Concerning the second picture titled "Here's the same Meyer Lemon in flower." Ninety-five to ninety-six percent of the flowers shown in the second picture, will fail to produce fruit, and drop from the tree; or will set small fruitlets that will also be eventually discarded. In the end, the tree will retain only 1 to 3 percent of all the fruit that could possible be produced from all the blooms. Here is what I do with Meyer Lemon trees.
Note: this procedure pertains to my containerized Meyer Lemons only. ------------ Each fruit that a citrus tree produces, and retains until maturity, (Meyer Lemons included), draws all of its nutrition (energy) from the five closest leaves on the stem. Normally a Meyer Lemon blooms in clusters, with one of the blooms in the cluster becoming the biggest and dominant bloom. I select the dominant bloom, and pinch off all the remaining smaller blooms in that cluster of flowers. I do this to each flower cluster for each five leaf area of the tree. Therefore, each fruit becomes larger, juicier, and more fruit are retained by the tree. This is because each fruit is receiving energy from its own five leaves, and is therefore not competing as much with other fruit on the tree. This still does not protect every fruit remaining on the tree, but it works very well in obtaining high quality fruit, and many more of them. This also gives a much more balanced , and more of them, especially on smaller container trees. - Millet (1,113-)