Aftercare For Your Newly Hydroseeded Lawn

Your newly hydroseeded lawn has all the requirements for a healthy start – a blend of premium certified grass seed, a quality starter fertilizer, and a protective layer of mulch to conserve moisture. Your goal now is to provide the grass seed with a continuous supply of moisture. Here’s how to prep your lawn for hydroseeding! Too much or too little water will cause the grass seedlings to develop a weak root system, causing slow establishment and sparse growth. Germination time depends on the weather, temperature, and AMOUNT OF WATERING BY THE OWNER. Usually, the grass is visible in 7 days – a few days longer if temperature is below 60 degrees. The performance of your yard depends on a few days of special care. To assure maximum performance, WATERING IS ESSENTIAL. The care your lawn receives in watering, fertilizing and mowing will determine its success. When the grass starts to appear, keep in mind what you see is about 50% of the initial seed germination. The remainder will follow and continue to thicken into sod within the next 2 to 3 weeks. At first, you may think some areas were missed, but that is not the case. Germination time differs with each type of seed.


Newly hydroseeded lawns require LESS water more often and growing hydroseeded lawns require MORE water less often. During the first two weeks, keep the top layer of soil and mulch damp or else the seedlings will dry out and fail to take root. Light, frequent waterings will maintain proper moisture without flooding or washing away the seed.

  • Water once a day, early morning, in normal northwest weather. HOWEVER, IF WEATHER IS WARM AND DRY, IT MAY BE NECESSARY TO WATER 2 OR 3 TIMES A DAY. Reduce or discontinue watering during wet or cool periods. Remember that wind alone will cause the soil and seedlings to dry out.
  • During the initial watering period, the lawn may be walked on, but avoid dragging any hose, sprinkler, etc. across the lawn. This may cause damage to the new seedlings.
  • An established lawn (after the first few mowings), requires 1 to 1.5 inches of water every week.


Mowing will stimulate growth and thickness. Start mowing your new lawn as soon as possible, usually in 3 weeks during summer months, when it reaches a height of 2.5 to 3 inches. Mow to a height of 2 inches for the first mowing. Be careful when mowing your newly seeded lawn. Avoid dragging or twisting the mower and engage drive wheels slowly. This will help eliminate any uprooting or gouging of the lawn surface.

  • Frequent mowings will stimulate growth and thickness and cause your lawn to fill in more rapidly.
  • Never cut off more than one-third the height of existing grass blades.
  • Always keep your mower sharp. Dull blades can damage your grass.
  • On new lawns, run rotary mowers at lower speeds to avoid seedlings and mulch from being sucked up into the mower.
  • Mow an established lawn to a height of 2 to 2.5 inches. This will ensure that you will not cut the grass below the collar of the blades.
  • The difference between the temperature of the air at the tip of the blade and the base of the shaft at ground level can have a range of 35 degrees. In other words, on a day with the air temperature being 100 degrees, the ground-level temperature will be approximately 65 degrees. In essence, the lawn requires less water because the grass provides its own shade. Do not cut away the shade.


Your lawn should be fertilized about 30 days after being hydroseeded and again in another 30 to 45 days. Apply fertilizer when the lawn is dry and then water thoroughly. Use a balanced fertilizer such as 16-16-16 or a starter fertilizer, following label instructions carefully.

  • Always use a quality fertilizer with a slow-release formula.
  • Always follow label instructions, applying fertilizer at recommended rates.
  • Do not use a weed killer on your new lawn. Wait for 3 to 4 months to use weed killers and follow label instructions for new lawns carefully.
  • Once your lawn is established, fertilize it in the spring, summer, and fall.

Should portions of your yard washout due to heavy rains or for some other reason, in certain areas, fail to perform to our standards, we will analyze the problem and re-spray, if necessary, at no charge to you. Our hydroseeded lawns are guaranteed. If you have any questions or feel you need assistance, please call Pacific Northwest Hydroseeding, LLC!

We Also Provide High-Quality Hydroseeding Services in:

Bonney Lake | Eatonville | Puyallup | Sumner | Tacoma | Auburn