What affects berry yield on BDSP?

Question

I planted the 5 confusion inducing recovery berries. According to Bulbapedia, they return 2-5 berries each, but there is no other information. My berry bushes returned either 3 or 4 berries (including the same berry) without me doing anything different. Are there some mechanics here I'm unaware of, or is it just random, like the 2-5 hit moves (e.g. pin missile)?

Comments

Serebii says that due to a lack of mulch in these games, you can't do anything to increase yields. Bulbapedia says BSDP berry mechanics are still unclear.

https://serebii.net/brilliantdiamondshiningpearl/berrygrowing.shtml
https://bulbapedia.bulbagarden.net/wiki/Berry#Generation_VIII