Q.lemon tree
i planted a lemon tree in a barrel.its doing well..but..there are lots of tiny lemons on the tre ,they grow a bit ,lots fall off and the ones that stay on the tree ripen when the lemon is still the size of an acorn…why are they not growing to a larger lemon…i have had lemons from that tree that were larger

How often do you fertilize? You will need to do this at least once per year. I recommend at least twice for container, but it is not completely necessary. This is usually due to a lack of potassium and phosphorus in the soil. It is also best to apply dolomitic lime and iron sulfate to the soil when you fertilize. This will save you much trouble in the long run.
Here is an article for more information: https://www.gardeningknowhow.com/edible/fruits/lemons/growing-lemon-trees-containers.htm