I love macadamia nuts. Yesterday, we visited the Mauna Loa Macadamia Nut Company grove, processing plant and visitors center.

Hawaii grows 90% of the world’s macadamia nuts and nearly all of them are grown here on the Big Island, with Mauna Loa Macadamia Nut Company (now owned by Hershey) being the largest producer. So, we were at the center of the macadamia universe, so to speak.

The macadamia is actually indigenous to Australia. In 1882, the tree was brought to Hawaii to use as a windbreak and as an ornamental. It was 40 years before it was recognized as a potential food crop.

The first macadamia plantation in Hawaii was started in 1921. It wasn’t until the 1950s that macadamias were really grown commercially here, but by the 1970s, as sugarcane production waned, macadamia farming really took off.

It takes the tree 7 years to start producing, but once it starts it can be harvested for over 100 years. The Mauna Loa Company now has 250,000 trees and is the biggest producer of macadamias in the world.

The nut grows on the tree, encased in a husk and very hard shell.

Eventually, the nut ripens and falls to the ground.

On the ground, the husk may fall off, leaving the nut within its shell.

The nuts are not picked from the trees; they are harvested from the ground, usually by machine, but also by hand in areas that are too rugged for the machines to manage.

Once harvested, the nuts are placed in storage compartments for about 10 days to dry, at which time the nuts become detached from their shells. But the shells are extremely hard and it takes pressure of 300 pounds per square inch to break them open. The Mauna Loa Company has mechanized this part of the process, using opposing geared crushing wheels with just enough space left between them for the nut to escape unharmed while the shell is cracked and crushed.

The discarded husks are collected and whisked away to be burned to generate electricity that is used at the processing plant. You can see the dryers, storage tanks and discarded husks in this photo.

The nuts are then processed in this facility:

The Mauna Loa Company produces 8,000,000 pounds of finished macadamia nuts each year. Most of the production line was closed when we visited (it’s growing season right now, not time for harvest), but they were still running parts of the line that are used to make chocolate covered macadamia nuts (remember, the company is now owned by Hershey).

We bought a couple packs of processed, salted macadamia nuts at the visitors center before leaving, but I doubt any of them will make it back to the mainland; they’re just too good and I’m addicted.

Sometimes you just feel like a nut.