Anney,

It is a fact of life. The hotter it gets, the lower the production. But there are a few caveats.

1. It is variety dependent. Rattlesnake is about the most heat tolerant of the available common pole bean varieties. There are very few that are more heat tolerant and many that are similar such as Kentucky Wonder. On the other end of this spectrum are varieties that have almost no heat tolerance. If you grow various wax bean varieties, you will find that most of them really suffer in the heat.

2. It is species dependent. Lima beans (Phaseolus Lunatus) on average are far more heat tolerant than ordinary beans (Phaseolus Vulgaris). By comparison, runner beans (Phaseolus Coccineus) are much less heat tolerant and rarely mature here in the south.

3. It is water dependent. If you can water your beans during the worst of the heat, you can extend production significantly. This works regardless of variety.

4. It is temperature dependent. Most beans do great up to about 95 degrees. Once you get above 95, pollination becomes an issue. Even Rattlesnake misses out once you get above 105 degrees.

So, if you can combine the right variety with supplemental watering, you can extend production significantly.

DarJones

Dar

Thanks for the info!

I've either been growing varieties that haven't suffered in the heat, or have kept them well-watered, or just haven't noticed decreased production in really hot weather if I had so many other bean varieties to harvest, cook, and freeze.

Anyway, most of the varieties we like seem to be pretty heat-tolerant, though I don't know about Fortex beans or Roma pole beans. But limas and cowpeas are probably okay.

I smiled about keeping the beans watered and their tendency toward blossom-drop in high Southern heat. I read a site last year about an automatic watering system for large acreage farming that included a soil moisture sensor. As is obvious from the "automatic" part, when the sensors indicated low soil moisture at whatever depth the operator determined, the water went on.

The claim was made that when plants are watered, their vascular system uses the water to cool the plants off in high heat, creating a kind of internal "air conditioner"! (The crop may have been tomatoes, don't remember.) It appeared that the author meant the roots functioned to bring the water up through the stems throughout the plant to cool it, not the leaves from an external spray.

The claim was made that when plants are watered, their vascular system uses the water to cool the plants off in high heat, creating a kind of internal "air conditioner"! (The crop may have been tomatoes, don't remember.) It appeared that the author meant the roots functioned to bring the water up through the stems throughout the plant to cool it, not the leaves from an external spray.

It's bascially evaporative cooling, the same way sweat cools you off. And it goes either way, through transpiration or through water applied to the leaves evaporating (same way water sprayed on you would cool you off).

Basically, being hot and being dry do similar things to plants (in general, at least), because heat causes more water to transpire out of plants, so either way the plants have less water.

Watering them more does help, but then there's things like your utility bill and any city water restrictions to consider. Because of those things, I am mean and don't water my plants a whole bunch in the summer. They just have to tough it out, LOL. Some plants, like cowpeas, okra, sweet potatoes, and hot peppers, can take it. Others like beans, squash, melons, and tomatoes usually quit producing and then pick up again in September when it cools down.

Anyway, I digress. Yes, my pole beans do slow down in the hight of summer, but they're one of those plants where, if they survive the summer, they start producing again in the fall.

I've grown pole lima beans in the Washington DC area since 1976, both large seeded and small seeded varieties. My favorite small seeded variety is Carolina.
I've grown various large seeded varieties also including Burpee's best, Prizetaker, King of the Garden and one other that I forget. Some years I have had trouble with pod set with large seeded varieties. In Tallahassee in 1985 I had almost total set failure with Prizetaker but Carolina set in July. Nothing set after August although
vines grew well until December frost.

In the DC area since 1987 Carolina has always set reliably and large seeded varieties set enough so that gaps in production might be due to heavy pod load from previous sets. This was the case through 2009.

Summer 2010 and summer 2011 were 1 degree warmer than any previous summer since 1874 with mean lows in the low 70s and mean highs in the low 90s and extended periods warmer than that. And these two years I had an alarming total crop failure both summers with Carolina and Florida Speckled Butter, though the vines grew well. After two months of dropped flowers I started getting sets the second week in September 2010, too late to mature before frost killed them. In 2011, cooler weather began the third week in August and I got sets and a decent single harvest before frost in early November.

Other gardeners in my rental garden area (Beltsville) who had grown beans for many years also failed in 2010. No one else grew lima beans in 2011.
There were some short term drought problems but that's typical in summers here and I don't think water stress caused the failures. These were also my
two worst years for corn (after I got my earliest ears ever June 8 2010) but
corn problems were due to an undetected phosphorous deficiency in the
soil and to a new species of stink bug that is spreading in this area. Once I used a different fertilizer with more phosphorous my later corn yields were okay.

My question is, has anyone else in the middle atlantic region, tidewater Va or the Carolinas, or the Southeast U.S. also had problems growing lima beans these past two summers after a long period of success? Farmers market producers in my area who grow in more rural locations did not have problems. I am a home gardener and grow veggies because my kids will eat mine more readily than they eat store bought ones. They don't like lima beans generally but consider mine a delicacy.

I'm in middle GA (Eatonton area) and definitely saw what Dar describes. Rattlesnakes and Hilda Romanos kept growing, but most of the others (winged beans, marchand, Kentucky Wonders) pretty much went on vacation despite lots of watering. I have raised beds and most beans were planted together (sharing one long bed). The Rattlesnakes slowed down quite a bit, the Hildas some, the others just sat there until September.

On the other end of the spectrum - we had our first real frost last night and I'm guessing that the Hildas have stopped growing now - I picked beans three days ago.

I've not had any luck growing green beans here in AZ so far and I've talked to a couple of gardeners who have. Usually they have to start seeds in Sept to get beans pollinating after things cool off.
I do, however have great luck with long beans. I've found the green long bean, asparagus bean, tastes very similar to regular green beans when picked at about 12-15 inches but still thin and crispy. What I do is steam them instead of stir frying. Production is amazing if well watered, at times I'll pick a couple of quarts everyday off of a very small trellis, 6 feet long and 5 feet high.
What I need to experiment with next yesr are some preserving techniques. Has anybody tried pickling long beans?
Also, I haven't had any luck with Limas until fall. They don't seem much more heat tolerant than regular beans, although I'd like to get ahold of some of those black jungle beans.
Southern peas do very well here. Red Rippers and PEPHs did crazy despite the hottest August and an aphid infestation.
What I need to try next year are some pr

I have had similar experience here in east central Mississippi. Common wisdom is that our hot nights have a great deal to do with plants struggling in our high heat and humidity.

This year, I am planning a new bean strategy. Instead of planting a variety of beans from the get go, I am going to plant just pole beans as quickly as the ground warms and in all the space I can manage. My two favorite TASTING beans are Louisiana Purple Pod and Fortex. They will do just fine until temperatures hit above 93 or so. Typically that doesn't happen until early July (this past summer it hit in June. I got three pickings only.).

Then when the intense heat moves in, I will pull out the pole beans and plant cowpeas. They love the heat and will make a good crop in just six weeks.

In mid August, I will pull the cowpeas and plant pole beans again. They will come up like gangbusters and grow well in August heat. They will start blooming about the time our cooler fall weather begins to arrive in September, at which time they will start setting beans. So, I should be able to pick until frost in mid November. (Limas do well in the heat too, but I like cowpeas just as well and they are easier to shell.) I have done the fall planting thing the last two years and those beans taste even better than the early summer crop.

In addition, I plan to try Red Noodle beans in the heat of summer this year. I have read on these forums that they do fairly well in southern heat.

Would shade cloth help in the heat?
I have Black Jungle Butter Beans & can not wait to see what they do in the HOT Summer.