Is my plant getting too much sun?

Johnsongrass loves full sun, so it is very unlikely that sunlight is causing the yellowing. Focus on water and soil nutrients instead.

Should I cut off the yellow leaves?

Yes, you can trim them off to keep the plant looking tidy. This also helps you monitor if the yellowing is spreading to healthy parts.

Johnsongrass: yellow leaves, causes and fixes

Check these first

Feel the soil to see if it is waterlogged.
Check if the yellowing starts on the bottom leaves.
Look for signs of stunted growth.

Likely causes

Overwatering
Most likely
How to tell: The leaves turn a pale yellow and the soil feels constantly soggy or muddy. You might notice a sour smell coming from the root zone.
What to do: Stop watering immediately and let the top 2 inches of soil dry out. Ensure the planting site has good drainage to prevent water from pooling.
Nitrogen Deficiency
Possible
How to tell: Older leaves turn yellow first while the veins remain green. The plant may also look stunted and stop growing taller.
What to do: Apply a balanced nitrogen rich fertilizer to the soil. Follow the package directions for the correct amount based on the size of your patch.

Yellow leaves on other plants

Find out what's wrong with your johnsongrass

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

It is normal for the very bottom leaves to yellow and drop as the plant grows taller. Worry if the yellowing is moving rapidly up the stem or affecting new growth.

Stopping it coming back

Maintain a consistent watering schedule of every 7 to 14 days and ensure the soil is well draining.

Johnsongrass: yellow leaves? Check yours with a photo

Every plant is a little different. Take a photo of your johnsongrass 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

Is my plant getting too much sun?: Johnsongrass loves full sun, so it is very unlikely that sunlight is causing the yellowing. Focus on water and soil nutrients instead.
Should I cut off the yellow leaves?: Yes, you can trim them off to keep the plant looking tidy. This also helps you monitor if the yellowing is spreading to healthy parts.

Why are my Johnsongrass leaves turning yellow?