Because none of the flowers 'set', hence no fruit. Are you growing these in the greenhouse Hywel? If so you may need to d oa little pollenating yourself next year.

Thanks. Yes they are in a perspex shelter ... like being in a greenhouse really. There is no door, it's just an open space but there must have been a shortage of insects. It's been a poor year.

You can say that again Hywel.My kale got eaten by caterpillars before I noticed, chard went to seed and so did spinach, squashes dead loss, but my one cucumber plant did produce two cucumbers...Add to that my stolen gooseberry and rhubarb crops and its not been the best of years in the eats department. Hurray for the leeks that seem to be doing fine so far...

Indeed it has Hywel

Thank you both ...

Glad your leaks are all right Sue !

The nice thing about tomatoes is that if they need pollinating, you don't have to go crawling around the tunnel with a paintbrush. Tomatoes are perfectly capable of pollinating themselves, but they just need the help of a little shake. Just go around in the morning, gently tapping the trusses on their tops.

That sounds easy, thank you :)

Hywel, Is your greenhouse temperature controlled? Tomatoes will not set fruit if the temperature is above 90F or below 50F. You need to be in the 'zone'.

Thanks ...
No it isn't controlled. There's no door anyway.
The temps here have been between 18 and 25C all summer ... (don't know F sorry)
falling a few degrees in the night.
The greenhouse faces west so it would probably rise to about 30C in there on sunny days.

Most of the trusses have tomatoes, but a few haven't.

30C converts to 86F so you are in the 'zone'. At least that rules out a temperature issue. The next big issue is pollination. The bees probably can't find your tomato blossoms.

I like Tugbrethil technique above with the painbrush. A Cotton swab (Q-tips) also work.

I usually plant sun flowers or zinnias near by to help draw in more bees.

I'll plant those next year :) Thank you ...