I've been a raised bed gardener for a long time, but this was my first year at seriously growing onions. I just harvested the crop and noticed that most of the onions that were next to my border of 2x10's were much smaller than the ones that grew toward the middle of the bed. I've never had that happen before with any crop, including garlic. Is there something unique to onions that would cause this?? It may be hotter, drier, etc next to the wood but I'd be curious to know if anyone else has observed this.