Lemonade is a pretty simple recipe. Lemons, sugar, water and stir. Because of it's simplicity, I suggest you use the best fruit possible: organic for sure, biodynamic if you can find it.
We'll begin with the simple syrup because it will need to cool. Slice up those 5 jalapeno peppers and add them, seeds and all, to a small sauce pan. Add in 3 cups of sugar and only 2 cups of the water. Warm the mixture over a low heat but once the sugar begins to dissolve, turn it up to medium-high. When it just begins to simmer, remove it from the heat and let it steep for about 5 minutes. Then strain out the jalapenos and let the syrup cool. NOTE: Syrup in this fashion is usually referred to as a rich syrup. The only difference between a rich syrup and a simple syrup is that simple syrup is a 1:1 ratio and rich syrup uses more sugar.
In a large pitcher, juice the 8 lemons and 8 limes, add in the remaining 3 cups of water and sweeten to taste with the syrup. Serve over ice and garnish with citrus and jalapeno slices.