Spinach

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Spinach (Spinacia oleracea) is a dark leafy green and flowering plant of the amaranth family along with beets, quinoa, and Swiss chard. Most believe it originated in Persia and was taken to neighboring nations throughout the empire’s existence, becoming very popular in Europe and belatedly, in North America by the early 1800s. Domestically, California and Arizona dominate U.S. production, with New Jersey and Texas also contributing to supply for the fresh market, though to a lesser degree. Fresh market consumption (in bunches, as well as chopped and bagged) continues to climb for this nutrient-packed leafy green, though spinach is still a popular vegetable for processed products.

Types & Varieties Spinach is classified as either smooth or flat leaf, savoy (crinkly), or red. Within these categories are hybrids like semi-savoy, as well as immaturely-harvested leaves known as baby spinach. Flat leaf is the most common type of spinach consumed in the United States with smooth, tender leaves, and is also used for canning and freezing. Savoy spinach, also called curly leaf, has a more bitter taste with deeply crinkled, crunchier leaves that can be rather difficult to clean. Semi-savoy has less crinkly leaves and is easier to clean than full savoy spinach, and is used for the fresh market, processing, and cooking. Red spinach leaves have the characteristic green coloring with a red center and round, tender, thick leaves and a sweet flavoring. Baby spinach is flat leaf and harvested before full maturity for increased tenderness, while baby spoon spinach is a type of savoy with a sweeter taste and tiny crispy leaves. Varieties of flat leaf include Corvair, Gazelle, Olympia, Pigeon, Red Kitten, Renegade, Seaside, Space, and Whale; for savoy there’s America, Ashley, Bloomsdale, Regiment, Samish, and Vienna; semi-savoy varieties include Acadia, Carmel, Catalina, Indian Summer, Melody, Reflect, Teton, and Tyee. CULTIVATION Spinach is a fast-growing plant that thrives in sandy, loamy soils (which have better drainage), and a pH of under 6.8. Mild temperatures and sun are ideal, though too much sun and hot temperatures will cause plants to bolt. As a cool season crop, however, spinach is hardy and can withstand frost and temperatures falling below 30°F. Drip irrigation is not recommended for high-density beds, sprinklers are a better fit to maintain moisture levels for shallow roots. Nitrogen is an important component to optimal growth, and as harvest approaches, weed control is a must.

Pests & Diseases Like other leafy greens, spinach is vulnerable to numerous pests, with cabbage loopers, leafminers, and aphids leading the fray. Others of note include beetles, grasshoppers, mites, nematodes, thrips, several types of worms, and whiteflies. Cabbage looper larvae will feed on outer leaves, leaving jagged holes on the way to the developing head. In similar fashion, leafminers make their way through foliage, leaving a trail of spots and laying eggs. Both pests can render plants unfit for sale or consumption. Green peach aphids go after the juice in leaves and transmit viruses that can stunt growth and cause browning, wilting, low yields, and eventual plant death. Common diseases include anthracnose, curly top virus, leaf spot, and tipburn. In addition, cucumber mosaic virus leads to a lack of coloring, curling leaves, and stunted growth. Damping-off can kill both seeds and seedlings and cause discoloration, stem rot, and death of the plant. Downy mildew is a threat at all stages of development, with yellowing and fungal growth on leaves. Lesions will develop and eventually turn brown. White rust appears as white bubbles on leaves, often with yellow spots. It can affect yields, appearance, and marketability. Storage & Packaging Spinach is highly perishable and prone to damage during harvest and packing. It should be hydro- or vacuum-cooled after harvest as warm temperatures can cause deterioration. Ice can be applied to reduce respiration and extend shelf life. Leaves are sensitive to ethylene and should be separated from any nearby producers. When stored at 32°F with high humidity (95 to 100%), spinach can retain its freshness for slightly more than 2 weeks. Resources: North Carolina State Extension, Rutgers New Jersey Agricultural Experiment Station, Texas Agri-Life Extension Service, University of California Vegetable Research & Information Center, University of Georgia, University of Massachusetts, Amherst. GRADES & GOOD ARRIVAL Spinach, whether bunched or as leaves, should be uniformly green, clean, and free from serious damage. For bunched spinach, roots should be trimmed. For spinach leaves, there are three grades: U.S. Extra No. 1, U.S. No. 1, and U.S. Commercial. All require leaves to be of similar varietal characteristics, well-trimmed, and free from coarse stalks, seed stems or buds, and damage (wilting, discoloration, disease, insects, etc.) Each grade may have no more than 1 percent of leaves affected by decay. For premium or U.S. Extra No. 1, in addition to the above, leaves must also be fairly clean and no more than 5 percent may deviate from requirements; for U.S. No. 1, no more than 10 percent; and for U.S. No. 2, no more than 20 percent of leaves may fail to meet the above requirements. For bunched spinach, there are two grades, U.S. No. 1 and U.S. No. 2, which both require similar varietal characteristics, and to be fresh, fairly clean, well-trimmed, and free from decay. For U.S. No 1, the bunch must be free from damage caused by coarse stalks, seed stems, buds, discoloration, wilting, insects, foreign material, as well as damage from mechanical or other means; for U.S. No. 2, the bunch must be free from serious damage from the above noted items.

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Generally speaking, the percentage of defects shown on a timely government inspection certificate should not exceed the percentage of allowable defects, provided: (1) transportation conditions were normal; (2) the USDA or CFIA inspection was timely; and (3) the entire lot was inspected. There are no good arrival guidelines for this commodity specific to Canada; U.S. guidelines apply to shipments unless otherwise agreed by contract. References: DRC, PACA, USDA.

Spinach Retail Pricing: Conventional & Organic