What plants can I grow in the septic field?
Tips and tricks of what to plant over an absorption trench
If you have a green thumb, you might be wondering if you could grow a garden around your septic system. They pose a challenging problem - not everything is suitable to be grown on the drain fields. You also need to be careful as the system can also collapse due to heavy tilling and deep-rooted plants.
Some plants do better than others in this environment while some water-loving plants, trees, and shrubs can quickly overgrow and invade the pipes and collapse the septic system if care is not taken. It is okay to grow plants or a garden if it is done with caution. Shallow-rooted plants and grass are the usual choices and even groundcovers and climbers can be safely planted. Trees, fruits, and vegetables should not be planted over or around the leach field. Also, avoid placing raised garden beds over the absorption trench as it can hinder the evaporation process and decrease the efficiency of your septic system.
Overview of Septic Systems
Septic systems are common in rural areas where the council sewer lines are not available.
Septic systems consist of a septic tank and leach field. The wastewater flows from the home to the septic tank where the organic matter is broken down. It is separated into different layers, i.e. sludge, scum, and effluent. The effluent (the liquid waste) is discharged into the leach field wherein the soil absorbs the harmful nutrients and purifies the water before it reaches the water table.
What plants can be grown over a leach field or absorption trench system?
A septic tank is usually installed at a depth of 1m underground so you do not want the roots of your plants to extend too deep.
The best options are flowers, hedges and grasses that do not have deep roots and will not extend deep enough to affect the pipes or the septic tank. These assist in the effective functioning of absorption trenches and purify the effluent before it enters the environment.
Grass can be grown very effectively directly over the leach field.
Shallow-rooted plants, climbers, and shrubs can be grown in the surrounding areas but not directly over an absorption trench. Fast-growing trees like cedar and weeping willows should be strictly avoided. Fruits and vegetables should not be planted over the absorption field as eating them could put you at risk of bacterial contamination.
Tips for choosing the right plants for around your home wastewater treatment system
- Shallow-rooted plants and grass are your best friends when it comes to septic systems
- Plants that thrive on less water or are drought-friendly are the best
- Choose plants that can thrive in a salty environment
Factors that influence the vegetation around your septic system
- Soil quality
- Nutrient levels
- Drainage
- pH level
- Effluent quality
- Climate conditions
- Soil sensitivity of plants
Detergents, fabric softeners, and household effluent can increase the level of salt in the soil in the absorption area. Before planting check the pH level of the soil and if the soil is alkaline, it may be better to use plants that can tolerate high salt levels.
Avoid planting trees near your septic system
Trees are a strict no for planting around a septic system. The strong roots can extend deep enough in the search of moisture and nutrients and can quickly invade and block the pipes.
Trees and even shrubs are not recommended to be planted over septic systems. In case you want to grow trees or shrubs, plant them far away from the septic system so the roots do not reach the unit or drain.
Plants safe for Septic Systems
This list is not comprehensive and you should check with your local nursery before you finalise the plants you grow on or around the septic system.
Grass
- Sedge
- Lawn turf grass
- Weeping grass
Groundcovers
- Oyster plant
- Royal mantle
- Blue star creeper
- Lily Turf
- Native violet
- Perennial Aster
Climbers
- Bougainvillea
- Snake Vine
- Jasmine
- Happy wanderer
- Glory Vine
- Japanese Honeysuckle
Shrubs
- Swamp Hibiscus
- Jasmine
- Tea-tree
- Oleander
- Abelia
- Papyrus
Our expert septic management advice
- Do not grow vegetables, fruits, shrubs and trees near your septic system.
- Having plants or grass over the leach field holds the soil in place and assists in the absorption of nutrients, preventing soil erosion and ensuring the proper functioning of the septic system.
- Do not add additional soil over the drain field.
- Wear gloves whenever you are working in the garden over or around the drain field.
- Growing plants also promote oxygen exchange and encourage the necessary soil moisture removal through transpiration.
- If you can observe water pooling in your drain field or if water backs up into your home, contact your local wastewater & septic specialist for immediate assistance. Your drain field could have failed and would need an inspection and repairs.
- Do not go overboard with tilling the soil when planting as it may damage the pipes
Your Local Septic System Professionals
Are you looking for specialist septic advice in South-East Queensland regions such as; the Gold Coast, Brisbane, the Sunshine Coast or Logan? Express Wastewater Solutions are industry professionals when it comes to completing professional septic system installations, repairs and maintenance.
To find out more about septic systems and the plants safe to be grown over the leach field, give us a call at 1300 722 517 or complete our quote request form.