Mat 13:32 Which indeed is the least of all seeds: but when it is grown, it is the greatest among herbs, and becomes a tree, so that the birds of the air come and lodge in the branches of it.

The tree growing from the seed and bearing fruit is one of the key symbols Christ uses to describe the the cycle of tranformation. The focus here is that a little bit of spirit can grow something very large and valuable. The complete cycle is seed to earth to tree to fruit to seed again, It represents the pattern of spirit creating relationships shaping mind choosing action (body) contributing to spirit again. Here the cycle is mustard seed to field to tree to branches to birds of the air, but all of the elements are there with the branches taking the place of fruit as the body and the birds symbolizing the spirit.

My version: That is truly the smallest of all seeds: but when it is grows up, it is the biggest of clutivated plants, and becomes a tree, so that the heaven's winged ones arrive and settle in its branches.

"Grows" is from auxanô, which means "to gow large," "to increase in power," and "to grow up."

A new term here is lachanon, which is translated as "herbs" but which generally means "garden plants" as an opposite of wild plants.

The word translated as "lodge" is kataskênoô, which means "to camp" and "to take up quarters" but specifically means "to settle" when applied to birds.