I already put them in. I could just "feel" the bumbles complaining about not enough blooms when I was there the other day.
So I think I solved the mystery. It's an interesting "karmic" story.
Someone asked me if I made an effort to find the person(s) who lost the money. I said hell no; how would I do that. This person didn't have an answer to that, but I suppose I could have put up a flyer on the gate and ask them to claim the money by telling me how much they'd lost.
First I discovered that the lawnmower guy employed by the school ran over my expensive steel hose. He ruined it. These things are about $60 for a 100' hose. So now I have to buy a new one.
These lawnmower guys are kind of jerks. They leave the gate unlocked when they leave. They run over flowers with impunity. The teacher who founded the gardens and got them off the ground told me stories about how they mowed over bulbs, flowers, you name it. They don't care; they just want to get the lawn mowed and get out of there.
I mean really, what kind of person runs over a flower that some little kid planted?
Anyway, after I discovered the hose I went to the greenhouse. It was very windy and the wind had blown things around, like the covers off the earthworm bins. It then occurred to me that what had happened is the wind might have blown the money out of the pocket of the lawnmower guy. This would also explain the bills where the serial number was found. The lawnmower chopped up a few bills.
The only thing implausible about this explanation is that the lawnmower guy surely had to see his mower going over money floating around all over this huge garden, right? But maybe not.
It's the only thing I can think of and it gives me a convenient rationale for not trying to find the person who lost the money because if I can attribute it to the lawnmower guy, I can call it karma 'cuz he chopped up my steel hose.