Pole Bean Problems - Ask Extension
Hi,
Generally pole beans do amazingly in my garden, but this year is different. They have not reached the usual height, they have good looking leave...
Knowledgebase
Pole Bean Problems #878517
Asked July 24, 2024, 12:19 AM EDT
Hi,
Generally pole beans do amazingly in my garden, but this year is different. They have not reached the usual height, they have good looking leaves towards the base but the upper leaves are small and curled in with yellow edges and exaggerated veins. They are flowing but mostly not producing fruit. Some of the growing tips are also brown. I noticed these changes during the 100+ hear wave a couple weeks ago but the look of the plants doesn't seem to resemble heat stress in online pictures.
Thanks for your help!
Benton County Oregon
Expert Response
Thanks for contacting "Ask Extension" with your question about your pole beans. From your pictures, I suspect this is herbicide damage. Phenoxy-type herbicides, such as ones containing 2,4-D, are most often the culprit. These herbicides are absorbed by the plant and transported to its growing points, and can cause damage at just 1/100 of the label rate. Unfortunately, they are quite volatile (especially the ester types), and can drift up to a mile or more, especially with even relatively light (10 mph) winds, and some formulations can even re-volatilize for days after spraying, when temperatures are over 80 to 90 F degrees. Because air currents are usually quite variable, damage can be spotty, and may even “skip” over one portion of a field, making it more difficult to determine the source.
Hope this helps!
Hope this helps!
Yikes!! Thanks Deb for your response! I did have a neighbor spray out some blackberries not 15 feet from these beans on the other side of a wooden fence. Would you suggest giving the whole plants a good drenching to try to rinse it off? My irrigation is from small sprinkler heads and don't wet anything above about a foot.
Thanks again for your help!
Rinsing off the plants with water is effective, but it has to be done within 3 hours after contact with the herbicide. The only thing you can do now is to keep the beans as healthy as possible by giving them adequate water and fertilizer. (But don't give excessive amounts of either!) You want to give your plants the best chance possible to recover.
If your neighbor is receptive, you might give him the following recommendations to avoid herbicide drift.
Happy Gardening!
If your neighbor is receptive, you might give him the following recommendations to avoid herbicide drift.
- Never spray when it is windy. Any herbicide can drift due to the slightest breeze. Drift can be reduced by lowering sprayer pressure to produce coarse spray droplets.
- Keep spray boom or nozzles close to the ground and spray only the targeted area.
- When applying herbicides containing 2,4-D, use only the amine or the low volatile formulations and spray when air temperatures are below 80F.
Happy Gardening!
