Most day length sensitive beans flower during short days, around the equinox. I've grown a few such beans here that were given to me in swaps, and I have no hope of getting dry seed without a greenhouse. In much of California, where the growing season extends well after the equinox, there would still be plenty of time to get a good crop.

However, I doubt that day length sensitivity is the root of your problem. Nearly all of the yardlong beans sold commercially appear to be day neutral... because if they will flower in mid-summer during my long days (at latitude 44 degrees N) and for a fellow collector in Batesville AR (latitude 35 degrees N) they should flower normally just about anywhere. Even commercial varieties developed in the Philippines have done surprisingly well here.

And if you want beans in mid-summer, you would want a day-neutral cultivar.

From the years I lived in California, I suspect that the problem is not day length, but heat. The Central Valley gets pretty hot in mid-summer, which would cause blossom drop for many beans - including yardlongs. Some gardeners in Texas have a mid-summer heat problem too, and can harvest most beans early or late in the season - but not during 100 degree days. In between, you just have to keep the plants alive.

Are you sure that there were no flowers, or did the flowers or buds form, but just drop without setting pods? It might be that you will only be able to get beans during the months of more moderate temperatures. To get long beans in April, you might want to start them early as transplants, and use a variety with a short DTM. I have a bush variety that is very early, but only has pods 10-12" long. For pole varieties, the black-seeded types (such as "Asparagus" and "Taiwan Black") tend to be the first to bear.

I would also suggest that you mulch your yardlongs heavily, and irrigate them more often than your other beans. Unlike common beans (which don't like wet feet) yardlong beans are water hogs; they do their best for me if the soil is never allowed to dry out. Edamame soybeans like those conditions too, so if you are growing any, you might want to place them both in that "extra water" zone.

If you still want to try a day length sensitive long bean, I have one. When I lived in San Diego, I grew an heirloom yardlong bean from the Philippines ("Philippine Purple") that was day length sensitive. It has purple pods longer than "Chinese Red Noodle", that are very slow to develop - which is a good characteristic for beans which are eaten as pods. My own seed is getting pretty old, so it might need a little TLC... but I would be happy to send you a little. Fusion_power (who also posts on this forum) has been growing "Philippine Purple" recently, so if you inquire from him, he might be able to send you more viable seed than mine.

Zeedman,

Wow, you guys are incredibly helpful! Thank you for taking the time to read my post and respond with such an informative reply.

I see now that we are looking for a day-neutral cultivar, as that will not need to wait until the days become shorter...

To be 100% honest with you, the first time we planted the yard long beans was in Sacramento in 2008. At first, we were absolutely shocked because after planting the seeds in March, the vines grew faster and more healthier looking than any bean I have ever planted [30+ years of gardening].

By mid August, the vines had topped 12 feet and seemed to have no stopping sense at all. But there was not even one flower...not even an attempt to produce a flower...

During the last week in August, I was so frustrated [and ignorant] that I told my wife, "I am pulling up every one of these Asian long bean vines because after waiting 6 full months, there is not even one bean!" She simply told me I needed to be more patient.

Then came September, and the greatest gardening shock of my life...

Those Asian long beans began to produce some of the most lovely and incredible looking flowers I had ever seen. Then, from mid-Sept-Dec, we had a non-stop massive harvest of absolutely delicious long beans ever.

So I suppose I became a believer after that.

But, I would desperately like to find a variety that will produce all summer long instead of waiting 6 full months before harvesting even one bean.

I hear you about the summer heat, but the heat really is not that bad here...I have never seen the summer heat damage a bean plant before. The summer heat here has caused nearly every tomato plant flower to wilt [not set fruit] on rare occasion in a manner that our harvest was reduced for about a 2-3 week period.

Zeedman, I appreciate your offer to try those nice Philippines Purple variety. We would like to take you up on your offer. Please let me know the costs and we would be glad to accommodate you.

Last, we are still totally interested in this "day-neutral cultivar" you mentioned. Can you please direct us to a site where could purchase some?

Last year I remember finding a site that specifically stated it was modified to grow and produce and did not need to wait for shorter sunlight days.

Only problem is, now I cannot find the site again no matter how hard I look.

I thought it was Echo, but can't find it there either.

Soar

Look for a variety called Chinese Red Noodle. It is commonly available and is reasonably productive in most U.S. climates.

I have a limited amount of Philippine Purple seed but could send you 20 or 30 if needed. Zeedman can send you some of his or let me know and I will mail a pack.

Dar

Dar and Zeedman,

Ok, we would like to accept your offer of some of those Philippine Purple Seed. My wife is from the Philippines so she will be very happy.

Please let me know how I can get our mailing address to you and also how we can reimburse you for the seeds and mailing costs.

Finally, if anyone here knows where we can purchase the Asian long bean seeds that is "day-neutral cultivar", please let us know.

We have begun our spring planting already, even though it is still winter...yep, 6-7 20'x8' trellises of the Super Sugar Snap peas, and over 1,000 of the red, yellow, and white onions. Also, we just started all our leaf plants such as lettuces, spinach, Pakchoi, Aruga, etc.

Our Swiss chard plants, planted nearly one year ago are still growing like gangbusters...and Russian kale grows here all winter long as well. Yummy!

Have a great day everyone!