Can I save a tree with root rot?

If the rot is caught very early, improving drainage might help, but usually, the damage to the root system is irreversible.

How do I know if my soil is too heavy?

If you dig a hole and it fills with water that takes more than a few hours to drain, your soil is likely too heavy for a Banksia.

Coast Banksia: root rot, causes and fixes

Check these first

Dig down near the base to check for soggy soil.
Gently pull back the soil to inspect the root color.
Check if the tree is planted in heavy clay.

Likely causes

Phytophthora
Most likely
How to tell: The foliage wilts and turns brown or grey, and the roots appear black and mushy rather than firm and white. This usually happens in heavy, waterlogged clay soils.
What to do: Unfortunately, there is no cure for established root rot. Remove the plant and the surrounding soil to prevent it from spreading to other nearby plants.
Overwatering
Possible
How to tell: The soil remains constantly wet and the plant shows signs of stress like drooping or yellowing. This creates the perfect environment for rot to start.
What to do: Adjust your watering schedule to every 7 to 14 days. Always allow the top few inches of soil to dry out completely before you add more water.

Root rot in other plants

Find out what's wrong with your coast banksia

The list above covers the usual causes. Pocket Botanist looks at a photo of your actual plant and tells you the likely cause, how serious it is, and what to try first. Identification and a health check are free.

When to worry

If the foliage is wilting and the roots are black, the plant is likely beyond saving. It is better to remove it to protect your garden.

Stopping it coming back

Ensure your Coast Banksia is planted in fast draining soil and never let it sit in standing water.

Coast Banksia: root rot? Check yours with a photo

Every plant is a little different. Take a photo of your coast banksia and Pocket Botanist tells you which cause is most likely, how serious it is, and what to try first. A few checks a day are free. Save the plant and you get care reminders timed for it.

Get the app · Or check it from a photo now, free

Questions people ask

Can I save a tree with root rot?: If the rot is caught very early, improving drainage might help, but usually, the damage to the root system is irreversible.
How do I know if my soil is too heavy?: If you dig a hole and it fills with water that takes more than a few hours to drain, your soil is likely too heavy for a Banksia.

Guides to these causes

Phytophthora

Is my Coast Banksia suffering from root rot?