Mammillaria spinosissima 'Compacta' - One Off SpecialsMammillaria spinosissima, also listed under the synonym Mammillaria pico, is a striking cactus native to central Mexico, where it thrives in arid, rocky slopes. The 'Compacta' form is highly sought after for its tightly packed, upright stems and especially dense spination. These exceptional, large specimen plants are rare, and only three are available. Care Tips Light: Prefers full sun to very bright indirect light for compact growth and flowering.