So for the last few years we have been companion planting our annuals when we noticed something. For one reason or another, the yields were always better when we planted only two varieties than when we tried to do three or more. I would try growing tomatoes, carrots, and basil and they never really did much until I dropped the basil one year and BAM - tomatoes and carrots like we had never had at our property. The same was true for our three sisters garden, this year we did not bother to put much effort into the cucurbits (which never do much due to squash bugs) and we have had our best corn and bean harvest to date at the property. We didn't even try a third companion for our potatoes and peas and you would think that our soil had magic powers based on how well they did.
I am starting to think that when time and resources are limited and you are looking for the biggest bang for your buck from annuals (i.e. canning 20 quarts of each variety) that it is better to focus on a "buddy system" than to go with a team of companions - anyone else experience this when trying to do polycultures?
Very good observations Thomas, part of the "three sisters" planting setup is that you bury fish first, build a mound over the fish (one for each plant your going to put in right away which is the corn), then you plant in succession, so each comes up at the right time for it.
Many of the people I know who have tried the method plant all the seeds at the same time, this can create problems since the corn, beans and squash all compete for water, nutrients and sunlight at the same time. That is not how companion planting was carried out by the people.
We would plant the corn, it would come up and start growing, once it was about a foot tall we would plant the beans close to the corn stalks.
When the beans were starting to twine around the corn stalks we would plant the squash seeds further out so everything had space to grow as it wanted to grow.
There is not problem at all with only having pairs if that is what works best for you, then that is the way your land wants to be planted.
Squash bugs are a problem and they will attack plants that are not in the family. To get their numbers down you can remove the leaves with eggs and burn them, you can pick the bugs and drown them in soapy water and you can turn the soil in mid winter to get a kill on the hibernating adults.
Changing where you plant each year can help but we have found that the adults just seem to be able to locate the new area, so we do all of the above methods to reduce their numbers.
I'm still looking for the right predators, chickens seem to be a pretty good predator but they tend to decimate the plant at the same time.