Fruit Set in Tomatoes including those with and without obligate outbreeding

[William S.]

It's been a cold wet spring. With occasionally a few hot days. The fava beans have fruit set finally far down on the stalks.

I think the switch is flipped though and dry season is starting. 80s...

Tomatoes however- well there are a few. I spot green tomatoes on Wild Child, Exserted Orange, and Payette. Though literally only on ~3 individual plants so far.

Some of the domestic blossoms have aborted because of the weird weather.

I didn't plant anything like Siletz which forms it's first fruits without pollination. Too bad. This may have been the year to plant it!

The Bombus are about but they aren't really visiting the tomatoes yet. Soon I suppose.

Lots of flowers no fruits yet on most tomatoes including the obligate out crossers. Those won't set fruit till the Bombus get into tomato mode. Every year they do this. Maybe the thill of Monarda fistulosa has to fade a little or maybe brood needs protein from pollen at a certain stage. Dunno why. Guess it gives time to see which ones abort and do not self.

[Steph S]

The bumblebees that you see early in the year are the queens that overwintered.  They have no workers yet, and they need both nectar (for themselves) and pollen for the brood they are bringing up.   The queens never touch my tomatoes in early season here, even when other flowers are scarce.  They'll do a flyby speeding along in search of something good, never stopping for any of what we've got... That is because tomato flowers have lots of pollen but no nectar.    Once the first brood have hatched these little bees will work the tomatoes really thoroughly, to bring home the abundant pollen for the next brood.   
OTOH put out pepper plants or brassicas that bolted, and the queens will be humming 'thank you thank you!" and gobbling it up.