Should I cut off all the branches after the lily falls in winter?

Don't trim. Because the petiole will wither slowly,

Just maintain it as usual.

Now the seed ball absorbs nutrients through the petiole. When the seed ball absorbs enough nutrients, the petiole will naturally wither.

After the flowers wither, they will move to underground bulbs to grow. As long as there are green leaves, the bulbs will be raised and strengthened to prepare for future flowering.

Even after the lily completely enters dormancy, it is best not to pilling, but to turn the flowerpot to a cool and ventilated place and raise it roughly.

It should be noted that in the case of green leaves, if the temperature is suitable, topdressing can be done as appropriate to make the green leaves last longer; After complete dormancy, no topdressing is needed.

New buds will sprout next spring, and after the Spring Festival, the weather will start to get warmer, so you can pilling.

Then change the soil, add fertilizer,

Buds will appear around March,

It will bloom around April.