PES

*fkḥ - to become bright, to be ripe, to be happy (EDA 267)

Probably compare with Akk. nepelkû, napalkû ‘to be wide’. 

Geez
fakḥa - to be happy, to rejoice (CDG 158)
Amharic
fäkka - to burst open, to bloom, to be ripe (AED 2327)
Harari
fäkäḥa - to become bright, to bloom (EDH 62)