Yellow Spots on Bean Leaves - Reasons and Treatment
By Parvez Akhtar Pasha | Sep 04, 2025
I usually grow veggies for myself, but bean is something that I grow commercially. People like me understand how much effort and time it takes to grow something productive from your land.
For the past few days, I have been noticing yellow spots on my bean leaves. I have been a gardener for a long time, and I know why this is happening. I thought it would be worth sharing what I know with you.
Note: I can not look after all my lands and plants at the same time. But when a plant disease like this catches my eye, I become proactive in treating my plants.
There might be multiple reasons behind the yellow spots, but I will teach you how to distinguish them by just looking at the spots.
The two most common reasons are:
- Bacterial Blight.
- Specific nutrient deficiency.
Specific nutrient deficiency may cause yellow spots on bean leaves
The picture you are seeing:
This is due to a lack of nitrogen, magnesium, or potassium.
Now the hardest part is to identify which one of these three nutrients is deficient.
If you see yellow spots on older and lower leaves first, it means your plant lacks nitrogen. Feed nitrogen-based fertilizer.
Yellow spots on the middle or lower leaves mean your plant needs more magnesium. You will notice yellowing between veins. Veins will stay green.
Yellowing older leaves is normal, but yellow spots are not normal. If you see yellow spots on older leaves, feed potassium-based fertilizer.
Bacterial blight on bean leaves
It's easy to identify bacterial blight.
It will start from the normal yellow spots on the leaves. ( It may occur on new leaves and older leaves both)
With time, the yellow spots will turn dark and then brown spots inside.
For an instant solution, use a copper-based fungicide.
I always recommend my gardening friends to rotate their crops. This will reduce the fungus attacks.
I know if you search the internet, you will find at least 5 more reasons that cause yellow spots. I hate making my readers confused, and love to provide the most common reasons and working solutions for them. Help me bring more content like this to you by just subscribing to this site. It's really free!
