Mat 15:13 Every plant, which my heavenly Father has not planted, shall be uprooted.

Plants are Christ's symbol for productive work of the mind, but here what is really being discussed is not plants, but planting a metaphor that brings together "the spiritual," in the form of the seed, "the emotional relationships," in the form of placing seeds in the earth, and the mental, in the form of a plant arising from knowing how to put the seed in the earth. Christ is saying that the works of men that are not consistent with the will of God are temporary, doomed to eventually fail.

Alternative translation: Every planting that my heavenly Father has not planted will be rooted out.

Symbolic version: Every generation of effort that is not based on the work of God is a total loss.

"Plant" is from phuteia, which doesn't mean "a plant" (except as translated here) but "planting," "generation," and "production." It has the sense of one crop in a cycle of crops, one harvest in a cycle of harvests. The verb phuteuô, "to plant" is used for "planted." "Uprooted" is from ekrizoô, "rooted out."