Macadamia as an Alternative Crop for Florida
Florida growers are constantly looking for alternative crops to diversity, and find new markets; however, that hunt is becoming more intense. A promising new central Florida crop in production includes Macadamia which has found success in south and central Florida.
Hawaii leads the nation of Macadamia production by 18,000 acres in 2017 and crop worth estimated at $42 million. California and Florida grow macadamias on a small scale. Overall, the United States ranks #2 in world production of macadamia behind Australia where the nut originated. Latin America, South Africa and Asia are other key producers that have entered the market and have found economic success. These rather hardy trees, tolerate temperatures as low as 24 degrees. Macadamias require at least four to five years before the trees begin to produce nuts and six years before the trees are in full production.Commercial macadamia nut orchards are planted with grafted seedlings. Trees are likely to bear a small crop in the fifth year after planting and will reach full production in 12 to 15 years. A good tree in good health can produce macadamia nuts for 40 years.
Trees prefer deep, well-drained soils that have a pH of 5.0 to 6.5, and require 60-120 inches of rainfall per year. They can be grown from sea level to an elevation of 2,500 feet. Due to low nut yields and harvesting expenses it requires a major capital investment.
The trees prefer subtropical climates, however, high humidity can increase the risk of blossom blights. Temperatures should not fall below 33°F or regularly rise above 95°F, since the low temperatures increase the risk of damage while the high temperatures reduce vegetative growth, increases premature nut drop, decreases nut growth and oil accumulation, and may cause leaf burn.
Mature trees are extending and can reach tall heights of 60 feet. They also are susceptible to many pests and diseases and need a lot of management for profit and good nut quality. Trees are spaced at 23 ft x 13 ft (or 125 trees/acre) at maturity, nut yields peak at 150 lbs of in-shell nuts/tree.
Florida production season runs from July through November. However, little information is available on recommended cultivars and rootstock. It is advised that planting at least two varieties within the grove blocks of macadamia trees improves yield through cross-pollination.
Although the tree is highly resistant to drought; supplemental irrigation is vital during flowering and fruit set in spring/summer months. Severe drought will result in significant nut drop.
Trees are pruned to a central leader with suckers and excessive lateral branches removed for a stronger shape allowing wind movement within the canopy. Painting exposed trunks with white water based paint helps to reduce risk of sunburn and heat stress.
Field soil conditions mandate good drainage. Monitor phosphorous in the orchard with yearly soil tests. Use a well-balanced fertilizer when the trees are young for best results. South Florida and coastal areas with calcareous soils tend to suffer from zinc, manganese, and iron deficiencies.
Despite the relative uncertainty of this crop, it looks hopeful as a new alternative crop for Florida growers. Macadamia nuts garner premium prices as the demand surpasses current production. For more information on Macadamia in Florida click on the UF link: http://ufdc.ufl.edu/IR00003392/00001