This is not surprising at all. By far, the greatest percentage of a deer's diet is native foods. Different plants peak at different times, and deer seek out what they need when they need it. I've gone through a similar journey to you. The next step for me is weed management. Watch the video at the beginning of this thread:
Weed Management Thread. From my perspective, there are two major roles for food plots, attraction for hunting, and/or improving the local herd (QDM). For attraction, the key is choosing crops that peak and are attractive to deer at the specific seasons you plan to hunt. For QDM, the key is choosing crops that provide quality food when nature is stingy with food. They even out the valleys where deer are stressed. Depending on location this could be winter, summer, or both.
Important factors for me have been:
- Avoiding deep and frequent tillage that destroys OM and soil tilth.
- Planting crops that both feed deer and improve soil quality and OM.
- Ignoring yield on a per acre basis and planting more acreage if necessary.
- Becoming much more weed tolerant.
- And lately, managing weeds as food for deer.
Like you, I've had quite a journey and changed my approach as I learned. I have not used commercial fertilizer in years. My costs are way down and my results are as good or better than they've ever been.
"too soon old, too late smart"
