The Literal Commandment
The literal commandment: "You shall not sow your vineyard with two kinds of seed, or all the produce of the seed which you have sown and the increase of the vineyard will become defiled." (Deuteronomy 22:9)
The literal commandment is that we are not to cow a vineyard with two kinds of seed. If we were to do so, the produce of the seed and the vineyard would become defiled.