So I've done myself a guide... if you're interested you can download a copy. The link is under Welcome! on the top right hand of my web site below. When the link opens click the item above 'Add a description' to download.

Hope it helps... & if you think there's anything missing please let me know!

Thanks, John

The area of 'why' is a wonderful addition but still ventures into the folklore perception. Most of the on-line charts show the why. There are a few sites that offer plants in answer to a problem. The latter sources are likely how you generated your chart and the effort is appreciated.

The companion plant relationships are one area of personal study. My goal is finding actual facts offering the biological, chemical and/or ecological contribution. Some of the obvious are know symbiotics.

I have posted a few links in Organic and Vegetable topics that have been looked at. It is very hard to locate specific relationship studies and suppose that there are few actual such studies.

One item of note is the marigold action against nematodes. In report I have view they credit the exudates but after residue is incorporated and decomposing. The effect is generally of advantage in the following year of the incorporation. Food for thought and example of the information I hope to provide in such a chart.

Good effort. Thanks.