Dm / F# dim / F#
Spinach, Is one of the most nutritious, Vegetables, It's really good for us. Given our health variables, Would you fetch, Some more spinach? 2,000 years ago, Iranians knew how to grow, And, did you know, It went on to become, The Arabs "Prince Of Vegetables"? It makes me strong and able, So, how come, We don't fetch, Some more spinach? It's stuffed with beta-carotene, And, given a chance, On second glance, It just might, Give cancer, A Popeye fight, Do you know what I mean? It can help prevent, An ulcer, And, is essential, For keeping red blood cells, Well. Why do I need to appreciate, Folate? Well, If I ate, Enough folate, I might go another day, Without my hair turning gray, Developing an anemia, Stunted growth or diarrhea, Er, a... I guess I should make vitamin B9, A better friend of mine, So, would you mind, If I fetch, Some more spinach I think I'll try, The same as Popeye, To be an advocate... Show how much I appreciate, Spinach, Yes, I'll try it for a switch.
NOTES
From The National Institute Of Health
Folic acid (folate)
Alternative names
Vitamin B9; Folate; Diet - folic acid; Pteroylglutamic acid
Definition
Folic acid is a water-soluble vitamin in the B-complex
group.
Function
Folic acid works along with vitamin B12 and vitamin C to
help the body digest and utilize proteins and to
synthesize new proteins when they are needed. It is
necessary for the production of red blood cells and for
the synthesis of DNA (which controls heredity and is
used to guide the cell in its daily activities).
Folic acid also helps with tissue growth and cell function. In addition, it helps to increase appetite when needed and stimulates the formation of digestive acids.
Synthetic folic acid supplements may be used in the treatment of disorders associated with folic acid deficiency and may also be part of the recommended treatment for certain menstrual problems and leg ulcers.
Food Sources
oBeans and legumes
oCitrus fruits and juices
oWheat bran and other whole grains
oDark green leafy vegetables
oPoultry, pork, shellfish
oLiver
Side Effects
Folic acid deficiency may cause poor growth, graying
hair, inflammation of the tongue (glossitis), mouth
ulcers, peptic ulcer, and diarrhea. It may also lead to
certain types of anemias. Toxicity from excessive folic
acid intake does not normally occur, as folic acid is
water soluble and regularly excreted by the body.
Recommendations
Recommended daily allowances (RDAs) are defined as the
levels of intake of essential nutrients that, on the
basis of scientific knowledge, the Food and Nutrition
Board judges to be adequate to meet the known nutrient
needs of practically all healthy persons.
The best way to get the daily requirement of essential vitamins is to eat a balanced diet that contains a variety of foods from the food guide pyramid.
Most people in the United States have an adequate dietary intake of folic acid because it is plentiful in the food supply.
However, pregnant women often require additional supplementation as prescribed by a health care provider. Adequate folic acid is important for pregnant women because it has been shown to prevent some kinds of birth defects, including neural tube defects such as spina bifida. Many foods are now fortified with folic acid to help prevent these kinds of birth defects.
Women in their childbearing years should make an effort to consume foods that are good sources of folic acid. Studies published by the Centers for Disease Control and Prevention (CDC) suggest that women who receive supplements of folic acid BEFORE CONCEPTION may reduce the risk for neural tube defects by 50%. Women who plan to become pregnant may want to discuss taking a multivitamin with their health care provider if they are not already doing so.
Specific recommendations for each vitamin depend on age, gender, and other factors (such as pregnancy). The U.S. Department of Agriculture offers a PDF file that lists these recommendations.
Update Date: 1/19/2003
From The University Of Georgia:
FAMILY CHARACTERISTICS
Many plants are harvested for the use of their leaves. Leafy
plants are referred to as greens or potherbs and include spinach,
kale, collards, and mustard. Swiss hard (Beta vulgaris L. subsp.
cicla) and beets (Beta vulgaris L. subsp. vulgaris) are in the same
family and the leafy foliage of these plants are consumed in the
same way as members of thespinach family. Other common plants
in the spinach family are the sugar beet, lambs quarter,
and glasswort. The plants in this family are
dicotyledons. There are about 102 genera and 1,400
species in the world. The plants are similar in
characteristics, usually having alternate and simple
leaves. The inflorescence is cymose, often bracteate,
and flowers are small and inconspicuous. Many of the
plants in this family are thought to have originated in
southwestern Asia and were introduced into Europe in the
Middle ages.
European settlers brought members of this family to N. American as they settled in the New World.
Family members include:
Atriplex hortensis L., Orache
Beta vulgaris L., Beet
Beta vulgaris L. (Cicla group), Chard
Chenopodium bonus-henricus L., Good King Henry,
Mercury
Spinacia oleracea L., Spinach
CROP HISTORY AND DEVELOPMENT
Spinach was cultivated over 2,000 years ago in Iran.
Cultivation of spinach began during the Greek and Roman
civilizations. Our name for spinach is derived from
the Persian ward "ispanai" which mean "green hand" which
later became "spanachia"(Late Latin), to spinach and
spinach and spinage (English). The Arabs named it 'the
prince of vegetables'. In 647 A.D. spinach was
introduced into China and was then transported to Spain
in 1100. The prickly seeded form was known in Germany
in the 13th century and the smooth seeded form was not
described until 1552. It is the smooth seeded form that
is used today in commercial production. By 1806,
spinach had become a popular vegetable and was listed in
American seed catalogs. In the 1920's the U.S.
pushed spinach commercially, with Popeye the Sailorman
cartoon being a great advocate in spinach consumption.
Spinach is used as a leafy green and eaten raw in salads. It is also used as a cooked green (potherb) much like turnip greens or collard greens.
Nutritional Constituents
Spinach contains large amounts of minerals and vitamins,
especially vitamin A, calcium, phosphorus, iron and
potassium. Spinach also has high levels of protein.
Ninety-one percent of spinach weight is water. A serving of spinach contains 3.2 grams of protein, 4.3 grams of carbohydrates, and 0.3 grams of fat. It also contains Vitamin A, and C, thiamin, riboflavin, and niacin. Calcium, phosphorus, iron, sodium, and potassium are also found in spinach greens.
Production
Spinach is grown across the US from California to
Florida. California is responsible for over one half of
the production in the US. Texas is also a large producer
of spinach, about one third of the total crop in the US.
Colorado, Florida and New Jersey also have significant
acreage.
California is a leader in the processing industry, producing over one third of the total US production. Arkansas and Oklahoma produce the remaining of the processed spinach.
Cultivars and Varieties
It is important to choose the proper variety for disease
and insect resistance. It is also important to choose a
variety that will be adequate for the season in which it
will be grown. If growing in the late spring or summer,
slow growing and slow bolting varieties are preferred.
If growing in the fall, winter, or early spring, fast
growing varieties should be used. There are three types
of spinach: the smooth leaf, the savoyed leaf, which is the
traditional Eastern style with a textured
appearance, and the semi-savoyed, used for fresh market
or processing. The smooth leaf and semi-savoy are used
mainly for processing, while the savoy is used for fresh
market. The savoy types are better for shipping because
they are less likely to wilt or turn yellow before
reaching the market. The smooth leaf are easier to
clean and remove soil from leaves before canning or
freezing for processing.
Smooth Leaf Types-
'Denali' (F1)- 36 days, white rust and mildew tolerant, moderately
slow bolting.
'Hector' (F1)- 37 days, downy mildew resistant. Ideal for salad.
'Space' (F1)- 39 days, high yielding, downy mildew resistant. Good
greenhouse performer.
Semi-savoyed Leaf Types-
'Melody' (F1)- good for spring and fall crops, downy mildew and
cucumber mosaic virus resistant
'Coho' (F1)- 37 days, white rust tolerant, moderate bolt tolerance
'Indian Summer' (F1)- good greenhouse performer, cucumber mosaic
virus and downy mildew resistance.
Savoy Leaf Types-(textured appearance)
'Tyee' (F1)- 42 days, the most bolt resistant savoy type.
'Vienna' (F1)- upright, good for spring and fall plantings.
Some downy mildew resistance.
'Savoy Hybrid'- good fall crop for shipping and freezing.
Resistant to downy mildew and cucumber mosaic virus.
Specialty Type- 'Tetragonia' (Tetragonia etragonioides) (New Zealand Spinach) 50 days. Spinach like plant that tolerates hot weather better than spinach. It is actually a warm season crop and must be planted after the danger of frost is over. 'Tetragonia' is native to New Zealand, Japan, and Australia. It was introduced into England in the 1700's. The seeds are very slow to germinate so they should be soaked before planting. It will grow 2 or more feet with a spreading, branching habit of 4-6 feet. The New Zealand spinach does not have any disease or insect problems of consequence.
Processing Spinach- 'Seven R' - semi-savoy type. Plants are large and grow quickly. It is good for mechanical harvesting and processing. It has resistance to downy mildew.
Greenhouse Spinach- Spinach can be grown hydroponically in the greenhouse. The cultivars 'Indian Summer' and 'Space' are two good types that do well in the greenhouse.
PLANT CHARACTERISTICS
Overview. The spinach used for fresh market, processing
and greenhouse, are all of the same species, therefore
have the same plant characteristics. Spinach is a cool
season annual herb. It can survive severe frosts in the
winter.
Root System. Spinach has a taproot that is deep and has branching roots in the top 6-10 inches of soil. These roots can extend to several feet, but the feeder roots remain in the top 2-4 inches of the soil. The system is generally thick and shallow.
Stem and Leaves. Spinach is a fleshy leaf annual that grows in a rosette. The leaves are glabrous non-hairy), broad and tender. The leaves may be savoy (puckered or crinkled), semi-savoy, or smooth. The leaves are lobed at the base and sometimes lobed on the sides. The stem is edible as well, but tougher than the leaves. The stem is the development of the reproductive stage. The branching seed stalk and pointed leaves develop on the central stem.
Flowers and Fruit. The plant can bear either male or female flowers on the same plant. Sex expression varies, the plants are primarily dioecious. The flowers are inconspicuous, greenish-white, and are borne in clusters on a spike. The female flowers develop into seed like fruit. Male plants usually bolt faster than female. The flowers are wind pollinated. Spinach becomes reproductive in response to the day length and temperature conditions. As day length reaches 15 hours, the development of the seed stalk takes place and is accelerated in 40-50°F temperatures. The seed stalk is hollow and can reach 4-5 feet high.
Seed. There are about 90 seeds per gram, 2,500 seeds per ounce, and about 40,000 seeds per pound. It takes about 8 days for seed to germinate. Seeds should be planted between ½ to 1 inch deep. One acre requires between 10-15 pounds of seed for direct seeding. The plant turns yellow as the seeds are reaching maturity. The seed are round or prickly depending on the cultivar selected.
PROPAGATION METHODS
Temperatures. Spinach is classified as a hardy cool
season crop. It can be grown most anywhere in the US,
but does best in 50-60°F temperatures. It will not
germinate well in hot weather; if soil temperatures
exceed 85°F the seeds may become dormant.
Direct seeding. Transplants are not used commercially, but are good for home gardens. All commercial production is direct seeded with little or no thinning.
The seed is either broadcast or sown in rows on wide beds. There should be 2-6 inches in between plants in the row. The distance between rows should be 12 to 36 inches. Spinach seeds need consistent soil moisture for proper germination. Being a cool season crop, the seed should be sowed when the ground is cool in early spring. For a fall crop, the seed can be sown from July to September. Seeding time for the coastal plain is February to March, and mid-August to late October, in the Piedmont, from late February to early April and from August to mid-October, and in the mountains, from March to April and mid-July to mid-September.
CULTURAL PRACTICES
Overview. Spinach has two stages in its life cycle;
the vegetative, rosette stage and the bolting, seed
stalk stage. It is important that the plants be
maintained to avoid bolting. Once the plant bolts it is
no longer marketable. The first stage is relatively short
(about 35-40 days) and must be watched very closely to
maintain good quality.
Soils. Spinach can grow in a range of soils as long as they are moist and fertile. Fertile, sandy loams, high in organic matter is recommended. The plants are sensitive to acidity and the soil should be at least a pH of 6.0, with an optimum pH of 6.2-6.9. The symptoms of low pH are low germination, yellowing and browning of the margins and tips of seedling leaves, browning of roots, general slow growth, and even the death of the plant.
Fertility. Spinach from the field should be tested for nutrient levels by collecting about 15 of the most recently fully developed leaves. When the plant is 30-50 days old, the nitrogen levels should be around 4.0-6.0%, phosphorus 0.3-0.6%, potassium 5.0-8.0%, and calcium 0.7-1.2%.
Before planting in early spring, 85-125 lbs N, 75-85 lbs P205, and 85-125 lbs K20 should be added to the soil, depending on soil test results. If the fertilizer is added during seeding it should be banded 2-3 inches below the seed and 6 inches to the side. The fertilizer should not come in contact with the seed.
Weed Control. Cultivation is done in spinach fields, but it should be shallow as to not harm any of the roots. Spinach does not compete well with weeds. Usually 2-4 cultivations are sufficient during the growing season.
Irrigation. With the root system being mostly shallow, spinach does best in uniformly moist conditions. Fields are irrigated by either flooding, furrow, or overhead sprinklers. An application every 7-10 days of 1 inch of water is recommended during dry periods without rainfall. Overhead irrigation can reduce yields by increasing the risk and levels of disease because many diseases thrive in moist, humid conditions. Therefore it is recommended to use furrow or flooding irrigation. It is important to keep soil moist when seeds are germinating.
INSECTS
All crops produced are susceptible to insect damage.
Pest management must be carefully controlled in leafy
greens. Any defects in the leafy green causes the
quality to decline. Consumers do not want spinach with
insect damage that are portrayed as holes in the leaf.
Unfortunately, for this reason, pesticides are highly
used on spinach. It is important to use pesticides
safely, to read the label and wear protective gear.
Insecticides are constantly changing labels, laws, and
regulations.
It would be beneficial to check with the extension service to find out which insecticides do best in certain areas.
Green Peach Aphid- (Myzus persicae) is a very detrimental insect to spinach. It is so dangerous because it can transmit diseases that can wipe out large portions of the crop. The aphid is pale yellowish in color and is small. It lives mainly on the underside of leaves and therefore is hard to control by spraying.
Spinach Leafminer- (Pegomyia hyoscyami) this is a serious insect that causes much damage in spinach in many areas across the United States.
Budworm injury- (Hylemya cilicrura) This is the seed corn maggot. The larvae feed on young leaves. The cucumber beetle feeds on older leaf spinach. The damage found on spinach by both of these insects can usually be found on fresh market spinach.
Other Insect Pests. Cabbage looper, cucumber beetle, flea beetles, root maggots and cutworms. The aphid and the leaf minor are cause the most serious damage.
DISEASES
The quality and marketability of spinach is reduced with
even the slightest amount of defects.
Downy Mildew- (Peronospora spinaciae) This is a fungus that is distributed worldwide and is particularly bad in the southern US and coastal regions. It causes leaf spotting that detracts from the quality and appearance. The fungus increases profusely in high humidity. The spores can over winter in mild climates, but usually blow in from conidia. The best control measure is the use of resistant varieties.
Bacterial Soft rot (Erwinia carotovora) is one of the most important diseases. Its symptoms include water soaked tissue and muddy-green or greasy appearance of leaves. Rapid decay occurs and the tissue becomes wet and mushy. This bacteria is found in the soil and in plant debris. It can enter into the plant through mechanical injury, insect injury, disease lesions and other skin punctures.
Fusarium Wilt- (Fusarium oxysporum f. sp. spinaciae) is a wilt that is caused by a fungus. The plants become pale green, the leaf margins roll inward and the plant begins to die. The fungus is transferred through contaminated seed and soil.
White Rust (Albugo occidentalis)- Is a fungus that cause white blister-like pustules on the underside of leaves. They are filled with white spores and the surrounding tissue turns brown and dies. It occurs most frequently in Texas and the southwestern states. The fungus favors clear, warm, and dry days with cool nights.
Other Important Diseases- Curly top virus- vein clearing on young leaves. The leafhopper is a vector. Mosaic, caused by the cucumber mosaic virus, transmitted by the green peach aphid.
Young leaves begin to mottle, become yellow and die. Intensity of the virus increases under long days and intense light. There are some varieties resistant to these viruses.
Spinach Blight, Yellows- Are spread mechanically and by the green peach aphid. The plants show a light yellowing and malformation of young leaves.
HARVESTING
Spinach usually matures in 37-70 days, most are within
40-50 days. Spinach should be harvested before bolting
to reduce yellowing, breakage and other leaf
deterioration, and to avoid development of the seed
stalk.
Fresh Market- An acre of fresh spinach will yield 4 to 8 tons/acre, on average 6,000 pounds per acre. The plant may be harvested from the time there are 5-6 leaves on the plant until right before the seed stalk develops. After the seed stalk has developed the plant is no longer marketable.
For fresh Market the entire rosette is cut mechanically at the soil surface. The plant is then put into bulk trucks or trailers.
Processing- The spinach is cut about an inch above the soil surface, allowing regrowth. Many times, two harvests are possible before the plant develops a seed stalk. Spinach meant for processing has a higher yield per acre because of the dense planting, an average 13,200 pounds per acre could be expected. Yields vary widely due to seasonal and environmental conditions.
POST HARVEST
Spinach should be held at 32°F and 95 to 100% relative
humidity. Spinach will perish very quickly, and can
only be stored from 10-14 days. When taken from the
field, rapid cooling is essential, usually done by a
vacuum system, or hydrocooling.
Excess water is removed and then the product is shipped with ice to preserve the freshness. Much of the spinach for fresh market is put into plastic bags to reduce physical injury and moisture loss. It is usually packed in 20 lb cartons with 2 dozen bunches. Spinach can also be sold loose, in bunches or in polyethylene bags.