Perennial Plants for a Septic System

Kinnikinnick

• Arctostaphylos uva-ursi, also commonly known as kinnickinnick, is a hardy groundcover plant native to the northwestern United States that features shallow, spreading roots that will not damage a septic system. It will spread to cover a septic tank field in a few years and resists damage from being walked on or disturbed to repair the septic system. Partial shade is its preferred lighting condition, and it requires little water. Kinnikinnick is more frost- and cold-hardy than other perennials, but it may not thrive in hot Southern climates.

Goldenrod

• Bright yellow plumes of goldenrod flowers will camouflage your septic mound without damaging it. Solidago nemoralis, or old field goldenrod, and Solidago speciosa, or showy goldenrod, both do well in full to partial sun. Plants that have low watering requirements are generally recommended for use on a septic field because irrigation or regular watering will shift the soil around the septic tank, causing damage. Root systems on water-loving plants may also pull up and hold too much moisture from the septic system, leading to high bacteria levels in the soil. Goldenrod grows well across the United States, but some varieties are more cold-hardy than others.

Troublesome Sedge

• Despite its name, Carex molesta is a good choice for planting over septic drain lines or a septic tank field. Plants that need regular dividing can cause compaction of the soil around the lines, clogging them. Troublesome sedge will spread its bushy, 3-foot-tall clumps of sedge grass across any open area with full sun. Other sedges and wildflowers can be combined with troublesome sedge for a natural meadow-style garden over your septic system without requiring extra watering or special care. Troublesome sedge tolerates a variety of climates but may die back during harsh winters.

Fescue

• Any shallow-rooted, hardy grass works for covering septic systems. Fescue grass varieties like Festuca longifolia and Festuca rubrum work especially well because of their drought, shade and frost tolerances. Slow growing reduces the need for mowing to once or twice a year, limiting the amount of traffic over the septic system. Walking around on the septic mound will compact the soil and slow the decomposition process. Fescue varieties can be combined to create an attractive disguise for a septic tank mound that increases aeration and evaporation in the soil.