Can I save a leaf that has spots?

It is best to remove spotted leaves to stop the fungus from moving to healthy parts of the plant. The plant grows fast enough that it will replace the foliage quickly.

Will these spots kill my castor bean?

Usually no, but they can weaken the plant if left untreated. If the infection reaches the main stem, it can cause more serious damage.

Castor bean: spots, causes and fixes

Check these first

Inspect the undersides of the leaves for fuzzy growth or discoloration.
Check if your plant is crowded by other vegetation.
Feel the soil to see if it stays soggy for more than a few days.

Likely causes

Fungal leaf spot
Most likely
How to tell: You will see dark, circular spots that might have a yellow halo around them. These often appear after periods of heavy rain or high humidity.
What to do: Remove the affected leaves immediately to prevent spores from spreading. Avoid overhead watering to keep the foliage dry, and ensure the plant has plenty of space for airflow.
Bacterial blight
Possible
How to tell: These spots look water soaked and can turn brown or black quickly. They often appear on the lower leaves first where humidity is trapped.
What to do: Prune away infected stems using sterilized shears. Apply a copper based fungicide if the infection continues to spread across the plant.

Leaf spots on other plants

Find out what's wrong with your castor bean

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

Worry if the spots are spreading rapidly to the main stems or if the plant begins to lose leaves quickly. A few small spots on older leaves are usually harmless.

Stopping it coming back

Water only at the base of the plant to keep the leaves dry. Space your plants at least 3 to 5 feet apart to encourage good air movement.

Castor bean: spots? Check yours with a photo

Every plant is a little different. Take a photo of your castor bean 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 leaf that has spots?: It is best to remove spotted leaves to stop the fungus from moving to healthy parts of the plant. The plant grows fast enough that it will replace the foliage quickly.
Will these spots kill my castor bean?: Usually no, but they can weaken the plant if left untreated. If the infection reaches the main stem, it can cause more serious damage.

Guides to these causes

Leaf Spot

Why are there spots on my castor bean leaves?

Check these first

Not sure what's wrong with your castor bean?