Should I cut off all the spotted leaves?

Yes, removing infected leaves helps prevent the fungus from spreading to healthy parts of the plant. Just make sure to clean your shears with alcohol between cuts.

Can I save a plant with heavy spotting?

If the spots cover most of the foliage, the plant may struggle to produce energy. It is often better to remove the plant to protect your other gladiolus.

Sword Lily: spots, causes and fixes

Check these first

Inspect the undersides of leaves for tiny insects.
Check if the foliage stays wet for long periods.
Look for signs of decay at the base of the plant.

Likely causes

Fungal Leaf Spot
Possible
How to tell: You will see small brown or reddish spots that may have a yellow halo around them. These often appear after periods of heavy rain or overhead watering.
What to do: Remove and destroy any heavily infected leaves to stop the spread. Water only at the base of the plant to keep the foliage dry.
Thrips
Possible
How to tell: These tiny insects cause silvery or white streaking and irregular spots on the leaves and flowers. You might see the insects themselves if you shake a flower spike over a white piece of paper.
What to do: Apply neem oil or insecticidal soap to the foliage every 7 days. Ensure you cover both the top and bottom of the leaves thoroughly.

Find out what's wrong with your sword lily

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 across the entire plant or if the flower spikes are becoming deformed. A few small spots on older leaves are usually harmless.

Stopping it coming back

Provide plenty of space between plants to improve airflow and always water at the soil level rather than over the leaves.

Keep your sword lily healthy from here

Save your plant in Pocket Botanist and you get care reminders timed for this plant, plus a care history that shows what worked. Identification and a health check are free.

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Questions people ask

Should I cut off all the spotted leaves?: Yes, removing infected leaves helps prevent the fungus from spreading to healthy parts of the plant. Just make sure to clean your shears with alcohol between cuts.
Can I save a plant with heavy spotting?: If the spots cover most of the foliage, the plant may struggle to produce energy. It is often better to remove the plant to protect your other gladiolus.

Why does my gladiolus have spots on its leaves?