Wednesday, July 18, 2007

ugly bugs on pole beans

blighted pole beans pole bean bugs
pole bean webs pole bean trouble

OK. Some more ugly pictures of my pole beans. I was asked some questions about what's really going on, so here are some close-up photos.

I guess I see thrips and spider mites. Some mite webs. Also mottled, puckered leaves and fruit. I noticed black aphids earlier but they're gone now. The problem is ONLY affecting my 3 types of pole beans, one of which is way on the other side of my house. No problem with my 3 types of bush beans planted nearby (odd).

So my guess is the real problem is a mosaic virus and the bugs here are just feasting on the weakened plants. I've sprayed in previous years for mites on eggplants and have found that this made the mites worse (it reduces the bugs that feed on the mites). I think the real problem is not usually the mites.

So, I'd love any suggestions here. My plan - no spray. Just remove the pole beans and avoid planting any more this year. I'll plant bush beans instead.



Anonymous said...

Hi there, I've been reading your blog for a little while now. I really applaud your decision to avoid chemical pesticides, (and you're right that they don't actually work long term, either).

It's might be too late for these plants, but I wanted to share some info about natural ways to fight pests like aphids for the future. I use a concoction that consists of orange peels, cayenne pepper, garlic, and castille soap that works really well. I just put it all in a jar of water and let it steep, then strain and pour the liquid into a spray bottle and spray directly on the aphids. (If it has been steeping a long time, then I would dilute with more water.) It works fairly well, and it only kills the bugs you want to get rid of, and doesn't hurt the plant at all. (Apparently there are chemicals in those ingredients that soak through the soft-bodied insects like aphids and kills them.) It doesn't get rid of all of them, of course, but it can keep minor infestations from turning into major ones.

I know I found a bunch of different recipes for this on the internet a while ago, but I no longer remember where. I'm sure a google search would get you lots more info, though.

Best of luck with your garden, it looks wonderful!

kathy said...

Sounds like a good concoction to remember is I get an aphid infestation again. Though it sounds like it takes some work to collect, steep and spray those ingredients.

I really don't think it make sense to spay pesticides just to grow a few pole bean plants, when I can just grow another variety (bush beans) instead. The plants are out now and I'll seed lettuce in their place tomorrow probably.

Anonymous said...

Of course if bush beans are what grow well, that's what you should plant. It doesn't seem logical to me that just because they are bush beans means they are more resistant to the mosaic virus or the mites. I suspect it may be more the variety of bean rather than bush or pole.

You've probably mentioned the varieties you're growing, but I don't remember what they are. It might be an issue of old varieties vs. new ones. Newer varieties are probably more likely to have resistance to the virus.

Otherwise, I think you have the right plan.

kathy said...

Thanks Patrick. I always appreciate your advice. I think you are right! The ones that succumbed to the virus were three heirloom varieties. (I was looking forward to these less common varieties :( Oh well.)The ones that grew are newer.

I did plant another pole bean variety today (it looks like a varitey of pinto bean, though the package is mostly in Italian) just to see if its OK. Also some more haricots verts, which have been doing great. Just now I googled and apparently these are resistant to common mosaic virus. I will watch for resistance in the future.

Anonymous said...

Help! I am a new gardener, and I decided to grown some Green Beans in a small patch in my front yard. Thier pole beans (I think?) and they are getting these little holes in them, and its getting worse! I really need some help here.
-a novive in need of some serious help.

Anonymous said...

To anonymous.... do you see anything making the holes during the day? If not, try going out after dark, like 11 pm or so and look underneath the leaf. I had troubles and the diagnosis was either a beetle or snails. When we went out at midnight, snails everywhere!!! Big and little (baby slugs, you could say) For that, try Sluggo, environment friendly. For the other, try and catch one and take it to your garden center. Those bugs sure are sneaky! Good luck.

Anonymous said...

This is much after the fact, but I had some pole beans in a raised bed this year that had yellowy edges and I found out that a magnesium deficiency can cause that. i tried a VERY dilute spray of epsom salts on the leaves and they improved.

I had ccrinkly bean leaves the year before and decided it might hsve to do with herbicides in the community compost i got -- it was supposed to have no grass clippings in it, but I thought it might have been from an herbicide that is used in some lawn pre-emergents (dicamba). I didn't put anything on my lawn but maybe somebody from the town put grass clippings in their town leaf pickup.

Herbicides are salts, and I notice you have tip burn on some of the leaves. Even though you are not using them if your garden is downslope from a neighbor who uses them you could get runoff with such chemicals in it.

If this happens again, sometimes I have been successful using Google images and putting in search terms to find symptoms of e.g. phytotoxicity (plant poisoning) or nutrient deficiencies.

Thanks for the blog - fun to read.