Bring 2 cups water to a boil. Add tea bags and herbs. Remove from heat and let stand for 10 minutes. Strain through a fine sieve; discard solids.
Sprinkle gelatin over remaining 1/4 cup water, and let stand until softened, about 5 minutes. Bring 1/2 cup tea mixture to a simmer in a small saucepan over medium heat. Add sugar, then softened gelatin, stirring, until dissolved. Strain through sieve into remaining tea mixture.
Pour mixture into a 5-by-9-inch loaf pan. Refrigerate until set, 4 hours or up to overnight. Cut into 1-inch cubes and carefully lift out.