笼 has two readings: lóng (cage, basket) and lǒng (to envelop, to cover, as in 笼罩 lǒngzhào). As a standalone noun meaning cage/basket, it's always lóng.
culture
笼 as a steamer basket is central to dim sum culture. 小笼包 (xiǎolóngbāo, soup dumplings) literally means 'small steamer-basket buns.'