Any ideas for keeping a gravel "potty area" less stinky in the hotter weather?

Vinegar should do it, non-toxic, enviromentally safe and cheap. I'd mix it about 50/50 with water and use a garden sprayer to spray the area. I used it in my car to get rid of the smoke smell and it's the only thing that worked!

There are a lot of dog safe cleaners that carry enzymes that break down the mess and also will kill the smell. I have heard of one called Consume (not sure if that is the proper spelling) and it is a green liquid that you spray down to kill the odor. Enzymes work best to cut out the smell and keep the area sanitary.

White Vinegar, it will also kill any weeds popping up & it is safe, yes, you will smell the vinegar but it fades and it doesn't smell as bad as what you clean up, it is also a disinfectant, I use it mixed with baking soda to keep my drains without odor & germ free also in my dark wash, not as disinfecting as bleach but allot safer, if you try it let us know if it worked for you.

Try different food, look for something with less fillers like Science Diet or my favorite Solid Gold. Food really does affect the odor of the stool.

Mix some water and vinegar and give it a good rinse down. There are some products that also helps with smells for yards, they hook onto your house and your spray them (usually on grass). They have a perfume smell, but work alright.

Try Borax