Washington Revised Code Title 15. Agriculture and Marketing § 15.54.500. Turf fertilizer--Prohibitions on application, sales, and retail display

(a) Except as otherwise provided in this section, apply turf fertilizer that is labeled as containing phosphorus to turf;

(b) Apply turf fertilizer labeled as containing phosphorus to turf when the ground is frozen;

(c) Intentionally apply turf fertilizer labeled as containing phosphorus to an impervious surface;

(d) Except as otherwise provided in this section, sell turf fertilizer that is labeled as containing phosphorus; or

(e) Display turf fertilizer that is labeled as containing phosphorus in a retail store unless the turf fertilizer is also clearly labeled for a use permitted by this section.

(a) Application for the purpose of establishing grass or repairing damaged grass, using either seeds or sod, during the growing season in which the grass is established;

(b) Application to an area if the soil in the area is deficient in plant available phosphorus, as shown by a soil test performed no more than thirty-six months before the application; or

(c) Application to pasture, interior house plants, flower and vegetable gardens located on either public or private property, land used to grow grass for sod, or any land used for agricultural or silvicultural production.

(4)(a) Nothing in this section:

(b) A city or county may not adopt a local ordinance regarding the application or sale of turf fertilizer that is labeled as containing phosphorus that is less restrictive than this section.