A Chilan Berry will mature from a planted seed to a full-grown, fruit-bearing tree in 72 hours, with 18 hours per stage. A Chilan tree will yield 1-5 Berries.
Generation VI
A Chilan Berry will mature from a planted seed to a full-grown, fruit-bearing tree in 48 hours, with 8 hours per stage. A Chilan tree will yield 3-20 Berries. During its growth, watering the plant will add 1 Berry to the final harvest, weeding it will add 0.5, and removing a pest will add 2.
Poffin cooking
At 100% performance, this Berry can produce a Level 20 (maybe higher) Dry-sweet Poffin.
Unlike the other Berries in this series, the Chilan Berry simply weakens any kind of attack of its type. This is because there is no type that takes super effective damage from Normal attacks.
When buying Chilan Berries in Join Avenue, the text will say "A set of four Chilan Berries. They weaken a supereffective Normal-type attack against the holding Pokémon." This is most likely a mistake since all other damage-reducing Berries only work if the attack is super-effective.