Companion planting is the concept of grouping together mutually beneficial crops.
The point of companion planting is to create a community of plants that help each other.
Companion planting isn’t necessarily a beginner’s technique. To get the most from it, you need to be fairly knowledgeable about crops.
Interplanting is a useful way to save space. If you can fit several different crops in the same pot, why wouldn’t you? However, cramming something like potatoes and carrots into a 10-gallon pot and leaving it be won’t work.
Equally, not all companion plants need to live in the same soil. If you’re using crops to deter pests or attract pollinators, keeping them nearby will be enough.