Quick Links
Expert supplier Media Clips Info Sheet Expert Advice

Keeping a Healthy Garden near your Septic System

In CategoryTim Whitcombe
ByGardenAdvice Tim Whitcombe

The traditional advice is not to try to grow a garden above septic tanks because of so many things that could go wrong. Like the roots bursting into or clogging the pipes. However, shallow-rooted plants that thrive on nitrogen, such as lettuce, have actually been known to thrive above septic tanks. However, keep in mind that it may or may not be safe for you to eat what grows above your septic system. As long as you’re not in the habit of disposing of harmful chemicals, such as motor oil down your pipes. Nitrogen-feeding plants can live off the waste water that would otherwise mix with groundwater.

Are Weeds and Tall Grass Okay?

If it’s just grasses, weeds, tall brush, and shallow-rooted plants, you’re fine. In fact, they often act as good deterrents to kids and pests. They also act as good deterrents for polluting motorcycles or three-wheeled vehicles. The last thing you want is for anyone to break a bone in your yard or for any damage to be done to your plants, tank, or pipes. In that case, it might be wise to post a sign like “No Trespassing” in that area.


  • Other Things to Avoid Placing Above a Septic System
  • Heavy Equipment. First, it could injure you or someone on your property. Secondly, it could cause the soil to cave in and result in damage to your pipes or septic tank.
  • Most trees or shrubbery. They have lengthy roots. However, there are some that are shallow enough to plant above septic systems listed below.
  • Hard surfaces like concrete or asphalt. You never know what kind of damage it could do to an area as vulnerable as your septic tank. They also don’t absorb the wastewater the way that grass does.
  • Other surface water such as that with comes from roofs, patios and driveways. They can ruin your level sensor for liquids and flood the area and erode the soil above your tank.

Trees and Shrubbery That are Safe Enough Above a Septic System

The following trees and shrubbery have roots that are short enough that they’re safe above a septic system.:


  • Japanese Maple
  • Cherry
  • Dogwood
  • Eastern Redbud
  • Boxwood
  • Azalea


Annuals and perennials also tend to do particularly well above septic systems. This is because they’re typically slow-growing and gentle. Those that are large, fast-growing, and drain water aggressively don’t. Weeping willows, for example, tend to go right after it.

If You are Unsure

Anytime that you have doubts related to gardening above your septic system, you are always welcome to talk to a garden coach. Especially when it comes to something as delicate as your septic system, you want to do everything you can to prevent thousands of dollars in damage. As a result, it is not an area in which you can afford to guess how your plants are going to grow and if they could cause damage. You also can’t afford to just guess whether any food you grow there is safe to eat and you should have your septic system checked before you do.

Leave a Reply

You must be logged in to post a comment.