There are two main commercial types of plums: the European plum (Prunus domestica) and the Japanese plum (Prunus salicina), each having many varieties. The European varieties are mainly grown for processing into dried plums (also known as prunes), but are also grown for the fresh market. Japanese varieties are almost always grown strictly for the fresh market (University of California, 2015). Early settlers introduced the European plum to the United States, whereas Japanese plums were first brought to California in 1870 (Sunwest Fruit Company, 2014).
The marketing season for California plums is May 15 to Oct. 20t; for California prunes it is Aug. 20t to April 15t. The marketing season for plums and prunes for fresh use and canning from Idaho, Michigan, Oregon and Washington is from Aug. 15 to Oct. 15 (NASS, 2015).
Schools have been focusing on healthier options for their students, and thus they are buying more locally sourced food. Dried plums are a great option for foodservice operators to introduce into their schools. They can be pitted and eaten whole, or used to improve processed foods. Plum puree is a great substitute sweetener for reduced fat baked goods, and works great to improve flavor and retain moisture in pre-cooked meats. Food service operators and farmers can both benefit from this exchange by working through a government program called Farm to School (CDPB, 2015) (USDA, 2015).
Other means of adding value to fresh and dried plums could be selling them through farm stands, farmers’ markets, U-pick operations, and Community Supported Agriculture (CSA). CSAs truly allow the community to be involved in the farming experience. Members of the community buy a subscription in advance from the farmer to receive a share of the farm’s crop throughout the growing season. CSAs are unique because the members also share in the risks farmers face, such as poor harvests due to adverse weather or pests. Selling to the community in advance provides the farmer with the working capital needed to run the farm, gets the farmer better prices for their crop, and eliminates time and money otherwise spent on marketing avenues (NAL, 2014).
In 2016 the United States produced 135,000 tons of fresh plums from 18,700 acres. The total value of the crop was $109 million. The United States also produced 54,000 tons of prunes (dried plums) from 45,000 acres. The total value of the crop was $86 million (NASS, 2017).
Chile provides nearly all of the imported plums to the United States, accounting for 80 percent of the total. In the 2016/2017 market year, the United States imported $40 million worth of dried plums and $54 million worth of fresh plums. In 2016 the majority of plum imports entered the United States in February and March (ERS, 2017).
A characteristic of many stone fruits is alternate bearing (AB), meaning the plant will produce more fruit every other year. AB is internally regulated by the plant, but can be triggered by external factors such as poor management. The most successful practice to control AB is crop load management achieved by fruit thinning and pruning (Pennsylvania State University – Extension, 2011). Most fruit trees, including plum, also require chilling hours (close to freezing temperatures) to induce flowering. Generally, European plums require 700-1,000 chilling hours and Japanese plums require 500-900 chilling hours (UC IPM, 2014).
Helpful enterprise budgets for plums:
Alternate Bearing in Fruit Crops, Pennsylvania State University – Extension, 2011.
Community Supported Agriculture, National Agricultural Library, USDA, 2014.
Farm to School and Selling Local Foods to Schools – A Resource for Producers, Food and Nutrition Service, USDA, 2015.
Fruit and Tree Nut Data, Economic Research Service (ERS), USDA, 2015.
Management of Plums, - University of California Agriculture and Natural Resources Statewide Integrated Pest Management Program (UC IPM), 2014.
Plum Facts – Sunwest Fruit Company, 2014.
Plum and Prune, - University of California, 2015.
School Foodservice, California Dried Plums Board (CDPB), 2015.
Types of Plums, - Michigan Plums Growers Association, 2012.
Links Checked June 2018. .