During the weeks of back-to-school time in the late summer and early fall, which coincides conveniently with the beginning of cold and flu season, dark violet-toned elderberries grow plump and ripe on their thick stems, drooping low to the ground and begging to be plucked. In keeping with the season, elderberry is a star student and makes an A+ antiviral plant. Acting as both preventative and treatment, these tiny but potent purple beads of healing ward off viruses whether they are in the environment or have already taken hold within the body. Keeping a massive range of different viruses at bay is what elderberry does best, and it has been respected for centuries for this specific use.