Answer: Based on your description I am not sure what happened, but I would expect there is a difference in the soil. You might troubleshoot by checking fertility, pH, and condition such as how deeply the soil has been loosened, if there are plenty of earthworms and other life in it, if there is a hard pan, a herbicide residue (mint can be difficult to eradicate) or some other unusual factor. Before you give up, you might try again after amending the soil based on some basic soil tests and after adding plenty of organic matter such as compost, well rotted stable manure and bedding, rotted leaves, and so on to try to buffer any adverse conditions. You might also try (if you have a strong back) double digging the area, or at least till it as deeply as possible. Your County Extension (459-6003) should be able to help you with the tests and interpreting the results and may also have some suggestions.
Q&A Library Searching Tips