• Higher elevation—we’re about 1,000 feet (300 m) higher than Fresno where we bought the tree
• Higher latitude—we’re at a position that’s directly east of San Jose where growth is rampant
• Gentle loving care—not some slave’s dull boring job
• Deep-well water—pumped by nice clean solar power, too
• Alien super-growth vitamins shot from a passing saucer craft on a moonless night
I like the last one. Besides, it sounds more plausible than any of the rest.