Can I save a yellow leaf?

No, a yellow leaf will not turn green again. It is best to snip it off so the plant can focus its energy on new growth.

Does too much sun cause yellowing?

Usually no, as this plant loves full sun. If it is yellowing in direct sun, it is likely a watering issue rather than a light issue.

Prostrate knotweed: yellow leaves, causes and fixes

Check these first

Feel the soil to see if it is soggy.
Check the drainage holes for blockages.
Inspect the roots for any signs of decay.

Likely causes

Overwatering
Possible
How to tell: The leaves turn yellow and feel soft or mushy to the touch. You might also notice the soil stays damp for more than two weeks.
What to do: Stop watering immediately and let the top 2 inches of soil dry out completely. Ensure your pot has drainage holes so excess water can escape.
Nutrient deficiency
Possible
How to tell: The older leaves turn yellow while the veins remain green. This often happens if the plant has been in the same pot for a long time without fresh soil.
What to do: Apply a balanced liquid fertilizer diluted to half strength once during the growing season. If the plant is severely pot bound, consider repotting it into fresh soil.

Yellow leaves on other plants

Find out what's wrong with your prostrate knotweed

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 yellowing spreads rapidly across the whole plant. It is normal for a few older leaves at the base to yellow and drop as the plant grows.

Stopping it coming back

Only water when the soil feels dry to the touch and ensure the plant gets plenty of direct sunlight.

Prostrate knotweed: yellow leaves? Check yours with a photo

Every plant is a little different. Take a photo of your prostrate knotweed 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 yellow leaf?: No, a yellow leaf will not turn green again. It is best to snip it off so the plant can focus its energy on new growth.
Does too much sun cause yellowing?: Usually no, as this plant loves full sun. If it is yellowing in direct sun, it is likely a watering issue rather than a light issue.

Why are my prostrate knotweed leaves turning yellow?