Tacoma Hydroseeding offers professional hydroseeding and Erosion control services in Tacoma WA and surrounding areas at an affordable price. Call 253-397-3655 for instant quote. Guaranteed results. Hydroseeding is fast becoming the preferred method for residential lawns, erosion control and re-vegetative ground coverage in Washington State. It is a process where seed, water, fertilizer, mulch, and a holding agent (tackifier) are mixed together and applied through a specialized machine called a hydroseeder or sometimes referred to as a hydromulcher.