A Gardeners Forum Forums Gardening Reference Gardening in 2004 Help! Something wrong with my beans!

Yesterday, I went to check my bean plants (don't know the name--definitely a "rarer" variety) that are sending vines everywhere, blooming, making beans, etc. But I was shocked to that about half of the leaves have suddenly yellowed. Most of the yellow leaves are older ones, but some new leaves are yellow too! They weren't yellow a few days ago.

I fertilize about every week or two. They receive a few hours of good sunlight each day. There are five bean plants in a hole in the ground filled with lots of potting soil. I water when dry.

I don't know what's causing this. My bean plants look dreadful now!

Thanks for any help!

Hi lily,
There are a couple of possibilities that come to mind. You say that they are planted in potting soil. Potting soil is primarily peat moss and is usually sterilized and contains very little or no nutrients. Once peat moss dries out it is difficult to wet. Peat moss also has very little nurtients and, though you are feeding often, this could be the cause as well. Once they set blooms your fertilizer shouldn't be high in nitrogen. Peat moss is also acidic and beans tend to like a more neutral to alkaline soil. Most compost, if well aged, would be more neutral in ph. Beans tend to have shallow roots, so you might want to mulch with a couple of inches of compost. That will help to retain moisture as well and add good microbes to your soil. Take a look here for some interesting info.

Cornell U - Pole beans
http://www.ondelmarva.com/peat.html

Newt

did you notice any little white powdery spots? my sugar snap peas did the same thing- all of a sudden it got white powdery spots and then suddenly turned yellow and then brown and shriveled up. it was powdery mildew. probably because of the cool wet summer we've had. i was sort of full of the sugar snap peas anyhow though. i think they have some fungicide stuff at wal-mart that says it stops powdery mildew in 24 hours. i don't know of any other way to stop it if that's what it is. maybe phil or raye can help you with organic stuff.

All of the advice above are possibilities! You stated that your beans have been producing well...For how long? Maybe they are about done with producing. Beans will usually produce as long as you pick them every three days or so, leaving beans to mature on the vines will make them "do thier thing" and complete thier life cycle, which will cause them to slowly yellow from the base up. Rare beans....tell me more
Beans do not need nitrogen, as thier roots "fix' nitogen from the atmosphere, and the peat could definately cause you a problem; however, if you have enjoyed an ample harvest, they have probably just reached thier limit...what has your weather been like?

Hi,

Thanks for all the help!

I checked the leaves. No mildew or anything...just some holes the beetles made. But they've disappeared weeks ago, so no problem. Now they look even worse. Still producing some beans, but so many leaves fell off! They're pale green and look very bare now. Maybe they have reached their limit! I planted them around April and they've been producing since May.

I did let some beans make seeds, so I can get next year's beans. Little did I know that I would end up with so many surplus seeds (maybe that drained the energy?). Ooops! I did get some good harvests. They have this special flavor and taste quite good!

The weather has been hot, humid, and sunny most of the time. It rains, but not enough so that the beans won't be thirsty. About the peat...maybe I should use something that has less peat in it...

I don't know the name of the beans (a friend gave it to me). They do climb with their long, purple stems. The flowers are bright magenta (or pink). The pods are four inches long, a little over one inch wide, and not very thick. Color of pod is greenish with a reddish tinge. Dried beans are black with white edge. It's nothing that I've ever seen in any grocery stores, so I guess it's "rare". Any ideas on what it can be?

Thanks again!