Modern cabbages in the genus Brassica are descended from leafy wild mustard plants native to the Mediterranean seacoast.
Used for both eating and edible ornamental landscaping, cabbages are usually classified as either regular head cabbage (B. oleracea var capitate) or Chinese, sometimes called Napa cabbage (B. campestris var. pekinensis).
Both types consist of leaves layered one upon another to form a ball. While head cabbages are usually compact and round, Napa cabbages are typically looser and may be either cylindrical or round, resembling a tighter head of romaine lettuce.
Cultivated for centuries in China, the plant’s popularity across Europe may be attributable to the Celts, who brought the plant back from invasions into Asia Minor, eventually passing it on to the conquering Romans.
The Romans spread cabbage farther although it wasn’t introduced to America until much later when Europeans and colonists brought it to the New World.
Napa cabbage has a milder taste than regular green head cabbage and is often used for soups, pickling, stir fry, or egg rolls. Head cabbage is used in a variety of dishes like coleslaw and sauerkraut and has become one of the world’s most popular vegetables particularly in Russia, Poland, and Germany.
Types & Varieties
About 45% of cabbage is used in processing to make coleslaw. Fresh cabbage sold by the head makes up more than a third of the market, followed by sauerkraut and other uses. While there are hundreds of cabbage varieties, the four primary types are green, red, Savoy, and Tuscan.
Green cabbage includes both regular head cabbage and Chinese or Napa types, including a variety of Asian cabbages. With smooth, dark to pale green outer leaves, the inner leaves of green cabbage tend to be white.
Green head cabbage can be classified as Danish, domestic, or pointed. Danish heads are round, solid, and compact. Domestic are also round, but the leaves are less compact and will grow a looser head. Pointed are smaller and more conical in both leaves and the overall head.
Asian green cabbage types are harder to pin down as various regions and markets name them differently. Most types include the word “choy,” which is a generic word for vegetable. These Chinese cabbages include bok choy, choy sum, gai choy, and Napa cabbage.
Red cabbage differs from green mostly in its red to purple outer leaves that are streaked with white on the inside. It has a flavor similar to that of green cabbage, but leaves may have a tougher texture.
Savoy cabbage is distinguished by its attractive crinkled leaves and mild flavor. Savoy is commonly used for coleslaw and salads. Leaves are yellow-green and the head is not as compact as other cabbage types.
Tuscan cabbage is somewhat new to the United States and may be harder to find. Its dark green, white-ribbed leaves have a mild flavor and heads tend to be longer and narrower than other cabbage types.
Cabbage is a cool-weather crop requiring consistently moist, well-drained soil with a pH from 6 to 7.5, high in organic matter. Cabbage plants can germinate in soil as cool as 40°F. Crops grow best in full sun, but may need moderate shade in hotter temperatures, although shade will slow plant maturity.
Crops can be direct-seeded or transplanted. In general, early season varieties produce 1- to 3-pound cabbages and late varieties produce 4- to 8-pound cabbages.
Heavy freezes can damage inner leaves even when outer leaves show no sign of damage, while sudden soaking rains can cause heads to split.
Harvest can occur anytime after heads are both solid and compact, only slightly yielding when squeezed. Cabbage is usually harvested by hand in the field. It is packed unwashed into either bags destined for pallets and shipping or into cartons or crates for storage and delivery.
Heads are easily bruised and must be handled carefully and not over-trimmed, which will result in wilted inner leaves and bruising or cuts. Picking during the coolest part of the day is ideal to minimize damage.
Pests & Diseases
Pests of concern include mites, diamondback moths, loopers, aphids, root maggots, beet armyworms, webworms, cutworms, mole crickets, silverleaf whiteflies, flea beetles, slugs, and nematodes.
Diseases common to cabbage are black rot, downy mildew, alternaria leaf spot, damping-off, turnip mosaic, wirestem, cabbage yellows, clubroot, purple blotch, yellow or fusarium wilt, watery soft rot, and grey mold.
Storage & Packaging
Cabbage is usually room cooled and stored at 32°F from 3 weeks to 6 months, depending on cultivar. Chinese cabbage is slightly hardier, generally lasting from 2 to 6 months.
To prevent freezing injury, round cabbage should be kept no cooler than 30.4°F and Chinese cabbage no cooler than 31°F with 90 to 95% relative humidity. Cabbage is sensitive to ethylene and should be stored in a well-ventilated area.
References: Texas A&M Agrilife Extension, UC Davis Postharvest Technology Center, University of Florida/IFAS Extension, University of Illinois Extension, Western Growers Association.
GRADES & GOOD ARRIVAL
Cabbage is graded as U.S. No. 1 and U.S. Commercial: U.S. No. 1 consists of heads of one variety with reasonable solidity, no withering or puffiness, and free from soft rot, seed stems, discoloration, and damage from disease, insects, and freezing or mechanical injury. Stems should not extend more than half an inch beyond outermost leaves. Heads should be well trimmed unless U.S. No. 1 Green or New Red, which are to be fairly well trimmed.
For U.S. Commercial cabbage, heads be reasonably firm and well-trimmed unless classified as U.S. Commercial Green or New Red, which requires fairly good coloring and trimming.
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.
|U.S. Grade Standards||Days Since Shipment||% of Defects Allowed||Optimum Transit Temp. (F)|
Canadian good arrival guidelines (unless otherwise noted) are broken down into five parts as follows: maximum percentage of defects, maximum percentage of permanent defects, maximum percentage for any single permanent defect, maximum percentage for any single condition defect, and maximum for decay. Canadian destination guidelines are 15-10-5-10-4.
References: DRC, PACA, USDA.
• Aphids, live or dead, are scored as a defect when more than 10 are found on the compact portion of the head
• Worm holes penetrating 3 or more head leaves shall be considered a defect
• Tipburn starts as small spots or narrow lesions along the edge of a leaf that are bleached light yellow to off-white; later, the affected areas usually enlarge and turn yellowish-brown to brown—score as damage when present on more than 3 head leaves or when the aggregate area exceeds a 1×2 inch rectangle
• As sunscald progresses, the affected area begins to dry out and results in a bleached, papery, or parchment-like area surrounded by healthy tissue—score as damage when the affected area exceeds more than 25% of the crown area or penetrates more than 2 head leaves.
Source: Tom Yawman, International Produce Training, www.ipt.us.com.