What are these strange white markings on my green bean plants?
My green beans have just sprouted a couple of days ago. They were looking very healthy until now. I've been told that it might be powdery mildew, but it isn't very "powdery" like powdery mildew is. I haven't sprayed these plants with anything, they are just naturally growing. Although, the only other things that has been different, is that we have been getting a lot of rain recently. I have just never seen this before... Please let me know if you know what this is. I really need to know how to treat these plants going forward. If it is powdery mildew... How do I treat them naturally? And what is the best way to deal with it in the future? Thank you so much!
Certified GKH Gardening Expert
You're right it doesn't appear as characteristic of powdery mildew, downy mildew or white mold, but more like a calcium deposit or stain.
In the photos there appears to be a white residue on the soil surface that could be the same material. Was there any soil amendment applied, lime or gypsum where some could have splashed up from the soil surface during rains? Paint, whitewash, cement or stucco cleanup wash-water?
Unless it is widespread on the plants and spreading, causing leaf shriveling, drying, leaf drop and decline, I wouldn't worry too much about it. Keep the plants healthy with good soil and water management.
The soil appears dry and cracking, so get with your watering and mulching program and see how it goes.
@drtreelove Thank you for your response! We had a significant amount of rain yesterday, which watered the ground well. I went to go check on the plants today and where those white markings are (in the pictures I attached) the leaves are completely shriveled. The only thing that is in the soil is a fertilizer we used before planting them. Could that be a problem? The fertilizer?