This is Luanne. Luanne is a Norfolk Island Pine that I bought from a plant nursery in Connecticut about 15 years ago. She was maybe a foot tall when I brought her home - and she was just known as "the tree." Then a couple years later I met R, who has a tendency to name just about everything that holds still - so she became Luanne.
Luanne now stands over 6 feet tall - and several folks who have come to our house (she stands just inside the front door) have commented something to the effect of "wow - you must use a lot of Miracle Gro!"
Happy to say, Miracle Gro has never been part of Luanne's diet. Instead (and in addition to occasional top-dressings of worm compost) we feed her (and all our other house plants) water from our fish tank.
About once each month, we change out about 1/3 of the water in our fresh-water fish tank. Instead of dumping the nutrient-rich water, we take buckets of it around the house and make sure each plant gets some. From what I've read, fish water typically has lots of nitrogen, which makes plants happy. If Luanne is any example, I'd even say "super happy!!" If you have a fresh-water tank, and you have house plants, give it a try - it really works!