Macadamia nuts have a very hard shell, which is difficult to break with a standard nutcracker. A small quantity of nuts can be cracked with a vice. For a larger quantity it is easier to use a special nutcracker designed for macadamia nuts. One retail source is the Gold Crown Macadamia Association in Fallbrook, Phone 760.745.4396 or www.macnuts.org .
By V. Lazaneo, Urban Horticulture Advisor, Emeritus UC Cooperative Extension, September 2012