it's a plant, don't know if you know it but it's a cheap and really healthy syrup (juice) source. right now it's elder blooming season so, here a recipe:
50 elder flowers
170 oz / 1.3 gallons of water
1 / 3 ounces of citric acid
10 pounds of sugar
A preservative (optional)
In the bowl where you have extracted elder flowers pour over the water, citric acid, and lemon (cut into slices). let stand for 24 hours. after 24 hours filter it, add sugar, mixing occasionally. again let it rest for 24 hours. Then, pour it (syrup) into bottles.
You can also add lemon when mixing the syrup with water for better taste.
btw, this is elder (it's also known as wild elder, not to get it confused with other elder types)
http://en.wikipedia.org/wiki/Sambucus_nigra#Culinary
it has very intensive flower scent, u'll probably smell it before you see it
it's grows in sunny spots on the edges of forests.