I realize the word tree might be a bit of an overstatement for this plant, might be more like a Lemon "shrub". It has many open flowers and lots and lots more buds growing each day.
I had mentioned in an earlier post while reading up on the care of indoor citrus that since there wouldn't be any pollinators indoors we'd have to hand pollinate. From what I could find on hand pollinating a small artist's brush was the best thing to use, although I found one person that suggested using a finch feather. We decided to go with the paintbrush. Here you can see the brush being carefully brushed against the pollen in the flower.
And look who my little bee is... The Littlest Gardener was very excited to pretend she was a bee. I told her how bees pollinated the flowers by visiting different flowers and carrying pollen from one flower to another. She worked very intently on making sure she got to each flower.
I'm sure each flower was pollinated as if an entire hive of bees had been on the little tree. I figure this is our little indoor winter experiment. If we get fruit it will be very exciting, otherwise it was a good lesson on how important the different pollinators are in the world.
I did read that some people hand pollinate the flowers regularly until the flowers are spent. My little busy bee and I will keep you posted on how our lemons do. Until then I will be stopping by regularly to breathe in the wonderful smell of lemon blossoms.