6 Acceptable Plants to Cover a Septic Tank Drain Field

A septic tank drain field can be tough to cover with any type of plants and flowers. You must take care not to plant anything on or near the mound that has roots that will grow down into your septic system and cause damage. You can, however, cover the field if you use acceptable plants and flowers. Here are 6 suggestions that you can choose from. Feel free to mix these plants to your liking.

Lawn Grass

Lawn grasses have a very short root systems and are a good choice for covering a septic tank drain field. Popular grasses for this project include Kentucky bluegrass and Rye grass. It will have to be regularly mowed to keep the weeds from growing. Mowing also helps keep down rodent infestation.


Perennial flowers such as day lilies or poppies can be successful planted on your septic tank field. You will need to put down topsoil of approximately 6 inches before planting. Also, you will need to add mulch around the flowers to be sure the soil is not exposed. Planting the flowers close together will help not have to use very much mulch. Keep in mind that you may have to access the septic tank at some point, so you may want to plant your valuable flowers in another area, so you do not lose them.

Wild Flowers

Wild flowers also have a short root system and can bring a splash of color to the area if it is in a prominent part of your yard. You can purchase a variety of wild flowers online or at a home improvement store, or garden center. They usually come in seed packets. You will be able to choose a mixture of colors to match your taste. They are easy to grow and there is little maintenance. Do put down an inch or so of topsoil to assure that your seeds sprout.

Septic Tank Mix

Septic tank mix, also known as prairie mix, is a mixture of native wildflowers and grasses. It is easy to plant from seed, and you will not need to use topsoil for this covering. It is highly recommended for this purpose because it takes in the excess water from the mound and the root systems in this mixture are very short. You will find this mixture at any store that sells flowers. It is easy to grow and literally no maintenance.

Ornamental Grasses

Ornamental grasses are easy to grow. Because they also grow out a little and spread but do not grow deep. Their root systems are acceptable for a septic tank drain field. Its easiest to buy a small container of ornamental grass from your garden center and plant it directly into the ground. There are several varieties and colors to choose from. After planting, they are very low maintenance. Another perk is that they drop seeds and feed the birds.

Container Garden

You can make your septic tank easily accessible by placing a container garden on your mound. Cover the area with pea gravel. Plant flowers and grasses in containers and place on the gravel. Be sure that you do not plant fruits or vegetables in these containers though. Fruits and vegetables cannot be consumed if planted on a drain field because they will be contaminated. Instead, choose a combination of the above to give your septic area color and depth.