Don’s Expert Answers: Invasive roots query

Question From:
Elisa in Henley Beach South , Adelaide South Australia

Nature of problem:
Invasive roots query

Type of Plant (if known):

Symptoms of Plant Illness (please try NOT to diagnose your problems yourself):
No illness

Soil Type (e.g. sandy, clay or loam) OR Potting Mix Type:

How often do you water the plant:
Every 3 to 4 days

How many hours of sunlight does the plant get each day:
Full day

How long since you planted it:
2 years

Have you fertilised? If so, with what and when:
Yes, very 6 months. Product name not know as hubby has put it somewhere I can’t find!!

Is the plant indoors or outdoors:

Is the plant in a pot or in the ground:

What other treatments have you given the plant:

Upload photo if available:

Other Comments:
My neighbour heard on the ABC radio gardening segment recently that the roots from the bougainvillea plant are quite invasive. He is now concerned that the plant, which sits on my property on our shared fence line, will damage his clay pipes.
I have been researching information on the roots of the Bougainvillea and require further confirmation.
I have read that the plant does not like a lot of water and if pruned regularly and kept under control the roots will not become invasive. In regard to the watering we have an irrigation system in which the garden is watered every 3 to 4 days and I do prune it regularly. Am I correct to assume that my plants roots would not be invasive as they are not trying to source an alternative water source?

Hi Elisa, In general bougainvillea roots are not prone to growing into water pipes, but their tops are very invasive and can grow over trees and kill them. Your problem is that IF your neighbour has clay pipes, they usually leak over time and attract nearby plant roots. As the rigid clay pipes settle over time, the joints open up & leak and eventually the roots may grow inside. This doesn’t often happen with plastic pipes. In South Australia, the harsh climate often forces plants’ roots to go looking for ever more water. Don