There is a lot to be gained for the organic grower from companion planting which is basically planting something with something else as either a sacrificial crop or as a deterrent to insects or as an attractor for predatory (good) insects.
For instance growing nasturtiums alongside brassicas, the insects that attack should go for the nasturtiums meaning the majority of the brassica plants are unscathed. In fact nasturtiums are a good companion to lots of plants including:-
- all brassicas
marigolds are good companion to quite a few plants including
Parsley is good to plant with Asparagus. Parsley is also good for planting with tomatoes as is Basil.
Borage is good for planting with strawberries.
Poached egg plant companion planting
I use poached egg plants solely for companion planting as they attract hover flies. Hover flies and their lava eat black fly so they are great to plant around anything likely to be set upon by black fly (runner beans, roses, dwarf beans etc.). More on companion planting with poached egg plants here.
So it is well worth planting a few flowers amongst your vegetables. It is also said that planting carrots with onions confuses the carrot fly but it didn’t work for me. As with all things it’s all about trial and error, see what works for you.