Tri-Cities Lawn Care Calendar

Dethatching

Thatch builds up fast in Eastern Washington because of irrigation and our dense soils. Dethatching is usually done from mid-spring into early fall.

• Spring (April–June): clears out winter buildup and prepares the lawn for summer.
  
  
• Late Summer/Fall (August–October): gives the lawn a clean surface before overseeding or fertilizing.
  
  
• It’s best to avoid dethatching in the peak of summer unless the lawn is well-irrigated.
  
  

Overseeding

Overseeding works best when paired with aeration. Our climate gives you two good windows:

• Late April–June
  
  
• September–mid-October
  Spring fills in winter damage, while fall gives seedlings time to settle in before the cold. Overseeding in July or August isn’t ideal unless you can keep the soil consistently moist.
  
  

Soil Conditioning (Lime / pH Adjustments)

Eastern Washington soils often drift acidic due to irrigation and clay content. If your lawn struggles to stay green even with regular fertilizer, your pH may need adjusting.

• Best applied right after aeration, anytime April through October, when water can help pull the material into the soil.
  
  

Why This Schedule Works Here

Tri-Cities lawns face intense summer heat, compact soils, and long dry spells. By handling major lawn work in the months where conditions are mild, you help the lawn build stronger roots and stay greener through the year. Aeration, dethatching, and overseeding all work better when the grass is actively growing—and that’s why timing matters.

Need Help With Your Lawn?

If you’re in Kennewick, Pasco, Richland, or anywhere nearby, we can take care of the aeration, dethatching, overseeding, or soil-conditioning for you. Just reach out whenever you’re ready.