pole bean leaves - sign of a problem? - Ask Extension
I planted pole beans as in every year, later than usual because of low temperatures in late spring, but all came up very quickly. Soil is very well dr...
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pole bean leaves - sign of a problem? #801514
Asked July 16, 2022, 4:49 PM EDT
I planted pole beans as in every year, later than usual because of low temperatures in late spring, but all came up very quickly. Soil is very well drained with addition of compost - this year it is Fort V. Bed is well mixed, fairly homogeneous. I did not do soil tests. I have been very careful to keep them adequately watered, and they are mulched with straw.
On the early (lowest) leaves of a few plants, dead dry areas developed when plants were very small. At present, these spots are dry and brittle. Rest of plant (new leaves) seems OK. IS THIS AN INSECT, DISEASE, SOIL CHEMISTRY, WATER - what?
Also see other photo - shows leaves on just a few plants with "crumpled" and pebbly looking areas on both older and newer leaves, IS THIS AN INSECT, DISEASE, SOIL CHEMISTRY, WATER - what?
Lamoille County Vermont
Expert Response
Hello Ed,
Thanks for contacting the Extension Master Gardener Helpline! It looks like you entered this question twice so I am closing this one and our volunteers will get back to you shortly. Thank you.
Hello Ed,
It looks to me from your pictures that your bean plants have a bacterial leaf disease, such as 'bacterial brown spot." There are several ways that this comes on board. It can start by moisture on the leaves during hot, humid conditions, planting in the same spot year after year, handling plants when wet, can be seed-borne, can over-winter in plants left in the garden, for starters.
You can mitigate the problem by picking off the affected leaves and discarding them (don't leave them in the garden or put in your compost ), rotate your crops (don't put them in the same spot in your garden 2-4 years apart), bury (non-affected) plant residue in the garden at season's end, make sure you are using seed from a trusted source. I have included a link to an article that you may find helpful as you gain knowledge about this problem(that happens also with peppers or tomatoes), so that you may avoid this problem in the future.
https://extension.umn.edu/plant-diseases/bean-insects-and-diseases
The leaves in the second picture could by the result of a mottle virus, which sometimes can be spread by handling or even aphids. The mitigation is similar to the bacterial problems but it may be difficult to pick off all the affected leaves. Your will want to not handle the leaves, secure your season's harvest, and gather your plants into a plastic bag and discard at the end of the season. Following is a link so you can learn more.
https://extension.umn.edu/pest-management/bean-pod-mottle-virus-soybean
Hoping for success in your garden.
It looks to me from your pictures that your bean plants have a bacterial leaf disease, such as 'bacterial brown spot." There are several ways that this comes on board. It can start by moisture on the leaves during hot, humid conditions, planting in the same spot year after year, handling plants when wet, can be seed-borne, can over-winter in plants left in the garden, for starters.
You can mitigate the problem by picking off the affected leaves and discarding them (don't leave them in the garden or put in your compost ), rotate your crops (don't put them in the same spot in your garden 2-4 years apart), bury (non-affected) plant residue in the garden at season's end, make sure you are using seed from a trusted source. I have included a link to an article that you may find helpful as you gain knowledge about this problem(that happens also with peppers or tomatoes), so that you may avoid this problem in the future.
https://extension.umn.edu/plant-diseases/bean-insects-and-diseases
The leaves in the second picture could by the result of a mottle virus, which sometimes can be spread by handling or even aphids. The mitigation is similar to the bacterial problems but it may be difficult to pick off all the affected leaves. Your will want to not handle the leaves, secure your season's harvest, and gather your plants into a plastic bag and discard at the end of the season. Following is a link so you can learn more.
https://extension.umn.edu/pest-management/bean-pod-mottle-virus-soybean
Hoping for success in your garden.
