Oregon may be known as "The Grass Seed Capital of the World," but that doesn't mean keeping a lush, vibrant lawn just happens. Most of our customers ask us for an easy to follow lawn care guide, post new sod installation. With that in mind we've created a detailed lawn care calendar and schedule for the cool season grasses that thrive in our Zone 8b climate.

Want to know when to fertilize and what to use? When to overseed? If you're interested in maintaining a thick, healthy and luscious lawn then this guide is for you. We’ve developed this seasonal lawn care and maintenance schedule for Pacific Northwest homeowners to download and use as a reference calendar to care for their lawns year-round.

Download our Pacific Northwest Lawn Calendar

Lawn Care in the Pacific Northwest

The Pacific Northwest's unique climate offers both challenges and advantages for maintaining a healthy lawn. The area experiences mild, wet winters and dry summers, creating a delicate balance for maintaining a healthy lawn. Excessive rainfall in the winter can lead to waterlogged soil, which can promote moss growth and root rot in grass. Conversely, the dry summers require careful watering practices to prevent drought stress in the grass. Finding the right balance between moisture levels throughout the year can be challenging for lawn care enthusiasts in the Pacific Northwest.

Moreover, the Portland region's dense tree cover and shade can pose challenges for lawn health. Trees can compete with grass for water and nutrients, leading to thinning grass and bare patches. The shade from trees can also inhibit grass growth, making it difficult to maintain a lush lawn. Additionally, the mild temperatures in the Pacific Northwest can create favorable conditions for weed and pest infestations, requiring vigilant weed control and pest management practices. Overall, the unique climate and environmental factors in the Pacific Northwest make lawn care a challenging task that requires careful attention and maintenance.

We encourage our Portland area clients year after year: Whether you're dealing with thinning grass, moss invasion or drought stress, following our seasonal lawn care schedule can help you achieve a vibrant, resilient lawn throughout the year.

Spring Lawn Care

Spring is a crucial time to prepare your lawn for the growing season. Start by aerating the soil to alleviate compaction and promote healthy root growth. Remove any debris, such as leaves and branches, and dethatch the lawn to prevent moss buildup. Overseed bare patches with a suitable grass seed blend for your area to fill in thin areas and improve density. Apply a slow-release fertilizer to provide essential nutrients for growth.

  1. Aeration: Spring is the ideal time to aerate your lawn to alleviate soil compaction and promote healthy root growth. Use a core aerator to pull up plugs of soil, allowing air, water, and nutrients to penetrate the root zone. DO NOT aerate if your lawn still to too wet. It will be more effective to do once it dries out a little bit. (Typically the Months of June and September work well, in the Portland area.)

  2. Dethatching: Remove any accumulated thatch (dead grass and debris) from your lawn to prevent it from suffocating the grass. Use a dethatching rake or a power dethatcher to remove the thatch layer. Optionally, spread a layer of 3 ways blended soil over your lawn to level it out and add some organic nutrients. Overseed with either sun or shade seed depending on your situation. The use a leaf rake or landscape rake to sow the seed into the soil so it helps to stay moist, resulting in better germination.

  3. Overseeding: Overseed your lawn in the spring to fill in bare patches and improve grass density. Choose a grass seed blend that is well-suited to the Pacific Northwest climate for best results. We recommend EMP Seed Sun & Shade Mix 60/40 to use for your overseed application.

  4. Fertilization: Apply a fertilizer product with slow-release Nitrogen. Look for a fertilizer with a balanced N-P-K ratio (nitrogen, phosphorus, and potassium) and apply as per the application rate on the bag. The reason for this is that it will release the Nitrogen slowly over an extended period of time, and you will not need to fertilize your lawn as much. Also, nitrogen is what stimulates the growth of your lawn, it you don't use a slow release (N) product, your lawn will grow like crazy for 2-3 weeks making it so you have to mow more often. Ideally you want to put down 1lb of actual NItrogen per 1000 sqft. We recommend and use Best 22-5-6 X-Cote Turf Gold for this application.

    What is Nitrogen? Nitrogen (N) Nitrogen is the most important nutrient in most fertilization programs. Applied at proper rates, nitrogen stimulates vertical growth, improves turf density, and makes the grass darker green. Every lawn is different, based on the soil type, how much rain and what your taste is for how green you want you lawn to be. Oregon State University's article 'Fertilizing Lawns' is a great reference on this subject and will will help you determine how much (N) you will need to apply per 1000 sqft of lawn.

  5. Weed Control: Spring is also a good time to address weeds before they become a problem. In your planting beds, use a pre-emergent herbicide to prevent weed seeds from germinating, and spot-treat any existing weeds with a post-emergent herbicide. For your lawn, you can use a selective herbicide to treat most broadleaf weeds (this will not kill your lawn, only the weeds). If you have foreign grasses, spray these with a non-selective herbicide (with glyphosate as active ingredient). Once it dies, dig up and remove, add soil and scarify it into the native soil and overseed.

Summer Lawn Care

In the Pacific Northwest, summer can bring dry spells, putting stress on lawns. To keep your grass healthy, water deeply and infrequently to encourage deep root growth. Early morning is the best time to water, reducing evaporation. Raise your lawnmower blades to a higher setting to provide shade for the soil and help retain moisture. Apply a summer fertilizer with a higher potassium content to promote drought tolerance.

  1. Watering: In the dry summer months, it's important to water your lawn deeply and infrequently to encourage deep root growth. Water early in the morning to reduce evaporation, and adjust your watering schedule based on rainfall and temperature.

  2. Mowing: Raise your lawnmower blades to a higher setting in the summer to provide shade for the soil and help retain moisture. Avoid cutting more than one-third of the grass blade length at a time.

  3. Fertilization: Apply a summer fertilizer with a higher potassium content to promote drought tolerance and overall health. Avoid fertilizing during dry periods to prevent burning the grass. If it is hot after you apply the fertilizer, BE SURE TO IRRIGATE YOUR LAWN to wash the fertilize in. Otherwise, you can burn your lawn. We use and recommend Best 16-6-8 Turf Supreme for this application.

  4. Pest Control: Keep an eye out for pests such as grubs, chinch bugs, and army worms, which can damage your lawn. Treat any infestations promptly with an appropriate insecticide.

  5. Disease Prevention: Summer can also bring an increased risk of lawn diseases such as brown patch and dollar spot. Proper watering and mowing practices can help prevent these diseases, but if they occur, treat them with a fungicide as needed.


The unique climate and environmental factors in the Pacific Northwest make lawn care a challenging task that requires careful attention and maintenance.



Fall Lawn Care

Fall is the ideal time to repair any damage and prepare your lawn for winter. Continue mowing as needed and gradually lower the mower blades as the season progresses. Overseed again in the fall to fill in any thin or bare areas, and aerate if necessary. Apply a fall fertilizer with a higher nitrogen content to promote root growth and winter hardiness. Keep the lawn clear of leaves and debris to prevent suffocation and disease.

  1. Mowing: Continue to mow your lawn as needed in the fall, gradually lowering the mower blades as the season progresses. This helps prevent the grass from becoming too long and matting down under leaves and snow.

  2. Aeration: Fall is another good time to aerate your lawn if needed, especially if it experiences heavy foot traffic. Aeration helps improve soil structure and root development. (No need to aerate again if you have done so in the Spring).

  3. Overseeding: Overseed your lawn again in the fall to fill in any thin or bare areas and promote a thick, healthy turf. Choose a grass seed blend that is suitable for fall overseeding in the Pacific Northwest. We recommend EMP Seed Sun & Shade Mix 60/40 to use for your overseed application.

  4. Fertilization: Apply a fall fertilizer with a higher nitrogen content to promote root growth and winter hardiness. Look for a fertilizer specifically formulated for fall application. We use and recommend Best 21-2-4 Nitra King for this application.

  5. Leaf Removal: Keep your lawn clear of leaves and debris throughout the fall to prevent suffocation and disease. Consider mulching leaves with a mulching mower to return nutrients to the soil.

Winter Lawn Care

Winter in the Pacific Northwest is relatively mild, but lawns can still suffer from cold, wet conditions. Avoid walking on frozen grass, as it can damage the blades. Keep the lawn free of debris and clear snow promptly to prevent mold growth. Consider applying a winterizing fertilizer in late fall to strengthen the grass for the cold months ahead. If moss is a recurring issue, apply a moss control treatment in late winter to prevent its spread.

  1. Mowing: As winter approaches, continue to mow your lawn as needed, but raise the mower blades slightly to avoid cutting the grass too short. This helps protect the grass from cold weather damage.

  2. Snow Removal: If your lawn receives snowfall, promptly remove snow from the grass to prevent mold growth and damage to the turf. Use a snow shovel or snow blower to clear the snow, taking care not to damage the grass beneath.

  3. Winterizing Fertilizer: Consider applying a winterizing fertilizer in late fall to help strengthen the grass for the winter months. This type of fertilizer is formulated to promote root growth and overall winter hardiness. You do not want to promote a lot of growth, so use a product that is balanced. This will give you the trace elements that your lawn will build strength from and be healthier in the spring and summer. We use and recommend Best 15-15-15 Triple Pro for this application.

  4. Avoid Walking on Frozen Grass: During periods of freezing temperatures, avoid walking on frozen grass, as it can damage the grass blades and lead to brown patches in the spring.

  5. Moss Control: If moss is a recurring issue in your lawn, apply a moss control treatment in late winter to prevent its spread. Any generic liquid iron concentrate from a big box store will do. Addressing moss early can help maintain a healthy lawn throughout the year.

Download Our Pacific Northwest Lawn Maintenance Schedule

Consistency is key when it comes to lawn care, as regular maintenance helps prevent issues such as weed infestations, pest problems, and disease outbreaks. By following a schedule and staying proactive with your lawn care efforts, you can address potential problems before they become severe and maintain a healthy lawn year-round. Furthermore, using the right products and following a schedule can help you save time and money in the long run by reducing the need for costly repairs and treatments.

Using the right products in conjunction with consistent lawn care schedules for spring, summer, fall and winter are essential steps to achieving a thick, healthy law . By selecting fertilizers,herbicides, and other products and grass types that will thrive in the Pacific Northwest, you can provide your lawn with the nutrients and protection it needs to thrive.

Additionally, following our seasonal lawn care schedule ensures that you address key tasks at the right time, such as aerating, overseeding, and fertilizing, which are crucial for maintaining a lush and vibrant lawn.. For even more information about lawn care in the Pacific Northwest, see Oregon State University's guide: Practical Lawn Care for Western Oregon.

Proper lawn care in the Portland area requires attention to our region's unique climate and conditions. By following a seasonal lawn care schedule and addressing specific challenges like moss and drought, you can maintain a lush, healthy lawn year-round. With the right care, your lawn can be a beautiful and resilient part of your landscape, enhancing the beauty of your outdoor space.

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