Brassica oleracea (Capitata Group)
Last revised January,14 2010
Photo credit: Alex Stone, Oregon State University
VARIETIES (approximately 75 days for early varieties, 90 days for mid-season, to over 120 days for late large-headed varieties).
Excellent cabbage varieties are available that are resistant to heat, cold, and a number of important diseases and physiological disorders. See the Vegetable Variety Selection Resources page to find varieties that have been shown to perform well in the Pacific NW.
Important Considerations for Field Selection
Before planting this Crucifer crop, consider the following important factors which affect a number of diseases such as club root and Sclerotinia:
1. No crucifer crop, or related weed has been present in the field for at least 2 years, 4 years preferable. Crucifer crops include cabbage, cauliflower, broccoli, kale, kohlrabi, Brussels sprouts, Chinese cabbage, all mustards, turnips, rutabagas, radishes etc. Cruciferous weeds include wild radish, shepherdspurse, wild mustards etc. Also, crucifer plant waste should not have been dumped on these fields.
2. On soils with history of club root, soil pH over 6.8 is necessary to manage club root. The application of 1500 lb/acre of hydrated lime, 6 weeks prior to planting is recommended for soils with pH less than 7.5 for club root control (see Disease Control section for more details). Otherwise soil pH should be over 6.5.
3. Arrange to keep transplanted and direct-seeded fields separate to minimize spread of certain diseases that are more prevalent in transplanted fields.
SEED AND SEED-BED TREATMENTS
Cabbage seed numbers approximately 144,000 per pound. Pelletizing is not necessary but primed and coated seed is becoming more common. Consult your seed dealer about the availability of primed seed. Cabbage is both direct seeded and transplanted.
Use treated seed to protect against several serious seed-borne diseases. Hot water seed treatment is used under certain conditions (especially for transplant production). This treatment is very specific (122 F exactly, for 25 to 30 minutes; the wet seed must then be quickly cooled and dried). Hot water seed treatment is best done by the seed company, and can usually be provided upon request.
TRANSPLANT PRODUCTION
Seedbeds for Transplants:
When seedlings are to be grown in a seed-bed for production of transplants, choose a site where cole crops have not been grown before, or fumigate before seeding with an approved fumigant following label and manufacturer's recommendations.
Always use certified or hot water treated seed for transplant production. Seed in a greenhouse for an early crop, in a cold frame for a less early crop, and in outdoor seedbeds when the weather is warm enough for germination and growth (above 50 F). In each case seed 5-6 weeks ahead of when the plants are wanted for transplanting.
Four to 6 ounces of high quality, sized and density graded seed will provide enough transplants to plant 1 acre. In the seedbed use a drill with a scatter shoe to drop 15 to 20 seeds per foot in rows 10 inches apart.
Greenhouse Transplant Production
Precision seed into modular flats, styrofoam trays or blocks of a peat-lite (peat vermiculite) mix or other suitable growing medium. Crowding should be avoided. Provide 1.5-2.5 square inches per plant in modular trays.
Temperatures should be maintained above 45 F at night and below 85 F during the day. About 4-5 weeks are needed. Seven days before transplanting start the hardening off process.
Follow the same process in a cold frame, or seed directly into the covered soil after it has been limed, fertilized and fumigated as for outdoor seedbeds.
FIELD SEEDING
In western Oregon fresh market cabbage may be field seeded or transplanted from mid March to August 10. Cabbage for processing is generally seeded from mid April to the end of July.
Preparation for direct seeding needs the same attention a seed bed area would be given. A fine textured soil, free of rocks, clods and trash, firm and very level, is required for precision seeding. Approximately 0.5 to 1.5 lb of seed are needed per acre depending on whether a precision or non-precision planter is used.
Use a precision seeder such as a Stanhay, or Gaspardo vacuum planter, to drop 2 seeds 2 inches apart every 15 inches. After the first true leaves have formed, thin to one plant per location. In continuous seeding, thin the plants so as to leave 15 to 18 inches between them. Spacing between rows should also be 15 to 18 inches. Growers usually plant 4 rows per set or bed, leaving the necessary distance between sets to accommodate tractor tire width as shown schematically:
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SOIL
Cabbage may be grown on a variety of soils but it does best on a well- drained, loam soil well supplied with organic matter. Sandy loams are preferred for early crops. Adjust soil pH to 6.5 - 7.0 for maximum yields.
FERTILIZER
For the most current advice, see Nutrient Management for Sustainable Vegetable Cropping Systems in Western Oregon, available as a free download from the OSU Extension Catalog
A soil test is the most accurate guide to fertilizer requirements. The following recommendations are general guidelines for western Oregon:
Good management practices are essential if optimum fertilizer responses are to be realized in the production of cabbage. These practices include use of recommended varieties, selection of adapted soils, weed control, disease and insect control, good seedbed preparation, proper seeding methods, and timely harvest.
Because of the influence of soil type, climatic conditions, and other cultural practices, crop responses from fertilizer may not always be accurately predicted. Soil test results, field experience, and knowledge of specific crop requirements help determine the nutrients needed and the rate of application.
The fertilizer application for cabbage should insure adequate levels of all nutrients. Optimum fertilization is intended to produce top quality and yields in keeping with maximum returns.
Recommended soil sampling procedures should be followed in order to estimate fertilizer needs. The Oregon State University Extension Service agent in your county can provide you with soil sampling instructions, soil sample bags, and information sheets.
Where cabbage is direct-seeded, see "field fertilization" section below. If transplants are to be used, and if transplants are to be field grown, fertilize transplant productions beds as follows:
TRANSPLANT BED FERTILIZATION
Broadcast and work into the transplant bed:
1. 40 to 70 lb N/Acre.
2. Apply phosphorus, potassium, sulfur, magnesium, boron, molybdenum, and lime up to the maximum rates suggested below for field applications.
TRANSPLANTING SOLUTIONS
Dilute solutions of complete fertilizers high in phosphorus promote quick recovery and early growth of transplants. One-half pint of transplanting solution should be injected into the furrow at the roots of each plant at time of transplanting. A transplanting solution may be prepared by dissolving 3 lb of 11-48-0 or similar monoammonium phosphate fertilizer in a 55-gallon drum of water. Diammonium forms may cause foliar burn on seedlings.
FIELD FERTILIZATION
NITROGEN (N):
A total application of 80-100 lb N/A is suggested.
Broadcast about half of the N just before direct seeding or transplanting or band 60-90 lb N/A with the phosphorus. Broadcast the remaining nitrogen just before the last cultivation, or 1 to 2 weeks before the first cutting. At the higher rates, two applications should be made 2 to 3 weeks apart.
For Nitrogen liquid formulations for weed control in cabbage, see the file N Fertilizer Solutions Providing Ancillary Weed Control in Cole Crops.
PHOSPHORUS (P):
Phosphorus fertilizer should be banded at the time of seeding or transplanting. Bands should be located 2-3 inches to the side of the seeds or plants and 3-4 inches deep.
| If the soil test* for P reads (ppm): | Apply this amount of phosphate (P2O5,lb/A): |
|---|---|
| 0 - 30 | 150 - 200 |
| 30 - 50 | 100 - 150 |
| Over 25 | 80 - 100 |
*Assumes extraction procedures similar to those used by the OSU Central Analytical Laboratory. Specific information on soil test procedures is available from the Dept. of Crop and Soil Science.
POTASSIUM (K):
Limit band applications of K to 90 lb K2O/A. Broadcast remainder of K and work into seedbed prior to planting. The total of N plus K2O in the band should not exceed 90 lb/A. Apply K as follows:
|
If the soil test* for K reads (ppm): |
Apply this amount of potash (K2O, lb/A): |
|---|---|
| 0 - 150 | 150 - 200 |
| 150 - 200 | 90 - 150 |
| 200 - 250 | 60 - 90 |
| Over 250 | None |
*Assumes extraction procedures similar to those used by the OSU Central Analytical Laboratory. Specific information on soil test procedures is available from the Dept. of Crop and Soil Science.
SULFUR (S):
Include 25-40 lb/A of S in the fertilizer program. S is sometimes contained in fertilizers used to supply other nutrients such as N, P, and K, but may not be present in sufficient quantity.
Plants absorb S in the form of sulfate. Fertilizer materials supply S in the form of sulfate and elemental S. Elemental S must convert to sulfate in the soil before the S becomes avail able to plants. The conversion of elemental S to sulfate is usually rapid for fine ground (less than 40 mesh) material in warm moist soil). Sulfur in the sulfate form can be applied at planting time. Some S fertilizer materials such as elemental S and ammonium sulfate have an acidifying effect on soil.
The S requirements of crucifers can be provided by:
Applying 25-40 lb S/A in the form of sulfate at or before seeding or planting.
Applying 40-50 lb S/A as fine ground (finer than 40 mesh) elemental S the preceding year.
Applying coarser ground elemental S at higher rates and less frequently.
MAGNESIUM (Mg):
When the soil test value for Mg is below 2 meq/100g soil, band 15- 20 lb Mg/A at transplanting or seeding time. If Mg deficiency symptoms develop, spray with 10 lb Epsom salts in 100 gal water/A.
Magnesium can also be supplied in dolomite, which is a liming material and reduces soil acidity to about the same degree as ground limestone. Dolomite should be mixed into the seedbed at least several weeks in advance of seeding and preferably the preceding year. It can also be supplied by the application of Epsom salts or Sul-Po-Mag fertilizer prior to seeding or transplanting as follows:
* Sul-Po-Mag at 150 to 200 lb/acre.
* OR Epsom salts at 150 to 200 lb/acre.
* OR Dolomitic Limestone at 225 to 275 lb/acre.
BORON (B):
Cabbage is sensitive to boron deficiency. Apply boron as follows:
|
If the soil test* for B reads (ppm): |
Apply this amount of B (lb/A): |
|---|---|
| 0 - 1 | 3 - 4 broadcast |
| 1 - 3 | 1 - 2 broadcast |
| Over 3 | 1/2 - 1 foliar spray |
*Assumes extraction procedures similar to those used by the OSU Central Analytical Laboratory. Specific information on soil test procedures is available from the Dept. of Crop and Soil Science.
A satisfactory foliar spray contains 1 lb B/100 gal water. Fertilizers containing B should not be banded.
Fields East of the Cascades or where winter rainfall is low, and to which the higher rates of boron has been applied should not normally be planted to beans or cucumbers the following year, as both these crops are extremely sensitive to boron.
LIME:
If a mineral soil is below pH 6.3 or an organic soil is below 5.5 and/or the calcium (Ca) level is below 8 meq/100g soil lime should be applied. Compared to other vegetables cabbage has a fairly high lime requirement.
The application of lime is suggested when the soil pH is below 6.3
| If the SMP Buffer* test for lime reads: | Apply this amount of lime (T/A): |
|---|---|
| Below 5.6 | 5 - 7 |
| 5.7 - 5.9 | 4 - 5 |
| 5.9 - 6.1 | 3 - 4 |
| 6.1 - 6.3 | 2 - 3 |
| 6.3 - 6.6 | 1 - 2 |
| Over 6.6 | None |
*Assumes extraction procedures similar to those used by the OSU Central Analytical Laboratory. Specific information on soil test procedures is available from the Dept. of Crop and Soil Science.
The liming rate is based on 100-score lime. Lime should be mixed into the seedbed at least several weeks before seeding and preferably the preceding year. A lime application is effective over several years.
Some soils may have a fairly high SMP buffer value (over 6.6) and a low pH (below 6.0). This condition can be caused by the application of acidifying fertilizer. In this case the low pH value is temporary and the pH of the soil will increase as the fertilizer completes its reaction with the soil. This temporary "active" acidity from fertilizer is encountered following recent applications of most nitrogen fertilizer materials. Acidifying fertilizers also have a long term acidifying effect on soil that is cumulative and leads to lower SMP buffer readings.
Sandy soils to which fertilizers have not been recently applied sometimes record low pH and high SMP buffer values. In such cases, a light application of lime (1 to 2 ton/A) should suffice to neutralize soil acidity.
For acid soils low in Mg (less than 0.5 meq Mg/100g soil) one T/A of dolomite lime can be used as a Mg source. Dolomite and ground limestone have about the same ability to neutralize soil acidity.
The P, K, Mg, B and lime recommendations are based on soil test values from the Soil Testing Laboratory, OSU, Corvallis, Oregon.
These recommendations are largely based on the results of experiments conducted by Oregon State University Agricultural Experiment Station Horticulture and Crop and Soil Science Department research faculty.
These recommendations are adapted from OSU Fertilizer Guide FG 27.
IRRIGATION
In soil suspected of having club root, care should be taken in not over-watering transplants after setting them out. A total of 10-14 inches of water may be needed for direct seeded fields and 10-12 inches for transplanted ones in western Oregon. Approximate summer irrigation needs for the Hermiston area have been found to be: 3.5 inches in May, 5.0 in June, 7.5 in July, and 7.0 in August.
Soil type does not affect the amount of total water needed, but does dictate frequency of water application. Lighter soils need more frequent water applications, but less water applied per application.
HARVESTING AND HANDLING
The University of California-Davis has a file on Minimal Processing of Fresh Vegetables that discusses film wrapping and other topics.
In western Oregon fresh market cabbage may be harvested from mid-July to the end of December. The main harvest period is between the first of August and mid November.
Cabbage for processing is generally harvested from about mid-July to mid November. Cabbage for processing should be delivered to the processor as soon after harvest as possible
Average yields of processed cabbage in the Pacific Northwest are approximately 30 tons/acre with good yields about 40 tons/acre. Average fresh market yield is reported at 235 cwt/acre with good yields about 300 cwt/acre.
Processed cabbage can be machine harvested, but is usually hand harvested in the Pacific Northwest. All fresh market cabbage is hand harvested. A company that advertises the "King Cole" Fresh Market Cabbage Harvesters and Systems is "MACH-WELD" Mfg. Co., Clyde, OH 43410.
Heads should be harvested when firm and before they split or burst. In harvesting for fresh market, leave 4-6 wrapper leaves attached to the head. The wrapper leaves are usually removed when harvesting for kraut.
STORAGE (Quoted or modified from USDA Ag. Handbook 66 and other sources)
Store cabbage at 32 F and a relative humidity of 98 to 100%. A large percentage of the late crop of cabbage is stored and sold during the winter and early spring, or until the new crop from the southern states appears on the market. If stored under proper conditions late cabbage should keep for 5 to 6 months. The longest keeping cultivars belong to the Danish class. Early-crop cabbage, especially southern grown, has a storage life of 3 to 6 weeks.
Cabbage is successfully held in common storage in the northern states, where a fairly uniform inside air temperature of 32 to 35 F can be maintained. Many such storage houses are to be found, principally in New York, Pennsylvania, Michigan and Wisconsin.
Storage houses should be insulated sufficiently to prevent freezing of the cabbage; for although slight freezing does little harm, hard freezing may cause considerable loss. Heaters are sometimes needed to prevent freezing of cabbage in common storage during severe cold weather.
Cabbage wilts quickly if held under too dry storage conditions; hence, the humidity should be high enough to keep the leaves fresh and turgid. Use of polyethylene liners or pallet covers to prevent desiccation can prove desirable under some storage conditions. Cabbage stored at 32 F has less decay when the relative humidity is maintained at or near saturation (98 to 100 %) than at 90 to 95 %.
Many growers now use pallet boxes as both field and storage containers so that there is no handling of the cabbage from the time of harvest until preparation for shipment or processing. Some of the larger storages stack these pallet boxes five high.
An increasing quantity of cabbage is now held in mechanically refrigerated storages. The storage life of late cabbage can be extended for several months if it is held in an atmosphere with 2.5 to 5 % oxygen and 2.5 to 5 % carbon dioxide. Cabbage should be handled carefully from field to storage, and only solid heads with no yellowing , decay, or mechanical injuries should be stored. Before the heads are stored, all loose leaves should be trimmed away; only three to six tight wrapper leaves should be left on the head. left on the head. Loose leaves interfere with ventilation between heads, and ventilation is essential for successful storage. Upon removal from storage, the heads should be trimmed again to remove loose and damaged leaves. Cabbage should not be stored with fruits emitting ethylene. Concentrations of 10 to 100 ppm of ethylene cause leaf abscission and loss of green color within 5 weeks.
The most common decays found in stored cabbage are watery soft rot, bacterial soft rot, gray mold rot, alternaria leaf spot, and black leaf speck.
PACKAGING
Cabbage in the northwest is most commonly packaged in 50 to 53-lb cartons containing 24 heads each. Other containers and weights used for cabbage are crates of 53 to 60 lb and 50-lb mesh sacks.