Did you add any other soils to mix with your preexisting soil?
Do you have any research on whether amending your soil with other soils that might hold water better would be beneficial?
It is important to do crop rotation, from what I've researched about organic farming.
I grew up on a suburban farm. 12 acres to be exact. We had a small barnyard area, and a small plot of land for veggies. The soil was very fine whitish sandy loam. When it was plowed, the deeper you plowed the more moisture it held, and the soil changed its color to a darker brownish color. It retained moisture really well and our garden produced great yields.
I think perhaps more research is needed and there are a lot of good ideas for you in this thread. I hope the best to you and your wonderful heirloom wheat.
I would love to try it, as I believe that I have or am developing a wheat intolerance. I haven't been diagnosed as I don't have the money for testing. However, I do know that I have developed an intolerance to peanuts and some varieties of corn. It causes my legs just below the knees to break out in a rash, sometimes this rash is tiny spots, other times it develops into a very large mass. It also causes swelling and pain. What really made me aware of this was I was eating Kashi cereal straight out of the box. I loved this cereal. Well after I figured out it was causing my legs to break out I had to give it up. So, I'm not sure what was in that brand of cereal that caused my reaction to it. 
I will send Love and Light to your farm. Farms are so very important in our lives and I appreciate your giving your time and energy to producing food for yourself and farm animal families. 
Keep us posted on your progress.
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