If it was a race then the lemon tree would be taking a nap, the kaffir lime tree would be strolling along looking at butterflies and the key lime trees would be space men with rocket packs.
It probably has to do a lot with the placement of the plants. The more they grew the more sun they have. The poor lemon tree is sitting under the pecan tree which gives it maybe 2 hours of sun a day.
Even though I still need to split up the key lime trees (all being in one pot and all) they still shoot up being in full sun all day and having plenty of water (from the hose).
I think I'll swap them up and see if they change growth. Probably sounds like a no brainer, but who knows. It might also be that the smaller plants are growing faster which is also true.