Preparing for Hydroseeding
The quality of your finished lawn depends upon preparation before hydroseeding, as well as regular care after hydroseeding.
Key factors in soil preparation include:
- removal of rocks and debris
- control of existing weeds
- addition of topsoil or the modification of existing soil
- adjustment of soil acidity
- surface contouring and smoothing
You can grow grass by seeding directly on the existing native soil but because the soil in Kitsap and Pierce counties almost always has a high content of sand and gravel, it doesn’t hold water or nutrients very well. The result is usually a lawn that will not stay green especially in the hot months of summer and has a higher than normal amount of moss and weeds.
Topsoil Preparation
The best way to prepare a lawn is to spread topsoil mix over the entire area to be planted. Since our local soils usually have a lot of rocks, it is not recommended to blend the topsoil in with the existing soil. The preferred method is to grade the existing soil, kill all weeds and grasses, spread approximately 3-4 inches of topsoil mix then rake it smooth, roll it lightly, rake it again to level any high or low areas and do a final rolling to lightly compact the topsoil. Now it’s ready to be hydroseeded.
Existing Soil Preparation
If you don’t intend to add topsoil, the soil surface should be loosened, preferably to a depth of at least four inches to ensure that the new grass plants can establish deep roots.
Rocks larger than about one inch should be removed. A rule of thumb is to remove anything larger than you wish your lawn mower to hit, or that you would feel comfortable contacting if you fell.
Recent construction sites may also require clearing of protruding tree roots, steel banding, concrete, and lumber ends. Then it’s time for raking and rolling again. With this method it’s even more important to kill all existing weeds and grasses prior to hydroseeding.
Weed Control
Existing weeds and grasses should be eliminated with a herbicide such as “Roundup” prior to planting. Usually the herbicide will become inactive 7 days after application and the treated soil can then be hydroseeded. Follow herbicide label directions to ensure the product will not affect the new seed.
Sprinkler Systems
The addition of a sprinkler system will aid greatly in establishing and maintaining your new lawn. If a sprinkler system is to be installed, it should be installed just prior to hydroseeding the lawn.
Shortcuts in soil preparation often lead to problem areas, susceptibility to fungus and insect infestations, and inability to withstand unusual watering schedules. Adequate planning and preparation can save you headaches and money in both the long and short term and help assure you will end up with a beautiful new lawn that you and your family can enjoy for years to come.