That totally depends on you and your growing skills. Not on the plants.

Silica; There is a lot of truth in your statement. Do you have any tips. Perhaps rootstock choice may require different growing tactics. Even each variety of kumquat may need specific care to do well. When in writing, I'm "all eyes"

The most finicky tree I know if your mix is not very porous , you don’t provide an abundant amount of light and water properly. Oh yes , don’t forget to fertilize since they eat like pigs.

living room lemons, from what you wrote above concerning your fertilizer practices, your tree's yellow lemon veins is most likely caused by a lack of enough nitrogen.