Bring your lawn to life with septic-approved landscaping
Septic systems don’t add much aesthetic appeal to your home, but with the right landscaping, you can spruce up your yard and fill the space near your septic tank and drain field. However, not all flora play nicely with septic systems—so what can you put on top of a septic field?
Below, we’ll walk through some of the best septic tank landscaping ideas so you can cultivate a beautiful, blossoming garden that hides the not-so-nice-looking parts of your yard.
As you mull over your septic tank landscaping options, you'll want to seek out plants with shallow root systems. Otherwise, if the roots are too long, they could block your pipes or penetrate your septic tank, leading to poor drainage or sewage seeping into your yard.
Some of the best shallow-rooted plant options are:
Grass, including ornamental and perennial grasses. Examples include blue fescue (Festuca glauca), purple fountain grass (Pennisetum setaceum ‘Rubrum’), and maiden hair grass (Miscanthus sinensis).
Aesthetically pleasing (and durable) perennials, such as foxglove (Digitalis spp.), cardinal flower (Lobelia cardinalis), yarrow (Achillea millefolium), and ornamental onions (Allium spp.).
Low-growing, non-woody ground covers. If your yard is sunny, explore options like bugleweed (Ajuga), ground ivy (Glechoma), or periwinkle (Vinca).
You’ll also want to think about how much sunshine your property receives before making any landscaping decisions. If it doesn’t get much, look for plants that grow well in the shade, such as:
Ground covers, such as ferns, mosses, or wintergreen (Gaultheria). Spotted dead nettle (Lamium maculatum), sweet woodruff (Galium odoratum), and creeping phlox (Phlox subulata) are also worth considering.
Ornamental plants, like bleeding heart (Dicentra spp.), lilyturf (Liriope spp.), and coral bells (Heuchera sp.).
Your septic tank shouldn’t stink, but occasionally, you might notice the occasional scent of sewage coming from your yard. To help the area smell (and look) better, you can invest in pleasant-smelling plants, including:
Ground covers with aromatic foliage, like creeping rosemary (Rosemary officinalis horizontali) and creeping thyme (Thymus spp.).
Fragrant, flowering perennials like lavender (Lavendula angustifolia or L. intermedia), white sage (Salvia apiana), and Asiatic lilies (Lilium asiatica).
Scented flowering vines like honeysuckle (Lonicera sp.) and jasmine (Jasminum sp.).
Generally speaking, it’s not a good idea to plant shrubs or trees on top of your septic system since they have extensive roots that can damage your tank or drain field. However, if you have your heart set on it, you can consider one of these smaller, shorter-rooted ornamentals:
Easy-to-maintain dwarf versions of colorful trees, including azaleas (for example, the Rhododendron ‘Robleza’) or Japanese maples (such as the Acer japonicum ‘Fairy Lights’).
Small shrubs, such as the true dwarf English boxwood (Buxus sempervirens suffruticosa).
Dwarf varieties of weeping trees, including the weeping blue atlas cedar (Cedrus atlantica ‘Glauca Pendula’) and the ‘Covey’ eastern redbud (Cercis canadensis ‘Covey’).
Your drain field and other septic areas tend to collect more water than other parts of your lawn, so you’ll want to aim for plants that can handle ongoing moisture. Be careful, though: Extra-thirsty plants like willows (Salix) can put deep roots into the soil, so buy ones with shallow roots. Good options include:
Toad lily (Tricyrtis)
Stream orchid (Epipactis gigantea)
Bearded iris (Iris germanica)
As we’ve covered, any plants with deep or aggressive root systems are a no-go for septic tank landscaping. You should also avoid tall or fast-growing plants. Here are a few specific plants that shouldn’t go over your septic tank:
Bamboo
Blackberry or raspberry bushes
Most trees, including water-loving ones like birch and elms
Similarly, fruit, vegetables, herbs, and other edible plants don’t belong in your septic area—unless you’re using them for decorative purposes. You shouldn’t eat them because they could contain bacteria from your septic system, making you sick.
Besides knowing what you can (and can’t) plant near your tank, there are a few other septic landscaping tips to remember. Here are some of the most important.
Shallow-rooted plants lose moisture quicker than deep-rooted ones, so you might want to mulch over your septic system to provide extra support. However, you don’t need to lay as much mulch as you would with a garden bed.
Weight can damage the underground pipes in your drain field, so you should avoid placing heavy objects (like large planters, boulders, and pavers) on top of it. Building decks, sheds, or other structures isn’t a good idea.
Although septic tank lids aren’t exactly nice to look at, you shouldn’t bury yours in case your local septic tank pro needs to access it. If you want to hide it, you can cover it up with a faux rock, planter, or wooden box.
We’ve explained how deep-rooted plants can damage a septic tank from the outside, but plenty of things can ruin it from the inside, too. For example, flushing bulky items (like paper towels, diapers, and wipes) can clog your septic tank. Cooking oil, grease, and household chemicals can also harm your system. And since a new septic system costs between $3,460 and $11,450, it’s worth following these guidelines.
Talking with a septic pro before planting trees near your tank is best to ensure the roots won’t interfere with your septic system. However, there is an easy way to figure out where to plant a tree—but you’ll need to know how tall it can get when it’s fully grown. For instance, if the tree can reach 50 feet, plant it at least 50 feet from your septic system.
There’s no standard septic tank depth, but in most cases, they sit between 4 inches and 4 feet below the ground. When determining where to bury a tank in your yard, your septic professional will consider the natural landscape of your property and the depth of your main sewer line. It’s difficult for grass or plants to grow when your tank is near the earth’s surface, so if you want to plant anything over it, the pro will probably recommend putting it at least 4 inches to 6 inches deep.
On average, septic tanks last between 20 and 40 years. However, this time frame may vary depending on a few factors, including the tank’s material and the soil type. You can extend the life of your tank by scheduling a septic tank pumping every three to five years and being mindful about what you put down your drains and toilets. In short, human waste and toilet paper are the only things that should go into your septic tank.
To keep roots from growing into a septic tank. However, there are other steps you can take if existing tree roots are getting close to your septic tank. For one, you can install root barriers, which physically block roots from reaching your septic tank. You can also use chemical solutions in your yard or plumbing system to deter root growth.
