This rare kanji has no clear standalone meaning. Treat its meaning as uncertain.
稴 combines 禾 (grain) with 兼, which likely contributes a phonetic element. The exact historical development is uncertain.
The left side 禾 suggests grain or rice, and the right side 兼 suggests combining. Imagine a rare type of grain that is combined with other crops, but its exact meaning is unclear.
For レン, picture a lens (レン) focusing on a rare grain plant: lens -> レン, and the grain is 稴.