Leaf vegetable
Leaf vegetables, also called leafy greens, vegetable greens, or simply greens, are plant leaves eaten as a vegetable. Those eaten raw in a salad can be called salad greens, whereas leaf vegetables eaten cooked can be called pot herbs.
Nearly 1,000 species of plants with edible leaves are known. Leaf vegetables most often come from short-lived herbaceous plants, such as lettuce and spinach, but also come from some woody plants. The leaves of many fodder crops are also edible by humans, but usually only as famine or processed food.
Leaf vegetables contain many typical plant nutrients, but being photosynthetic tissues, their vitamin K levels are particularly notable. Accordingly, users of vitamin K antagonist medications like warfarin must limit their consumption of leaf vegetables.
Overview
Leaf vegetables are plant leaves eaten as a vegetable, sometimes accompanied by their petioles and shoots, if tender. Leaf vegetables eaten raw in a salad can be called salad greens, whereas leaf vegetables eaten cooked can be called pot herbs.Nearly 1,000 species of plants with edible leaves are known. Leaf vegetables most often come from short-lived herbaceous plants, such as lettuce and spinach, but also come from some woody plants.
The leaves of many fodder crops are also edible by humans, but usually only as famine food. Examples include alfalfa, clover, and most grasses, including wheat and barley. Food processing, such as drying and grinding into powder or pulping and pressing for juice, may involve these crop leaves in a diet.
List of leaf vegetables
- Agastache foeniculum — anise hyssop
- Allium fistulosum — Welsh onion
- Alternanthera sissoo — sissoo spinach
- Basella alba — Malabar spinach
- Beta vulgaris — beets, including beet greens, Swiss chard
- Brassica oleracea — wild cabbage, including cabbage, gai lan, Jersey cabbage, kale, red cabbage, savoy cabbage, collard greens, mustard greens, kohlrabi and more
- Brassica rapa — field mustard, including napa cabbage, bok choy, bomdong, choy sum, komatsuna, rapini, tatsoi, radish greens, and more
- Campanula versicolor — various-colored bellflower
- Chenopodium quinoa — quinoa
- Cichorium endivia — endive, including escarole
- Cichorium intybus — chicory
- Claytonia perfoliata — palsingat
- Cnidoscolus aconitifolius — chaya
- Daucus carota subsp. sativus — carrot
- Eruca sativa — arugula or rocket
- Foeniculum vulgare — fennel
- Gynura bicolor — edible gynura
- Gynura procumbens — longevity spinach
- Hemerocallis fulva — orange day-lily
- Lepidium meyenii — maca
- Lactuca sativa — lettuce, including celtuce, iceberg lettuce, red leaf lettuce, romaine lettuce
- Nasturtium officinale — watercress
- Malva moschata — musk mallow
- Moringa oleifera — moringa
- Perilla frutescens — shisho perilla
- Rumex acetosa — garden sorrel
- Sassafras albidum — sassafras
- Sauropus androgynus — katuk
- Spinacia oleracea — spinach
- Solanum aethiopicum — nakati
- Trigonella foenum-graecum — fenugreek
- Tropaeolum majus — garden nasturtium
- Viola odorata — sweet violet
Postharvest diseases
Common bacterial pathogens include: Xanthomonas campestris pv. vitians, Pseudomonas viridiflava, P. cichorii, P. marginalis, P. marginalis, P. viridiflava, P. syringae pv. aptata, X. campestris pv. campestris, X. campestris pv. raphani, P. syringae pv. maculicola, P. syringae pv. alisalensis, Pectobacterium spp. including P. carotovorum subsp. odoriferum and P. aroidearum, and Dickeya spp.
Common fungal pathogens include: Alternaria brassicicola, A. alternata, A. arborescens, A. tenuissima, A. japonica, Colletotrichum higginsianum, Colletotrichum dematium f. spinaciae, Microdochium panattonianum, Stemphylium botryosum, Cladosporium variabile, Cercospora beticola, C. lactucae-sativae, C. brassicicola, C. acetosella, Botrytis cinerea, Golovinomyces cichoracearum, Podosphaera fusca, Erysiphe cruciferarum, E. polygoni, E. heraclei, Sclerotinia sclerotiorum, and S. minor.
Common oomycete pathogens include: Albugo occidentalis, A. ipomoeae-aquaticae, A. candida, Hyaloperonospora parasitica, Bremia lactucae, Peronospora effusa, and Peronospora farinosa f.sp. betae.
Fungicides such as prochloraz can be used to manage some of these.
Nutrition
Spinach, as an example of a leaf vegetable, is low in calories and fat per calorie, and high in dietary fiber, vitamin C, pro-vitamin A carotenoids, folate, manganese and vitamin K.The vitamin K content of leaf vegetables is particularly high since these are photosynthetic tissues, and phylloquinone is involved in photosynthesis. Accordingly, users of vitamin K antagonist medications, such as warfarin, must take special care to limit the consumption of leaf vegetables.
Preparation
If leaves are cooked for food, they may be referred to in the United States as boiled greens. Leaf vegetables may be stir-fried, stewed, steamed, or consumed raw. Leaf vegetables stewed with pork is a traditional dish in soul food and Southern U.S. cuisine. They are also commonly eaten in South Asian dishes such as saag. Leafy greens can be used to wrap other ingredients into an edible package like a tortilla. Many green leafy vegetables, such as lettuce or spinach, can also be eaten raw, for example, in sandwiches or salads. A green smoothie enables large quantities of raw leafy greens to be consumed by blending the leaves with fruit and water.Africa
In certain countries of Africa, various species of nutritious amaranth are widely eaten boiled.Celosia argentea var. argentea or "Lagos spinach" is one of the main boiled greens in West African cuisine.
Greece
In Greek cuisine, khorta are a typical side dish, eaten hot or cold and usually seasoned with olive oil and lemon.At least 80 different kinds of greens are used, depending on the area and season, including black mustard, dandelion, wild sorrel, chicory, fennel, chard, kale, mallow, black nightshade, lamb's quarters, wild leeks, hoary mustard, charlock, smooth sow thistle and even the fresh leaves of the caper plant.
Italy
Preboggion, a mixture of different wild boiled leaf vegetables, is used in Ligurian cuisine to stuff ravioli and pansoti. One of the main ingredients of preboggion are borage leaves. Preboggion is also sometimes added to minestrone soup and frittata.Poland
is a soup that features beet stems and leaves as one of its main ingredients. The word "botwinka" is the diminutive form of "botwina" which refers to leafy vegetables like chard and beet leaves.United States
In the cuisine of the Southern U.S. and traditional African-American cuisine, turnip, collard, kale, garden cress, dandelion, mustard, and pokeweed greens are commonly cooked and often served with pieces of ham or bacon. The boiling water, called potlikker, is used as broth. Water in which pokeweed has been prepared contains toxins that have been removed by boiling and should be discarded.Sauteed escarole is a primary ingredient in the Italian-American dish Utica greens.