Exception error when choosing the 'fertilize all' option

Adding to this, in my current save I only have dragonfruit and growfruit.  I thought perhaps it was because the action wasn't queued but now I just had my sim fertilize all by clicking on the growfruit tree and I got the exception.  When I click on the dragonfruit to fertilize all it seems ok.    So... perhaps it's just from clicking on the growfruit??  Also I am using growfruit as the fertlizer.