You shall not sow your vineyard with two kinds of seed, lest the whole yield be forfeited…
#deuteronomy 22:9-12 #kitetse
Does this passage forbid companion planting? Yes, if broadcasting, but probably not if done in rows, regular patterns, etc. This law forbids broadcast sowing different seeds in a vineyard. Leviticus 19:19 forbids it outside a vineyard.
Although #torah rules against mixing things are meant literally, the principles apply more broadly. Yoking an ox and a donkey together is cruel to both. But this extends to agriculture, marriage, business, and more.
This isn't about maintaining absolute purity in every way. For example, you don't need racial or ideological purity when looking for a spouse, but don't even consider marrying an unbeliever. Do not be unequally yoked together with unbelievers.