for the seed to pop when it is about to sprout (see Molina)
Alonso de Molina:
yollotlatzini. ni . (pret. oyollotlatzin.) rebentar la semilla quando quiere brotar. Alonso de Molina, Vocabulario en lengua castellana y mexicana y mexicana y castellana, 1571, part 2, Nahuatl to Spanish, f. 41r. col. 1. Thanks to Joe Campbell for providing the transcription.