What's wrong with my courgettes?

I've got lovely plants, lots of flowers, lots of tiny courgettes but as they grow the are the right shape at the stem end but go all puny and thin at the flower end. Where am I going wrong please?

 

Too cold? Too dry?

 

courgettes need lots of water. we've had a dry spell. they are prolific feeders also. i grow mine on a compost heap. give them plenty of feed. tomato feeds o/k cheers wrinkly 1

 

As above. They are greedy for light, nutrients and water.

 

They are not getting pollinated.
Not much you can do unless you have male and female flowers open on the same morning.

 

Actually that does sound like unpollinated plants. A bit weird as you've got several. we get the occasional unpollinated fruit, but Mother Nature gets the rest pollinated. Maybe try hand pollinating with a cotton bud or similar. I think the stigma is ready to receive the pollen before the flower opens. I've certainly cut a hole in an early flower and hand pollinated while the male flower was open.