ripen

to grow ripe; to become mature (said of grain, fruit, flowers etc.)

Grapes ripen in the sun.

[…] the desert soil of the Great Basin is as rich in the elements that in rainy regions rise and ripen into food as that of any other State in the Union.

To approach or come to perfection.

The acquaintance soon ripened into a warm attachment.

To cause (something) to mature; to make ripe

The warm sun ripened the corn.

To mature; to fit or prepare; to bring to perfection

ripen the judgment

When Faith and Love which parted from thee never Had ripen'd thy just soul to dwell with God