A lot of it has to do with temperatures dropping. (and the watering time
) Limes are the most delicate of all citrus. Think of it like the colors of citrus fruit, going backwards as in a rainbow.
Green, yellow, orange, with orange being able to withstand the most cold, and green the least. Kind of in reverse.
Watering it and a sharp drop in temps could cause it to drop leaves, but if you are able to keep the roots warm, it should recover.
Light is also important. I would place it in the warmest room of your house. With a strong Grow light.
Lime is very picky, the most snooty of all citrus, imho.
Ever wonder why one type of lime is called Key lime
? It only grows in the Florida Keys
, the warmest spot in continental US.
We have a Kaffir lime, Meyers lemon, and Dancy tangerine. The Kaffir. even down here; gives us notice.
Regular palm and citrus fertilizer 3 times a year (3 month interval, stop in winter) is good. Do granular on surface of pot. The addition of Osmocote beads 4 times a year helps balance out the other minerals and nutrients needed by the plant.
When outside temps rise above 45 in spring and stay steady, place the plant outside in a mostly shaded area. And if you see roots growing out of pot bottom, time to trim the roots, (yes, with garden scissors including bottom, citrus make a root system that mainly seek the surface, not a tap-root type plant). Rough them up with your hands, revitalize the soil, (replace) and repot into a pot at least 2 inches larger and deeper than you have it in now.
edit: Some of the biggest mistakes I've seen Gardeners make is thinking that a potted plant can live in the same pot, with same soil, no addition of new nutrients and ferts; and never roughing up the root ball upon re-potting.