I was surprised and then horrified to discover while doing some investigation that Basil would kill Rosemary. If this was true, I surely did not want to put them in the same bed together!
Don’t worry. This is not a start of a bad novel. Having five table-high raised beds filled with vegetables, I wanted to plan the proper locations for companion herbs so that each would get all the help possible from the onslaught of insects – either by repelling the “bad guys” or by attracting the ‘beneficials’ that will eat the “bad guys”. The problem was figuring out which herbs and vegetables are friends and which are enemies. It isn’t all that easy. If you do a google about companion gardening, you will find conflicting information.
Take this example of basil killing rosemary. Where did this come from? I had never heard this before – I surely would have remembered learning this when I was in school! – and I have seen many beautiful herb gardens where rosemary and basil were next to each other. Yet here was this Wikipedia article claiming that basil would kill rosemary. So I googled basil kill rosemary and several sites did come up. But I found that everyone of them had a companion plant list that was exactly the same including the phrase basil will kill your rosemary, even to having the parentheses. What seems strange (perhaps a better word would be suspicious) is that the phrase is the only phrase in the whole list with a personal reference – (basil will kill your rosemary).
Checking other sites that had this phrase but without the list, I discovered that they are forums, blogs and discussion groups where a member states that they read that basil kills rosemary and therefore are changing their garden plans accordingly. All these entries are dated in May 2011. Interestingly, the Wikipedia article was last modified 9 May 2011!
So to continue my validity check of this article, I searched a fairly large sample of companion garden lists published at government and organization web sites, such as, state agricultural sites and garden organizations. I could not find a single reference to basil and rosemary being incompatible, much less basil killing rosemary.
Looking at the references listed in the Wikipedia article, I decided to check the web site references, Surprise! Not a single one had basil being incompatible with rosemary. In fact each one only listed incompatibility with rue – which is exactly what I had learned in school years ago. So this addition of sage being incompatible is also suspect. And the books that were listed as references? They were the same books that were listed on the referenced sites that did not have basil incompatible with rosemary or sage. Looking at the dates of the books (1974 and 1998), we surely would have heard about these incompatibilities before this article was written. So overall, the credibility of this article is totally suspect. (Update 6/5/2011: I removed the counter-factual items about basil, rosemary and sage from the Wikipedia page).
The reference lists given in the article are not copies of each other, but the information is consistent. So I will use these lists as a reference for my own garden, as well as other resources I have (like my text books and gardening books).
So, as I have discovered many times with other topics, information on the internet is not necessarily valid – even in Wikipedia. Sources need to be checked thoroughly.
As for placement of basil, rosemary and sage. I do have them sharing a bed.