In most of western Oregon, moderate temperatures allow for year-round turf growth. Thus, lawn care is important all year long. Keep in mind that timing is everything. Performing critical maintenance tasks at the wrong time generally yields poor results.
In some areas, Oregon lawns need little or no fertilizer to grow other than to replace nitrogen. Oregon has specific geologic areas concerning the soil. Each area requires different fertilization techniques depending on the regional soil makeup. A soil test is recommended to fully understand your particular regional soil composition..
COASTAL OREGON: Here soils range from fine sand to clay with a pH range of 5.5. Phosphorus levels might be low, but potassium are typically medium to high. These soils might benefit from a lime application. Bentgrasses are suitable for this area.
SOUTHWESTERN OREGON: Soils here include decomposed granite to black clay. Soil pH is in the low 6 with phosphorus and potassium at medium levels. Decomposed granite is infertile and requires complete fertilizers.
CENTRAL / EASTERN OREGON: Soils often are a sandy loam to silt . Phosphorus levels are normal, but potassium is usually high in this area. Calcium and magnesium are plentiful. Check the soil pH level. Some areas here may require additional iron.
WILLAMETTE VALLEY: Mostly clay with balanced pH levels with adequate phosphorus, potassium, calcium and magnesium.
Oregon Insect Problems: European crane fly larvae that eat grass roots in late winter are the only real problem in western Oregon. Water infrequently in late summer and make sure that the upper 2" of soil dries out completely between watering's; or stop irrigation altogether, especially if crane fly adults are seen on the lawn.
Other insect problems:
Lawn diseases found on Oregon lawns
Promoting healthy growth and avoiding conditions that cause stress to your turfgrass is the best way to prevent a severe disease outbreak. Stressed lawns are an open invitation for a lawn disease to gain a foothold. Optimal maintenance practices are the best way of avoiding stressed turfgrass.
Even if a pathogen is present in the soil, infection will not occur unless the environmental conditions are conducive to disease development. Once turf diseases have become active, they can cause heavy damage if not treated properly. Here is a list of common diseases to Oregon lawns:
Professional lawn care associations: Northwest Turfgrass Association