One major factor to always keep in mind when using oleanders is that they have been known to become invasive with their pesky root system. Somehow, the oleander seems to know how to creep into a water line or even worse, a sewer line. Proper planning will solve this issue.

How far do oleander roots spread?

Unidentified toxic roots floating around in the city's water supply aside, plant oleander only where its tough roots can't find a sewer pipe. If your shrub is 8 feet tall and wide, its roots can extend 4 feet beyond its drip line.

Do oleander trees have deep roots?

Oleander bushes form extensive root systems after they have matured and become established. The oleander root system is tough and can grow amongst rocks and other obstacles, making them perfect foundation plants or specimens along the drive.