Trombocino, Trombetta di Albenga No mature females!

I was so excited to grow this Italian Summer squash, but it has been so frustrating! I have seen many (many!) tiny fruits with tiny female flowers on the vines, and LOTS of mature male flowers all over. But the female flowers never get mature enough to enlarge and open. The teeny-tiny fruits with teeny-tiny hard green flower buds shrivel up before there is a chance for this to happen. I have done TONS of reading and research to try and figure out what is happening, with no results.

From what I have read/learned, it does not seem to be blossom end rot. The vines are huge and seem to be healthy. It is very humid here (I live in northern Japan), and it has been pretty hot (80s to low 90s) the last month or so. Please don't tell me I need to hand pollinate (or wake up early enough to see the flowers open). I promise they are much too small, hard and immature to even think about trying to pollinate them (and I've tried with a few that started to get a little bigger). You have to pry open the hard green bud. It doesn't help.

Does anyone have any other suggestions? Has this happened to anyone with this or any other summer squash?

I know what you are talking about. I was happy to get my seed to sprout. Then I was happy to see leaves & flowers all over the place. Beautiful looking plants. Then I was excited to see baby fruits, then they turn yellow & die. This is happening to my tomatoes,cantaloupe,cukes,watermelon,squash. Could it be the weather? Too hot & dry? Anybody know the answer.

Yesterday morning I had my first female flower that matured enough to open! Hooray! It would still be nice to know why it took until late August for this to happen (these plants have been in the ground for months, and they look huge and healthy). Maybe the extra hot weather here affected things?
Anyway, I am thrilled that I have a pollinated little squash on my plant, and am hoping for more.

For "behillman", since the same thing is happening with all of your plants, I would guess it's something environmental that is affecting all of them. Who knows what, but perhaps like you said, they aren't getting enough water in the heat?
What confused me about my squash not developing, is that I have tomatoes and peppers right next to them that are doing just fine. So it has to be something with the squash (probably). In your case there seems to be a larger problem.
I am (obviously) a novice, but that seems logical to me.

I have never had what we call here in Texas, a summer garden, because of the heat & lack of rain. I usually have had a spring garden, but mostly a fall garden. So that could be why I should only plant Okra in my summer garden. It does wonderful. Its growing & fruiting very well. But nothing else seems to like the heat of our summer.

efarnsworth, it sounds like your high humidity could play a major role in your lack of pollination. Excessive humidity will tend to clump pollen, halting dispersal. I also wonder, and feel it is of more concern, if you have ample bees/bugs around as they tend to be the pollinators, normally most active in the morning hours.

"I promise they are much too small, hard and immature to even think about trying to pollinate them (and I've tried with a few that started to get a little bigger). You have to pry open the hard green bud. It doesn't help. "

You shouldn't need to pry open the buds for hand pollinating, let the bud become a flower and it will be very easy to work with. (see pic)

"What confused me about my squash not developing, is that I have tomatoes and peppers right next to them that are doing just fine. So it has to be something with the squash (probably)"

Your tomatoes and peppers are self-pollinizing, not relying on insects to produce their fruit, which is why they are doing well and your trombocino is not.

I hope you have enough season left to get some of those squash, you'll love them. I'd be patient and hopefully you can get true flowers (not buds) to work with.

Best,
Shoe

If I understand correctly, the female buds are falling off before they even open? And your problem was worse when it was really hot, but with slightly cooler temperatures it is improving? That sounds very similar to what I see here in Tucson, where the high heat of our summers causes a lot of buds to abort. I will have squash set buds earlier in the summer before the high heat (for us, 100+ deg F, with overnight lows around 75-80 deg F) that just abort. We've had some cooler weather, and I'm seeing flowers opening again on my watermelons and cucumbers. Peppers and tomatoes go through the same thing, too.

Unfortunately, there's not much you can do about the weather. :(

Good luck!

Does the High Humidity go away in the fall. Maybe I should wait & plant summer squash in the fall. And that goes for watermelons & cucumbers.