Pilosocereus pachycladus
Native range: Brazil
Known names: Blue Torch Cactus, Fuzzy Blue Torch Cactus
Hardiness: Best kept above 40º
Mature Size: 20'+ in the wild...but much much smaller in pots. 
Light: Best in full sun.
Water: Can take dryer conditions but grows faster with regular watering in summer. Keep dryer in winter
Soil: Succulent mix
Dormancy Period: Winter
Pet-Safe: No
Plant Size: Grown in 2.5" pot
 
This is considered one of the bluest cactus. Fuzzy spines lining the ridge. Very eye-catching!