Pilosocereus Cactus Mix Perfect for Greenhouse or indoors!! GORGEOUS BLUE Cactus Mix. Keep in direct sunlight when grown to keep the blue color vibrant, otherwise it will turn greenish. Needs full sun to keep the beautiful blue color ! Sowing instructions: Sow in trays, pots using any cactus mix (mixed with 50% sand works wonder for us) in a warm location to maintain an optimum fluctuating temperature of 65 (night) -80F (day) in light but not direct sunny spot. Often slow to germinate; takes anywhere from 3-15 weeks. Once established they require very little if any care at all.