Note Number: AG0499
Published: August 1997
Updated: November 2009
Reviewed: August 2013
The cabbage (Brassica oleracea var capitata) belongs to the family Cruciferae and is related to cauliflower, broccoli and brussel sprouts. Cabbages are grown 12 months of the year in Victoria and production is concentrated in southern districts. Cabbages are grown for both fresh market and for processing.
Cool moist weather produces the best quality heads. Consequently cabbages can be grown under a wide range of conditions and are adaptable to most production areas around the state. They are grown all year round in southern Victoria but in the hot northern districts, quality crops can only be produced from late autumn to early spring. Where winter snows are often recorded, such as in parts of the Central Highlands of Victoria, crops are limited to the late summer to early winter markets.
Cabbages grow on a wide range of soil types ranging from light sand to heavier clays. Soils with high organic matter give the best yields. Apply lime early in soil preparation if the soil pH is less than 6.0. Do not over-lime, otherwise the essential element manganese may become unavailable to plants.
Heavy soils in suitable rainfall areas in southern Victoria can produce good late autumn and winter crops with little or no irrigation. Good drainage is important and in high-rainfall areas, crops are grown on raised beds to improve drainage and, for this reason, when working the soil, keep it in the raised position at all times.
Soil pH should be in the range of 6-6.5 for actual growth and a high pH is important for clubroot control.
Cabbages can be divided into three main groups: ballhead (or roundhead), conical and the large drumhead types. There is a wide range of cultivars available with many suited for production at particular times of the year whereas others can nearly be grown year round. Red cabbages are also grown but the major production is of green cabbage.
There is a wide range of varieties and particularly for the newer cultivars, their suitability for a particular area can only be judged by growing them in the region.
Some cultivars and their appropriate production time slots include:
Late spring to winter - Green Coronet, Kameron, Red Rookie.
Late summer to autumn - Red Ball, Beauty, Stariha.
Summer to winter - Grand Slam.
Autumn to winter - Red Ranger, Neptune. Winter to spring - Ballhead, Greengold, Winterhead, Terrific.
The variety Savoy King is suited to year round production in southern production areas whereas most of the other main varieties are suited to more specific production times.
These are just some of the cultivars available but it includes most of the major varieties grown. For more information on the range of cultivars and new releases seed companies should be contacted.
Crops are usually grown from seedlings planted with the aid of transplanting machines. The seedlings are most often purchased from commercial nurseries where they have been grown in cell-trays. Some growers produce their own seedlings. Less commonly, growers produce their own bare-rooted seedlings in sterilised soil beds.
If seedlings are being obtained from a commercial nursery they should be ordered in advance for it can take up to 6 to 8 weeks from seeding before speedlings are ready for transplanting.
The advantage of using cell grown seedlings is that they should be produced under conditions of even growth and strict disease control. A sterilised potting mix and seedling tray are used which should eliminate the likelihood of soil borne diseases such as blackleg, clubroot and soil borne nematodes.
Hot-water treatment of seed before sowing also helps to reduce the incidence of seed borne diseases such as blackleg, blackrot, ringspot, alternaria leaf spot and bacterial leaf spot. Temperature control is critical for not hot enough and the disease will not be destroyed and too hot will damage or kill the seed.
Crops can be grown by direct seeding but seeds should be planted around 4 weeks earlier than transplants to allow for germination and match growth through to maturity.
Cabbages require large amounts of fertiliser but are not quite as demanding as cauliflowers and generally a base dressing and one or two side dressings are applied. The amount and frequency of fertiliser application depends on soil type and requirements will also be affected by previous management and current soil fertility. A soil test can be useful in determining the availability of nutrients and fertiliser requirements. Cabbages also benefit from high levels of organic matter in the soil.
As a guide base fertiliser requirements are in the order 500 to 900 kg/ha of 8:11:10 or 800 to 1200 kg/ha of a similar fertiliser such as 6:6:6 or equivalent. Banding the fertiliser under the rows will allow fertiliser rates to be reduced. If fowl manure (deep litter) is available it should be applied at around 22 m 3 /ha and fertiliser rates can be reduced by around one third. At least one side dressing before head formation is required and on lighter soils crops would benefit from a second side dressing. Side dressings can range from 200 to 400 kg/ha of 20:0:16 or similar, drilled into the soil, or a combination of urea and potassium nitrate to apply similar levels of nitrogen and potassium.
Since growth rates and release of nutrients from the soil is slower in winter higher rates of fertiliser will be required to compensate. Trace elements such as molybdenum are very important and can be incorporated with the base dressing or added later as foliar sprays.
Farmers should be aware of the potential dangers of using phosphatic fertilisers with high levels of cadmium. Research has shown that the use of phosphatic fertilisers which contain the heavy metal cadmium as a contaminant can increase cadmium levels in both soil and potatoes. There are legal maximum levels of cadmium allowable for vegetables sold in Australia, however no violations have been recorded for cabbages as a result of survey investigations. Fertilisers containing cadmium in excess of 1 mg/kg are required to state the following warning:
"WARNING––this product contains cadmium. Continued use of this product in agricultural situations may lead to residue levels in plant and animal products in excess of the maximum level specified by the Australia New Zealand Food Standards Code and the accumulation of cadmium in soils."
It is in the grower's and consumer's interests to minimise the addition of cadmium to soils and agricultural produce. Growers should consult fertiliser suppliers or manufacturers for advice on the cadmium levels of fertilisers they are considering using. There are a number of low cadmium horticultural fertilisers marketed today. These have lower levels of cadmium than some superphosphate and other fertilisers.
Common trace element deficiencies
Trace element deficiencies can be affected by soil pH and it is important to monitor soil acidity. In marginal situations, symptoms of deficiencies are often seen when conditions are dry, but may not appear if plants are kept well watered. These deficiencies lead to characteristic deformations of the leaves.
Molybdenum deficiency is often induced by soil acidic reactions and the main symptom of the disorder is the malformed leaves, which are narrow, twisted, and hooked, if the deficiency is severe, resulting in a disorder called "whiptail" in cauliflower. A spray of ammonium or sodium molybdate should be applied.
An induced manganese deficiency may occur if too much lime is applied. The main symptom is severe mottling between veins, which retain their normal colour. This may be corrected by applying manganese sulphate (5 kg per 1000L of water). Several applications may be needed and a wetting agent should be used.
Potassium deficiency which is also known as leaf scorch or marginal leaf burn can be corrected by applying muriate of potash at between 200 to 300 kg per ha.
Cabbages require regular irrigation to ensure rapid growth and evenness of maturity. Cabbages grown on beds will require more irrigation than those grown on the flat. Soil type and weather will also influence requirements.
The main pests of cabbage crops are aphids, cabbage white butterfly and cabbage moth (diamond back moth) which can all seriously damage crops. Cabbage moth is a major problem due to its ability to develop resistance to a number of pesticides and if it is likely to be a problem a control strategy should be implemented.
A strategy for diamond back moth control can be obtained from Department of Environment and Primary Industries and is based on alternating chemical groups. Good farm hygiene is also important in pest control. Rapid removal of old crop residues is important for otherwise these will act as a reservoir for pests and allow pest populations to build up making control more difficult.
Chemical users must ensure they read and understand all sections of the chemical label prior to use.
There are a range of fungal, bacterial and virus diseases which may affect cauliflower crops. Some of the main diseases include black rot and other leaf spots, downy mildew, sclerotinia, ring spot, blackleg and clubroot.
Clubroot, a soil borne disease, is a major problem in many districts. Crop rotation combined with soil liming and strategic planting should be used as a measure to reduce the incidence of this disease.
Weed control problems vary with the season and will depend upon, the weed control history of the paddock, the weeds to be controlled and the time of the year.
There are several herbicides registered to control weeds in cabbages. For the registration status of these products, please refer to Australian Pesticides and Veterinary Medicines Authority, your chemical reseller or your local chemical standards officer. Ensure you meet the relevant Maximum Residue Limits (MRLs) for the chemical in the end market, be it domestic or export.
Chemical users must ensure they read and understand all sections of the chemical label prior to use.
From 16 000 to 25 000 cabbages are planted per ha; most plantings are of 20 000 plants per ha. The in-row spacing ranges from 400 mm to 600 mm, and from 900 mm to 1100 mm between rows, depending on the system of culture used and the cultivar grown.
Cabbages are sold by quantity, rarely by weight and a unit of measure is the dec (10 heads).
Expected average yields range from 1300 to 2000 dec per ha.
Weight and size may only be important when the cabbage is to be sold for processing. Most processors prefer large, heavy cabbages.
A cabbage is mature when the head is firm to touch. Heads firm gradually until they become hard. If left too long the heads can split and become unmarketable.
Cutting is usually carried out in the morning and heads are cut so that a few wrapper leaves are present to protect the heart.
Cabbages are either marketed by the dec (10 heads) with full leaf or may be trimmed and packed in cartons, crates, or bulk bins.
For information relating to the safe and appropriate use of chemicals, including management of chemical residues and licensing requirements, contact us and ask to speak to your local chemical standards officer or visit our Chemical use page.
This Agnote was developed by Rob Dimsey Farm Services Victoria in August 1997.
It was reviewed by Rob Dimsey, Farm Services Victoria in November 2009 and August 2013.