Thursday, August 28, 2008

The information and photos on this page are from the published files of Scot. C. Nelson, Ph.D., Associate Specialist (Plant Pathology) University of Hawaii at Manoa.

The University’s educational website about noni (Morinda citrifolia) is provided by the University of Hawaii at Manoa, College of Tropical Agriculture and Human Resources.

When do young noni plants begin to bear fruit? Noni plants can begin to bear fruit about 9 months to 1 year after planting. Fruits can be harvested at this early stage, although they are generally small and few. Some farmers choose to forgo harvest during the first or second years in favor of pruning back the branches instead.
Under favorable growing conditions, noni plants may begin to produce small flowers and fruits about 9 months to 1 year of age.
When during the year can noni fruits be harvested? In Hawaii, noni fruits are harvested year round, although there are seasonal trends in the amount of flowering and fruit production that may be affected or modified by the weather and by fertilizer and irrigation. Fruit production may diminish somewhat during the winter months in Hawaii. A given noni field is usually harvested from 2-3 times per month.
What are the expected yields for noni plants? The following estimates for the potential yield of noni plants are based on a series of assumptions. Please be aware that many factors may diminish yields. Nonetheless, the following estimates are achievable with good farm management and excellent growing conditions.
Yield assumptions: Plant population: 290 plants per acre; good soil fertility and drainage; good water supply; adequate disease, pest and weed control; adequate fertilizer plan (e.g., 6 lbs of 10-20-20 per plant per year).
Month Expected Fruit Yield* 0-9 Seedlings grown in nursery, no fruit production 9 Transplant into field, no fruit production 12-24 (year 1) 2 lbs fruit per plant per month (i.e., 24 lbs per plant per year 1) 24-36 (year 2) 4 lbs fruit per plant per month (i.e., 48 lbs per plant per year 2) 36-48 (year 3) 8 lbs fruit per plant per month (i.e., 96 lbs per plant per year 3) 48-60 (year 4) 15 lbs fruit per plant per month (i.e., 180 lbs per plant per year 4) 60-72 (year 5) 20 lbs fruit per plant per month (i.e., 240 lbs per plant per year 5)
*Realistic estimates based on excellent farm management practices and growing conditions. Actual yields may vary. Therefore, based on this model, at year 5 a farmer can expect to harvest approximately 69,600 lbs of fruit per year per acre, yielding about 35,000 lbs of juice (at an extraction efficiency of approximately 50% by weight). The juice weighs about 9 pounds per gallon, so an acre of well-managed noni can produce approximately 3,800 gallons of juice per year. For mature trees or farms older than 5 years, yields of up to 500 lbs of noni fruit per plant per year may be realized. However, many factors can impinge on these numbers. Most farmers do not realize the attainable yields due to pest and diseases or poor agronomic practices. On average, one might expect the average farmer to realize yields significantly less than 50,000 pounds of fruit per acre per year.
At what stage of development are noni fruits picked? Noni fruits can be picked at any stage of development, depending on the intended processing method. Some producers prefer green fruits, whereas other processors prefer the hard white noni fruits for processing. Most noni juice processors accept or prefer the “hard white” stage of fruit development for noni juice production, because the fruits ripen quickly once that stage of development is reached.
Noni fruits in various stages of development, from flowering (foreground) to “hard white” (background). Noni fruits may be picked at any stage of development, depending on the intended product or processing operation. The “hard white” fruits are usually picked for processing of the traditional noni juice beverages.	Translucent noni fruit, 1-2 days after harvest of the “hard white” stage. The translucent fruits are ready to release their juice.
How are noni fruits harvested and handled? Noni fruits are harvested by hand by picking the individual fruits from the branches. They are placed in baskets or bags or placed in bins for transport to the processing facility. Noni fruits do not bruise or damage easily, and usually no special padded containers or other precautions are needed to prevent fruit significant fruit damage. Furthermore, exposure of noni fruits to direct sunlight or to warm temperatures immediately after harvest is not a significant concern. So, noni fruits need not be refrigerated after harvest and are usually not refrigerated.
How are noni fruits handled at the processing facility? Fruits are washed at the processing facility before they ripen fully and turn soft. For juice production, the noni fruits are held at ambient or room temperature for 1 to several days to ripen before they are processed. However, prompt processing for juice is important, for if ripe fruits are allowed to sit for an extended period, they begin attract unwanted fruit flies, rats and other insects or pests. For processing of noni fruits for powders or other precuts, the fruits may be processed immediately, before they fully ripen. Unripe fruits are easier to work with some types of chopping and drying equipment.
Hard white noni fruits arrive at a processing facility in an onion bag.