This is the first year my plumies stayed outside in a greenhouse and not be brought indoors. I keep the heater on inside and it doesn't drop below 55ยบ inside at night. It is much warmer in the day. But they are acting weird. The bottom leaves have yellowed and a bunch have fallen off. Yet there is new growth on the tops. Some are not losing leaves at all : The pudica look good and the pink pudica looks great. I also have a white(?) noid that is not dropping leaves at all and the Riveria Rainbow is also pretty green, though it's broken babies in a separate pot are naked. What causes this irregular non-uniformed leaf drop?