An "Indigo strain" refers to various cannabis strains with "Indigo" in their name, often indica-dominant hybrids known for relaxing, euphoric effects and fruity/earthy flavors, like Indigo Berry Kush or Indigo Sapphire, though there's also a non-cannabis Indigo grain variety. Specific strains like Indigo Sapphire offer high THC (around 33.8%) and a mix of indica/sativa traits, providing creativity and deep relaxation with grape/mint notes, while Indigo Berry Kush (50/50 hybrid) offers classic Kush scents with sweet, spicy, and fruity undertones.