Abu Dhabi Farmers' Service Centre – open-field
vegetable production guide
Growing cabbage for profit and sustainability
2014-2015 Season Guidelines
Introduction
Cabbage (Brassica oleraceae) is a biennial plant belonging to the Cruciferae family. They are popular traditional vegetables in the UAE
with several varieties grown for the local markets. The types favored by supermarkets are red, green or white fully round shaped
cabbage. Flat varieties tend to go to wholesalers. Careful selection of varieties, adoption of appropriate technology and good
management of cabbage crops throughout the production cycle allow growers to maximize profits.
This guide outlines the key practices essential for producing high yields of good quality cabbages under UAE growing conditions over
the growing season to meet market demands.
Growing season
Sowing: September to mid-January
Transplanting: October to mid-February
Harvest period: December to mid-May
Table 1: Cabbage growing season
Month
Sowing
Transplanting
Harvest
Aug
Sep
Oct
Nov
Dec
Jan
Feb
Mar
Apr
May
Jun
Growing period
Nursery sowing to transplant: 4 weeks
Transplant to harvest: 10 weeks
Total crop cycle: 14 – 16 weeks
Table 2: Cabbage growing period
Week
Stage
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25
S
T
H H H
Key to colours and symbols: S Sowing
T Transplanting H Harvesting
Varieties
Varietal selection is important for the success of your crop. Varieties selected should suit local climatic conditions, have good pest and
disease resistance and meet market needs. The green round and white round varieties attract the best market prices in the UAE.
Communicate with your marketer and seed supplier to determine the most suitable variety for UAE growing conditions and that gives
you best returns.
Irrigation layout, plant density and expected yield
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Abu Dhabi Farmers' Service Centre – open-field
vegetable production guide
In Abu Dhabi cabbages have traditionally been planted with a between row plant spacing of 90 cm resulting in a per donum plant
density of 4,400 with a typical yield of 5,000 kg (Table 3). Yield can be increased to 9,000 kg using new pressure compensated inline
drip irrigation systems and higher plant density. Using the high density planting arrangement, cabbage seedlings should be planted in
40 cm rows and within row plant spacing of 40 cm.
Table 3: Plant arrangement and density
Plant spacing
Between
rows
(cm)
Plant arrangement
Recommended
High density planting
Not recommended
Traditional planting
90
Within
rows
(cm)
Drip line spacing
Between
lines
(cm)
40
40
40
50
90
50
Figure1: Correct spacing for high density cabbage
Within
lines
(cm)
40
Plant density
Layout detail
Beds of 2
rows x 40 cm
spacing with
pathway of 60
cm between
beds
Cluster of 2
plants per
dripper
4,400
Number of
plants/
donum
Potential
marketable
yield
(kg/
donum)
5,000
9,000
5,000
Figure2: As the crop matures full ground cover is achieved
improving water use efficiency
Soil analysis and water quality requirements
Cabbages are moderately sensitive to soil salinity. At the nursery stage and soon after transplanting, it is recommended that irrigation
water should not exceed 1.2 dS/m (1,150 ppm). Prior to field preparation, soil and water samples should be taken and sent for analysis.
Once plants are fully established, a water salinity of up to 1.9 dS/m (1,220 ppm) can be used to grow the crop provided leaching
requirements are strictly followed. Irrigation water salinity levels higher than 4.6 dS/m (3,000 ppm) will severely restrict growth and
a 50% yield loss can be expected. Under salt stress, cabbage heads are generally more compact, and leaves are fleshier than under
nonsaline conditions. Your local ADFSC extension engineer can assist you with soil and water sampling techniques and help interpret
results from the lab to grow the crop successfully.
Land preparation and pre-planting fertilising
Thoroughly cultivate the area to be planted four weeks prior to transplanting. Apply pre-planting fertiliser and well composted manure
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Abu Dhabi Farmers' Service Centre – open-field
vegetable production guide
in a 30cm wide band along each drip line and mix thoroughly into the top 10cm to 15cm of the soil along this band. The fertilisers that
should be incorporated into the soil at least two weeks prior to transplanting are shown in Table 4 below.
Table 4: Pre-planting fertilisers
Pre-plant
Composted manure (kg/donum)
Triple super phosphate
(kg/donum)
Total application
2,500
50
Pre and post-plant fertiliser applications provided are only a guideline. Fertiliser recommendations should be based on soil and
irrigation water analyses and experience of soil conditions in your local area. Contact your ADFSC extension engineer for assistance
with testing water and soil on your farm and formulating a fertiliser program.
Cabbage benefit from high levels of organic matter. The composted manure provides organic matter to the soil to help with retention
of irrigation water and nutrients for a strong healthy root system. Organic material must be thoroughly composted to avoid introducing
weed seeds, pests, diseases and causing seedling root burn from high temperatures produced during the composting process.
Installation of new irrigation lines
Existing irrigation systems can be adapted to the new layout by attaching new drip lines at the required spacing to the existing
underground sub-mains or lateral water pipes. Existing outlets that do not align with the new spacing should be blocked off. In some
situations farmers may choose to install new sub-mains or lateral pipes to facilitate the new drip line layout. Always test the irrigation
system and dripper prior to transplanting to ensure all drippers are working properly. This is ideally done as part of the pre-planting
weed control.
Cabbage nursery
Sowing cabbages in a well-managed field nursery has the following advantages over direct sowing in the field:
 A more favourable and even germination
 A protected location on the farm under Agrile row cover provides a good seedling environment and minimises the risk of virus
infections through whitefly infestations
 Improved irrigation control and crop monitoring during the sensitive germination and seedling stage
 Minimised irrigation water use and salt accumulation in the field for the nursery period between 3 and 4 weeks. This effectively
reduces irrigation water consumption, potential salt build-up and the leaching of nutrients from the root zone
 Selection of strong evenly sized seedlings for transplanting and good production
Cabbage nursery requirements are given in Table 5 as follows:
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Abu Dhabi Farmers' Service Centre – open-field
vegetable production guide
Table 5: Cabbage nursery planting and seed requirements
Seed requirements
Number of
seeds/g
Number of g/ donum
(with 20% additional
allowance for germination and replacements)
RecomTradimended
tional
plant
plant
spacing
spacing
280 to 380
16 to 22
Number of plants/donum
Crop
Cabbage
Recommended sowing method
Nursery
Sowing
depth
(mm)
5 to 10
In recommended
spacing
In traditional spacing
5,000
4,400
14 to 19
Cabbage seedlings can be produced in the ground in nursery beds, in flat-cell trays or in Jiffy pots. Potting mix should be preferably
mixed with water before packing the mix into the trays or Jiffy pots. When seeds are started in cell trays, a good commercial potting
mix should be used to improve water and nutrient availability, provide correct aeration and minimise pests and diseases. In the field,
cabbage nurseries can be established using a good potting mix that provides appropriate soil conditioning. An Agrile row cover should
be used to protect seeds from excessive surface temperatures and disease carrying insects. Good aeration, temperatures not
exceeding 30⁰C and adequate moisture are necessary to encourage rapid even germination of seeds and growth of seedlings. Over
watering will result in seed death from lack of oxygen leading to poor germination and should be avoided. Production of cabbage
seedlings in ground nurseries is generally not recommended as bare root transplants are slow to establish in the field, lead to higher
seedling mortality and reduce yield. Moreover, it is difficult to maintain a root ball during the digging out process as the soil is light
and friable resulting in bare root seedlings for transplanting.
The nursery should be observed twice daily to make sure that optimum conditions are maintained during the germination and seedling
development. Soon after emergence, the seedling should be exposed to adequate sunlight to support good strong growth. Early
detection of problems allows a rapid response when extra water, nutrient or pesticide applications may be required. Seedlings are
ready for transplanting in approximately 4 weeks after sowing.
Seedlings can be hardened to better prepare them for transplanting, as follows:
 Stop fertiliser applications seven days before transplanting.
 Reduce irrigation to stress the seedlings two days before transplanting.
 Resume normal irrigation the day before transplanting.
 Transplant the seedlings in the cooler part of the morning or evening.
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Abu Dhabi Farmers' Service Centre – open-field
vegetable production guide
Figure3: White cabbage seedlings under Agrile cover
Figure4: Red cabbage seedlings
It is important to minimise stress on the seedlings by keeping them out of direct sunlight and not letting them dry out.
ADFSC extension engineers can provide advice about the best approach for nurseries on your farm.
Growing stage
Transplanting
Cabbage seedlings are transplanted into prepared rows at 40cm spacing between plants within the rows. Whether seedlings to be
transplanted are lifted from the nursery bed, from seedling trays or Jiffy pots it is important that the roots are not disturbed and the
soil surrounding the roots maintained. Bare root transplants are discouraged as they will take longer to establish in the field.
Management of the young plants is easier than with bare-rooted seedlings.
Crop nutrition and application of soluble fertilisers through irrigation (fertigation)
Weekly or more frequent fertigation is recommended according to the following schedule:
Table 6: Recommended weekly rates for fertigation fertiliser (kg/donum) and trace element application for UAE sands
Growth stages in
weeks after transplanting
Ammonium
sulphate
Potassium
nitrate
Week 1
Week 2
Week 3
Week 4
Week 5
Week 6
Week 7
Week 8
Week 9
Week 10
Total
3.0
3.0
3.0
4.0
7.0
7.0
7.0
7.0
7.0
2.0
50.0
3.0
3.0
3.0
5.0
5.0
5.0
5.0
5.0
1.0
35.0
Magnesium
sulphate
0.5
1.0
1.0
1.0
1.0
1.0
0.5
6.0
Trace element mix
Chelated Fe
(EDDHA)
0.2
0.2
0.2
0.2
0.2
0.2
0.2
0.2
0.2
0.2
0.2
0.2
0.2
0.2
0.2
0.2
0.2
0.2
2.0
2.0
Notes on fertigation
1. Fertigation should begin on the first week after transplanting
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Abu Dhabi Farmers' Service Centre – open-field
vegetable production guide
2.
3.
4.
Depending on the soil and water analyses it may be necessary to supply other chelated trace elements.
Continue irrigation for 5 minutes after fertigation to flush the system.
More frequent fertigation can be adopted and the fertiliser dosage should be adjusted accordingly
The above schedule of weekly applications (Table 6) is only a guideline for the sandy soils typically found on Abu Dhabi farms. The
exact fertiliser recommendations should be based on soil fertility levels and irrigation water conditions in your area. Contact your
ADFSC extension engineer for assistance with testing water and soil on your farm.
Weekly or more frequent fertigation ensures that nutrient levels are maintained in the root zone of the crop throughout the important
growing and production periods.
These recommendations are based on good irrigation practices. Excessive irrigation will leach nutrients away from the root zone.
Crop water requirements
Young cabbage transplants or seedlings have a lower water requirement. However, water requirement increases rapidly as complete
canopy cover and head development occurs. Irrigation must be closely monitored to ensure soil moisture remains even in the beds
during the cropping period. It is particularly important in the days following transplanting when seedlings are establishing new root
systems. Excessive irrigation promotes root rot and results in leaching of nutrients away from the root zone. Supplying water in equal
amounts throughout the season prevents cracking of the heads.
Application of soluble fertiliser as fertigation can be carried out during a normal irrigation. Continue irrigation for 5 minutes after
fertigation to flush the system.
Figure5: Achieving full ground cover with high density
red cabbage
Plant protection
Many pest and disease problems can be avoided through Integrated Pest Management (IPM) procedures.
The following will help to ensure any pests and diseases in your cabbage crop remain below the economic threshold and swift action
is taken should they become a problem.
Use of pest resistant varieties
This ensures your crop has natural resistance to pests and diseases, minimising the need for expensive chemical control.
Row covering
These should be put up immediately after transplanting and left up for 10 – 15 days. They protect your crop from numerous insect
pests, such as caterpillars, aphids, leafhoppers, leaf miners, beetles and white-flies.
Crop rotation
Do not plant cabbage more than once every 3 – 4 years in the same field. This will minimise the risk of fungal and bacterial diseases
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Abu Dhabi Farmers' Service Centre – open-field
vegetable production guide
such as bacterial black rot and fungal diseases such as downy mildew, powdery mildew, white rot and damping off.
Soil solarisation
This should be carried out each summer prior to planting to help control soil borne pathogens, soil insects, weeds and root-knot
nematodes.
Companion crops
Planting corn and squash as a trap crop around the borders of your cabbage crop keeps aphids away, reducing the incidence of
turnip mosaic virus.
Traps
Placing yellow and blue sticky traps and pheromone traps around your cabbage crop will help control whitefly, leaf miners and
caterpillars.
Removing and correctly destroying all crop residues immediately after harvest
This helps prevent last season’s pests re-infecting your new crop and will help to control fungal and bacterial diseases, caterpillars,
aphids and beetles.
Good weed management
Irrigate the beds prior to transplanting to stimulate germination of weed seeds. Remove all weeds prior to transplanting.
Following planting, the field should be monitored regularly and kept free of weeds. Remove weeds by hand at early growth stages of
cabbage and before canopy covers over.
Crop monitoring
Cabbage crops should be monitored for pests and diseases every week. This is especially important during the early stages of growth
when cabbages are susceptible to pests and diseases. Consistent monitoring enables a swift and effective response should an
outbreak occur, which will minimise crop damage and expense.
Thorough composting of all organic matter
All manure put on the crop should be thoroughly composted to prevent pest and disease outbreaks.
In the event of a pest or disease outbreak please contact your nearest ADFSC extension engineer to correctly identify the pest or
disease and provide recommended control measures.
Harvest stage
Pre-harvest interval (PHI)
Pre-harvest interval is the time between the last pesticide application and harvests of the treated crop. The PHI must be adhered to
for all crops. Failure to adhere to the PHI will result in pesticide residues in the harvested produce, which will render the crop unfit for
human consumption and for sale. It is illegal to sell crops where the PHI has not been adhered to. For further advice on harvest
intervals please contact your local ADFSC extension engineer.
Field Hygiene during harvest
Good field hygiene is required to ensure your crop is free of contaminants. This is essential for it to be sold in the market. Good field
hygiene practices must always be adhered to when harvesting fresh vegetables.
Crop maturity, handling and storage
Cabbages should be harvested during the cooler parts of the day to avoid heat and sun damage. To ensure best prices, the base should
be neatly trimmed with a clean, sharp instrument to prevent from tearing and rotting. Cutting blades should be regularly cleaned to
prevent the spread of disease. For field packed cabbages, the leaves should be stripped away to present a neat and clean product with
the shape typical of the variety. For best prices, consult the most recent marketing specifications available from the ADFSC for size
requirements. Smaller size cabbages can be more profitable than larger sized ones.
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Abu Dhabi Farmers' Service Centre – open-field
vegetable production guide
Cabbages are prone to damage which reduces shelf-life and saleability of the product. They must be handled with care and never be
thrown or dropped.
Harvested cabbage should be moved from the field to a cool shaded location for short term storage. They must never be left exposed
to direct sun. This is especially important during late season harvesting when air temperatures and intensity of the midday sun will
dramatically reduce quality.
Cabbages should be free from mechanical damage and be of uniform shape and size in each tray.
Cabbages should be packed carefully to reduce risk of damage in transit. Crates must be stacked safely and securely so they are not
resting on the produce beneath.
Grading
To ensure cabbages receive the best price, they must be graded according to the current ADFSC specifications. These can be obtained
from your local procurement officer.
Figure6: White cabbage ready for harvest
Figure7: Red cabbage ready for harvest
For further information and advice:
Contact your local ADFSC office for professional advice from our experienced team of extension engineers.
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