This weekend I got to play tree doctor as I performed an IVF procedure in our paw paw patch. Fortunately, the procedure was inexpensive, requiring only a plastic bag and a paint brush, and a knowledge of paw paw anatomy. Paw paws can be tricky to fertilize because they are too stinky for bees, giving off a carrion smell that attracts flies. The flies are supposed to pollinate them, but haven’t been doing a great job. Since our trees haven’t borne any fruit yet, I decided to step in.
Paw paws have an interesting developmental life cycle. When the flowers bloom in the spring, they start out as females. Note the stigma in the middle, which is part of the female anatomy.
After a few weeks, the female flowers morph into males,
becoming “hairy” with a coat of pollen.
The procedure was pretty straightforward: I would take some of the flaky pollen from the male flower of one tree and transplant it to the stigma of the female flower of another tree. Fortunately, I had a few male and female flowers on each tree.
Pretty soon I identified my first male donor. He was ready to go and didn’t need any priming.
My assistant handed me a plastic bag, and I began flaking the pollen off the male flower with a paintbrush, letting the pollen flakes fall into the plastic bag.
Then I went to a neighboring tree to find a female flower. “That’s a very healthy stamen you have, Ms. Paw Paw,” I said reassuringly.
With my artist’s brush I dabbed on the pollen flakes and gently applied them to the stigma of the female plant. We’ll see if anything bears fruit. It’s just a matter of time now…
