Definitive companion planting sources

Hello Permies community, the more I research, I find more web sources that have turned anecdotal evidence into scientific databases for permaculture gardening. I'm looking for help in finding these sources because there are still way too many sources that tell you "plant this next to that" or "don't plant this near that" but I find no information as to why. An example would be, why do you keep cabbage family plants away from strawberries? Lot's of sites say don't do it but it's almost always a side note.

So here are my sources I have found so far and I hope we can all pool our resources together to make our permaculture gardens even stronger. Let's fill those niches!

Sites:
GH Organics companion planting:
http://www.ghorganics.com/page2.html

The Desert Echo: food forest gardens planting guide
http://www.thedesertecho.com/blog/food-forest-gardens-planting-guide/


Tell me your favorites and I can update this post.

I really enjoyed the book "Carrots Love Tomatoes"...even though it's not an online resource I think it's worth looking at if you find the time.

Thanks for starting a compilation, really just wanted to follow this post.

Hi, Brett! You're not the first to see the need for such a resource. The best compilation I know of is the Natural Capital Plant Database, http://www.permacultureplantdata.com , which makes an effort to document the published source of every claim it makes. However, that's not enough, because as you've found, many of the published sources don't provide sources for their own claims! Much of the data is anecdotal, and even when a thorough, scientific study shows that plants grow well together, there's rarely a mechanism proposed for how that relationship works.

For my money, I believe Dr. Elaine Ingham is closer to the truth with her research into soil microbes and microbiomes than any of the traditional research. Rather than plant A directly helping plant B and inhibiting plant C, it seems more likely that plant A is fostering a microbiome that is amenable to plant B and hostile to plant C. The research to prove such a causal connection will necessarily involve a lot of microscopes and a lot of patience, neither of which I personally have, and I think a lot of other permies are also lacking these resources.

So what we need is some kind of institute for permaculture soil research. Maybe it could be crowd funded and distribute its published results as a benefit to the donors. Maybe you could be the one to start it!

Thank you Colin and Ben! There are a couple of books that I have read which are amazing and that cite their sources. And that website you proposed was great but I see that they are falling into the problem many sites find themselves in and that's funding. Thankfully they have a free option but having to sign up seems very un-user friendly. Oh well, maybe I should start a new definitive database and searching system haha

Sites:
GH Organics companion planting:
http://www.ghorganics.com/page2.html

The Desert Echo: food forest gardens planting guide
http://www.thedesertecho.com/blog/food-forest-gardens-planting-guide/

The Natural Capital™ Plant Database
Http://www.permacultureplantdatabase.com/
(Requires membership, Thanks Ben!)

Brett,
The question of the Strawberry/Cabbage connection is one of soil pH. Brassicas prefer alkaline soil and strawberries like soil more acid. either one or the other will thrive depending on the pH. a good happy medium of 6.5-7.0 will be a middle ground for both to do well but neither will be exceptional.

Thank you, Michael. That makes sense. Do you happen to have any source for this info?

Sites:
GH Organics companion planting:
http://www.ghorganics.com/page2.html

The Desert Echo: food forest gardens planting guide
http://www.thedesertecho.com/blog/food-forest-gardens-planting-guide/

The Natural Capital™ Plant Database
Http://www.permacultureplantdatabase.com/
(Requires membership, Thanks Ben!)

Foraging Texas
http://www.foragingtexas.com/
(Great resource, even if it's only a log of the plants this gentleman encounters around Houston. Many of these plants can be found all over)

These are all great resources for getting started, but if we're honest there really is no pre-made resource for companion planting. We like to think that we can reduce agriculture to a science: "Plant these two things together and they will do well." And we can benefit from applying scientific principles in agriculture...but it is really more of an art - a poetry of the soil.

The exact same variety of plant situated on one side of an acre will behave differently from on the other side of the acre, because micro conditions differ. Likewise, what makes a good companion planting in one climate, soil, and other such conditions may be a terrible in other conditions. For every book or resource espousing never-fail companion planting charts, I've had someone who very successfully applies companion-planting principles tell me that the author is crazy and that combination never works for them.

While pre-made resources can indeed be a great place to start, there is no substitute for simply experimenting by planting various combinations of plants together on your own property and seeing what happens.

Hey James, thank you for the response! I know what you are saying but I'll have to disagree with your assessment that we can't reduce what happens in the soil, down to a science. Since science is nature and nature is science, what we do when we experiment and observe our environment is to practice the scientific method, even if we aren't publishing papers on the subject.
Now, anecdotal evidence is important because it gives hard science a place to start and we can all benefit from understanding the many interactions between soil microbes and the nutrient cycle. Considering the many factors in growing one plant, from sunlight to moisture and everything in between, it seems like a daunting task to collect and manage all of the reasons that a plant would behave in the way it does from one property to the next. However, we are already on our way to really having the details pinned down. Science isn't out to disprove anecdotal evidence, but merely to understand "why" and to weed out (no pun intended) misinformation.
In the case of the gardener who was able to successfully grow two plants together that shouldn't have thrived in close proximity, we need to understand what about their environmental factors made the plants thrive. By understanding the relationships, we can tailor our gardens to their maximum potential. Especially in the case of growing an integrated forest garden where all niche needs have been filled by the garden itself.
But that doesn't mean the relationships aren't poetically beautiful. I find loads of beauty in science. As an artist, the best garden designs aren't only functional, they are aesthetically pleasing and understanding the complexity of it is beautiful in its own respects.

I guess what I'm really trying to say is, since scientific literature is really starting to pin down the many factors and relationships, a definitive source for all of this combined information would be extremely helpful. Especially if it had a search function that allowed you to punch in your niche factors and then it would recommend plants, fungi, or lichen to place in the niche. Maybe someday

Brett Aldrich wrote:I guess what I'm really trying to say is, since scientific literature is really starting to pin down the many factors and relationships, a definitive source for all of this combined information would be extremely helpful. Especially if it had a search function that allowed you to punch in your niche factors and then it would recommend plants, fungi, or lichen to place in the niche. Maybe someday

I often dream about creating something akin to what you're saying. There are so many factors that can go into deciding what and where to plant and most online charts or lists can't handle it in full. I'm thinking a few drop down boxes could spit out some results the way mortgage calculators work online. May be a helpful, if not still limited tool.