shade plants. Always keep the soil sufficiently moist, while the grass should dry out as quickly as possible (water in the morning).
Red tip can be recognized by irregular, overlapping yellowish spots. A red structure grows on the infested leaves and, in high humidity, a pink mycelium forms on the leaves.
It occurs mainly in summer and autumn, at temperatures of 15-20 °C, high humidity and undernourished grasses.
Red top is prevented/controlled by immediate fertilization with 4-6 g/m² nitrogen. On the positive side, affected grasses do not die but sprout again.
Root rot can be recognized by dark, brown, irregular spots. The grasses appear slimy and rotten, the roots are brown and destroyed, and can be easily pulled out.
It often occurs in new plants or reseedings. It attacks weakened grasses after drought, with persistent moisture and waterlogging. In addition, nutrient deficiencies and a very low pH value promote infestation.
It is prevented/controlled by reducing moisture and ensuring good aeration by scarification or aeration. Sufficient nutrient supply is also important.
The most common weeds are dandelion and clover.
Dandelion is controlled by cutting the flower, stinging it or destroying it: chemical means, pets (rabbits, guinea pigs, chickens). If the lawn is completely overgrown, the last 30-50 cm of soil can be removed and the lawn can be completely cleared of all root parts.
To prevent the spread of dandelion, do not scarify the lawn. Dandelion seeds can take root particularly well in cracks. Mow the lawn regularly, and when you fertilize, be careful not to overdo the nitrogen. Scatter new lawn seeds in bare areas of the lawn.
Clover is controlled by scarification, herbicide or hedging. Clover cannot grow in low light conditions and dies.
To prevent clover growth, provide the lawn with sufficient nutrition starting in spring and cut regularly but not too short, because clover likes light.