Companion planting that actually works in tunnels

I plant basil between my tomato rows in the tunnels. The basil repels whitefly and aphids — I haven't sprayed in 2 seasons. The trick is to plant the basil 2 weeks before the tomatoes so it's established. Also works outside: marigolds around your pepper beds keep nematodes away. Not all companion planting is proven, but these two are real for me.