MUSTARD PRODUCTION
Types and Adaptation
There are three types of mustard that are commonly grown in
Western Canada which are yellow, brown and Oriental mustard.
Yellow Mustard belongs to the species Sinapis alba and is used to
produce milder table mustards and salad dressings. Brown and
Oriental mustard belong to the species Brassica juncea and are used
to produce “hot” table mustards and seasonings.
Mustard production is well suited for the brown and dark brown soils
of the Canadian prairies. Mustard is a cool season crop that will
germinate in cool soils. Mustard is quite frost tolerant, which, if
hardened, can withstand temperatures of less than –4C. Mustard has
a deep taproot that will enable it to weather short periods of
drought.
Field Selection
When growing mustard, field selection is very important. There is a
zero tolerance for genetically modified canola volunteers in mustard,
so mustard should not be grown in fields that have a history of
transgenic canola.
Effective weed control options are limited in mustard, so care should
be taken to avoid fields with infestations of difficult to control weeds
including cleavers, wild mustard, wild buckwheat, and thistles.
Fields that may contain herbicide residues that are damaging to mustard should also be avoided. Mustard is particularly sensitive to
many group 2 herbicides including: Pursuit, Odyssey, Everest, and Ally.
Seeding
Mustard should be seeded as early as possible in the spring, not only to avoid early fall frosts but also because early seeded crops
usually yield more than later seeded crops.
Like any small seeded crop mustard is very sensitive to seeding depth. Shallow seeding (0.5 to 1.0 inches) into a firm seedbed will help
establish a healthy plant stand. When seeding to moisture on a lighter soil, seeding depth should not exceed 1.5 inches. A good
target plant stand for mustard is 7-10 plants/foot however mustard will compensate very well for wide variations in plant populations
with similar yields being achieved with plant stands ranging from 3-20 plants/foot.
When choosing a seeding rate to achieve the optimum plant stand, it is important to remember that yellow mustard is approximately
twice the seed size of brown and Oriental. (yellow mustard “thousand kernel” weight is approximately 5.5g/1000 kernel, brown
mustard is 2.4g/1000 kernel and Oriental mustard is 2.8 g/1000 kernels). As a rough guideline a seeding rate of 7-10 lbs/acre of yellow
mustard and 4-6 lbs/acre for brown and Oriental is usual suitable. Higher seeding rates should be considered when seeding conditions
are less than optimal.
Fertility
Mustard will respond well to good fertility, if other growing conditions are good. Mustard is sensitive to seed placed fertilizer. When
considering seed placed fertilizer it should not exceed rates safe for other oilseeds, like canola.
To accurately determine the fertility requirements of a crop of mustard, you must know the fertility present in the soil; soil testing is
the best way to determine this. You also must make a realistic estimate as to what the yield will be. Mustard uses approximately:
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2-3 lbs of nitrogen/bushel ;
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1-1.5 lb/ of phosphate/bushel; and,
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0.5 lbs of sulfur /bushel.
A general recommendation for a 20-bushel crop of mustard would be:
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40 lbs/acre nitrogen,
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15-20 lbs/acre phosphate; and ,
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10 lbs/acre of sulfur.
Insects
Like any other crop, mustard is sensitive to insect feeding. However because of the presence of natural toxins called alkaloids,
mustard is more resistant to insect feeding than many other crops.
Insects that can damage mustard include flea beetles, cutworms, grasshoppers, diamond back moth, armyworms, lygus bugs and
cabbage seedpod weevils.
Mustard should be closely monitored in the spring for cutworm feeding. If feeding damage occurs insecticide application may be
warranted.
Flea beetles can cause damage to mustard, so it is wise to use a registered seed treatment that contains an insecticide that will control
flea beetles on seedling mustard. If seedling leaf damage exceeds 50% then a foliar insecticide should be applied.
Unlike canola, lygus bugs do not generally do a lot of damage to yellow mustard, so control is not warranted even if lygus bugs are
present in the crop. Brown and Oriental mustard can be damaged by lygus bugs, but thresholds although not established seem about
50% higher than for canola.
Grasshoppers can be devastating to mustard. If present in high enough numbers insecticide application may be required.
Diamond back moths will feed on mustard and control may be warranted if numbers exceed the economic thresholds of 30larvae/square foot.
Bertha army worms will also feed on mustard, control may be warranted if numbers exceed the economic threshold of 3 larvae/square
foot.
Seedpod weevils will feed on mustard although they do prefer canola. Control is generally not warranted on yellow mustard, but may
be required on brown or Oriental mustard.
Weeds
Weed control options are very limited in mustard so it is wise to choose
relatively weed free fields in which to grow mustard.
Weeds that are of particular concern when growing mustard include volunteer
genetically modified canola, as there is a zero tolerance for any GMO canola
seed in mustard. Other weeds that are difficult to control in tame mustard
include wild mustard, thistles, buckwheat, smartweed, kochia and flax.
Note: Use only registered pesticides on mustard and check with the buyer of
the mustard for any additional restrictions that may be in place in regards to
pesticide use.
Do not apply pre-harvest glyphosate to mustard, as this is not acceptable to
most buyers.
Harvest
Yellow mustard is resistant to shattering so it is usually straight cut combined. It
should be threshed when the moisture content is less than 9.5%. If yellow
mustard is to be swathed then at least 75% of the seeds should have turned
yellow and the remaining 25% should be firm and pale green. Mustard does
not ripen in the swath like canola, so care should be taken not to swath to soon.
The result of swathing too soon will be too many green seeds.
Brown and Oriental mustard will change color more in the swath than yellow mustard. They can be swathed when the moisture
content of the grain has dropped to less than 25%. In the case of Oriental mustard, by this time usually 75% of the seed will have
turned yellow. With brown mustard at least 60% of the seeds should be brownish red in color.
When swathing the use of a swath roller to compact the swath will minimize the amount of loss from wind. In windy regions, cutting
higher and then pushing the swath further into the stubble may minimize wind loss. However, this must be balanced against the
difficulty in picking up a short swath.
Mustard is easily cracked when threshed so combine cylinder speed should be reduced as low as possible (400-800 RPM). Tolerance
for cracked mustard seed is very low. For grades 1 and 2, the tolerance for cracked seed is less than 1.5%. To check for cracked
mustard seed, pour some mustard seeds against your forearm. The cracked seed will tend to stick to the hairs on your arm.