Macadamia: Hard to Crack, Easy to Grow
When you think of macadamia nuts you probably associate them with delicious flavor, high prices and Hawaii.
Actually the macadamia tree originated in Australia, but it is possible to grow these expensive nuts in many areas of Southern California.
According to Onnolee Elliott, an Orange County gardener who specializes in growing subtropical fruit and nut trees, macadamia nut trees will grow and produce well in Southland areas where avocado trees do well. Elliott, and her mother, descendants of pioneer Southern California farming families, live on a 1 1/2-acre mini-farm. There Elliott tends 30 macadamia trees that produce hundreds of pounds of nuts.
Elliott says the macadamia nut tree is a handsome, clean evergreen tree with superb ornamental value. It has glossy green foliage and clusters of pretty white to pink blossoms that are pollinated by bees and other insects. The tree will reach a height of 30 feet and spread 15 to 20 feet. The macadamia is a long-lived tree that begins nut production five to seven years after planting. Depending upon variety, nuts reach harvest stage from fall through late winter.
Elliott has four named-variety macadamia trees and several volunteers in her orchard. One variety, simply called No. 246, was bred at the University of Hawaii and performs particularly well in her orchard bearing huge quantities of nuts. Another, called No. 333, is two or three weeks earlier than most varieties with a harvest that usually begins in early October. Two other varieties, called Burdick and Elimbah, are supposed to be softer shelled and easier to crack than other varieties, but Elliott says this isn’t always the case. And being easy to crack is not a virtue of most macadamia nuts.
For home gardeners, once they get the trees established and bring them to the harvest stage, the really tough job is cracking the nuts. Without a doubt, macadamias have the hardest shells of any nuts. After you’ve bounced a hammer off them a few times and smashed your fingers, you’ll try a different approach.
According to Elliott, for the home gardener with only one or two trees, the best bet is a hand nut cracker. Special macadamia nut crackers can be purchased from the Gold Crown Macadamia Assn., P.O. Box 235, Fallbrook, Calif., 92088, phone (619) 728-4532. Since Elliott has 30 trees, and sells the nuts, she uses a mechanical macadamia cracker that cost her several thousand dollars and is the same type used by commercial growers in Hawaii.
Elliott cautions that when harvesting macadamia nuts, you should never pick them from the tree. The nuts, which grow in clusters like grapes, fall to the ground of their own accord when they are ripe.
After the nuts fall, Elliott says you should remove the husks, which are similar to walnut husks, and then dry the nuts in the sun. She recommends that the nuts be sun-dried for three or four weeks. She says that during the drying process the nuts must be covered at night to keep the dew off them or they won’t cure properly.
After they are dried, the nuts are delicious raw or they may be roasted and salted. Elliott recommends storing the nuts in the refrigerator or freezer; this will keep them from becoming rancid.
Macadamia nut trees are becoming more available in local nurseries, however you may have to phone around to locate a tree.
Macadamia trees make best growth in a good, deep, well-draining soil. The planting site should be an area that receives full sun. Allow for 20- by 20-foot spacing when selecting your planting area.
When planting, dig a hole twice as wide as the root system, but only as deep as the tree was originally grown. Test the soil for proper drainage by filling the planting hole with water. Let the water completely drain and then fill it again. If the water does not drain out within 12 hours, choose another planting site or refer to a soil guide for correction methods. Improper drainage is a danger to young trees. After testing, place the tree in the planting hole and refill the hole with the soil you originally removed.
Planting time is a good time to add slow-release fertilizer tablets. Such tablets will provide long-term nutrient release without burning the roots. They are also ideal for fertilizing established trees. Follow label directions carefully.
If using another type of fertilizer, make only a light application, as the trees are quite susceptible to fertilizer burn. Don’t fertilize new trees with anything other than slow-release fertilizer tablets. To assure the roots moisture, water during the planting process.
After planting, if there is no rain, water the new tree two times a week, or daily during Santa Ana winds or hot spells, for the first six weeks. Then establish a weekly (in the absence of rain) watering routine. A deep watering is necessary, however avoid soaking the lower trunk area for an extended period of time. This can be accomplished by trickle irrigation.
If planted during the winter, new trees should receive frost protection during nights when freezing temperatures are expected. Trees can be tented with a sheet laid over a frame of stakes surrounding the tree. Remove the cover promptly in the morning.
Unlike some nut trees, macadamia trees have perfect flowers, and a single tree will produce nuts without another tree close by to act as a pollinizer.
