What Plants Are Safe to Grow Over Septic Tanks and Drain Fields
Your Best Choices and a List of What to Avoid Planting
Certain trees and shrubs can cause damage in around septic tanks and drain fields with their aggressive roots. Which plants were the worst to grow over a septic system and which are safer choices?
Plants Safe to Grow Over Septic Tanks and Drain Fields
Do not become so paranoid over the potential of damage to septic systems caused by roots that you abstain from planting these areas altogether. Growing the right kind of vegetation here is not only permissible but actually advisable.
Plants will prevent erosion and suck up some of the excess moisture from the drain field.
Perennials, annuals, small, non-woody ground covers, and grasses (including ornamental grasses) work best around your septic tank and drain field because their shallow root systems are less likely to invade the underground system and cause it damage. There are, of course, innumerable examples of such plants, so you will want to narrow down your choices. A good way to start is to consider growing conditions:
- If the area is sunny, consider these ten best perennials for sunlit areas.
- But if the spot does not get much sun, you will probably be happier with these shade-garden plants.
- The soil around septic tank drain fields is sometimes wetter than average, sometimes saltier than average — and sometimes both. Cover both bases with perennials such as bee balm, hollyhocks, and wild violets, which tolerate both wet ground and salt.
- Bambi will not turn his nose up at plants growing over septic systems, so if you have a problem in your region with this big pest eating your plants, you will want to look into deer-resistant perennials and deer resistant ground covers, as well as spring bulbs and ornamental grasses that deer do not eat.
It is not safe to grow (and eat) food crops in the ground around a drain field because eating them might entail ingesting harmful bacteria.
If you must grow trees and shrubs, shallow-rooted kinds are better to grow around septic tank drain fields. Shallow-rooted trees and shrubs include:
- Dogwood trees
- Japanese maple trees
- Eastern redbud trees
- Cherry trees
- Azalea shrubs
- Boxwood shrubs
- Holly shrubs
The Worst Plants to Grow Over Septic Systems
Generally, avoid planting large, fast-growing trees. But, in addition, some of the worst offenders are trees and shrubs with root systems that aggressively seek out sources of water. They are not fussy about the water source they tap into, meaning the pipes in your septic tank drain field are very much fair game. Weeping willow trees are a notorious example. There are many trees and shrubs to avoid, but here is a small sampling:
- Pussy willow shrubs
- Japanese willow shrubs
- Aspen trees
- Lombardy poplar trees
- Birch trees
- Beech trees
- Elm trees
- Most maple trees other than the Japanese
- American sweetgum trees
- Ash trees
- Tulip trees
Let’s say you have avoided growing any of the most problematic plants directly over your septic tank drain field. Are you out of the woods? No! There is still a danger posed by any large, mature trees that may be growing anywhere near your septic system.
The general rule is that such a tree needs to be as many feet away from your septic drain field as it is tall — and that is a minimum requirement. So a specimen 50 feet tall at maturity should stand at least 50 feet away. Failing that, it is possible to install root barriers to try to keep tree roots from invading your septic drain field (similar to the bamboo barriers used in controlling invasive bamboo).
Why You Have to Be So Careful Planting Over Septic Tank Drainfields
It is primarily the drain field pipes that you have to worry about when planting around septic tanks. You do not want roots penetrating the perforations and gumming up the works. All of the parts of this carefully tuned system must be functioning properly, else the result is a mess — and a costly one, at that.
While annual flowers are sufficiently shallow-rooted to serve as plants for septic fields, what makes them less than ideal is that they have to be planted every year. The less gardening work you have to do in a septic tank area, the better (both for you and for the septic system). Always wear gloves when digging in a drain field to protect yourself. Never dig deeply (you could damage the system).
Read the full article here: The Best and Worst Plants to Grow Over Septic Systems http://bit.ly/2xzOmB3