I have the same problem with my zucchinis -- the female flowers come on first with tiny zucchinis attached, but they never open and there are no male flowers. The plants are healthy (planted from seed from a local reputable seed company) and have no powdery mildew or insect damage that I can see. My question: Should I pinch off at least a few of the too many female flowers to lessen that stress on the plant to see if it might help more male flowers catch up? Also, I read somewhere that pinching out some of the outside stems that have no flowers, to sort of force new growth of stems that supposedly will tend to have the opposite gender of flowers. Any truth to this?

I have the exact problem - vigorous vines but no flowering for 2 years now in the same location that 3 years and before I had many beans. My treliis is actually an arbor than can be walked under @ 7 feet high. My pH is 7-7.5, micronutrients are not lacking, N is low but P &K are excessive. Am adding sulfur to lower pH but suspect the problem is something else. I've checked into toxicants from tree roots (not too far away) but not sure on that. I regularly add hardwood leaf compost mixed with grass clippings so am wondering if that is a factor. Sunlight is 6 hours a day so don't think that's the problem. We had severe Spring droughts for the past 2 years, but I've watered every other day though wonder if I was getting enough down for uptake during the bloom period. Temperatures were excessive - mid 90's- so am suspecting that as the main culprit. Am to the point of pruning the layering vines in hopes of getting results when things cool in the Fall. I've typically had excellent blooming & bean production just before the first frost. Other experiences? Advice?

Hi guys thanks for all your help- I am not going to repost in the other forum at this time b/c I think I got some very good information here. I went to walmart today and they were out of cactus mix. Sigh. They did have a bag of perlite tho- but I wanted to check with you guys first if this is the correct thing to buy, and if so- what do I do with it. I have a bag of miracle grow potting soil- I am assuming I need to mix these two together. I also have some small gravel- about bean sized. I plan to put him in a terra cotta pot since plastic holds the water and doesn't breath. I could use some instructions on the dirt mix tho- and as an aside- I purchased a succulent that needs to be repotted- do I use the same type of soil for him? I also have two lemon trees I grew from seed that I wanted to put into citrus mix, however they didn't even carry that this year. No they don't ever grow lemons, sometimes they flower but that's ok- the leaves smell really nice.

Hmmm the cestrum nocturnum that bloom here the best seem to be the ones on the front flowerbed and they get light from the windows in the house at night plus the porch light that stays on most of the night. There are 5 huge ones out there. I have more in the back yard and they flower pretty well back there in total darkness too. They do bloom on new growth. I cut mine back (if they didn't die back in the winter) then feed them a bunch of miracle grow and top dress with composted chicken or rabbit manure. They seem to flower best in full sun. If you keep trimming them back a little after each huge flower flush you can keep them blooming till frost. I keep a few in pots as well Hawk Moths love the nectar I do also have an Indian Night Jasmine Tree (Nycanthes arbortristis) that seems to like total darkness at night. It also blooms on new growth. This post was edited by sultry_jasmine_night on Mon, Jun 10, 13 at 11:29