Mustard is a very quick growing green manure, that can be sown from March – September and has a growing period of 1-2 months and can reach 60-90cm. The half hardy annual grows on most soil types and produces large volumes of green matter and residual fibre which is particularly good for those soils that lack organic matter it helps to improve soil texture and moisture retention.
After 4-8 weeks of growth chop down the plants and cultivate into the top few inches of your soil. On sandy ground let mustard reach 40cm in height or wait for the first flowers to appear before digging in. This will produce more fibrous plant matter which can help very free draining soils retain more moisture and nutrients. It isn’t a nitrogen fixer though but is still a very worthwhile leafy green manure.
As part of the brassica family, repeated sowings and digging in of the mustard at 4-8 week intervals may help to clear infected land of club-root. Mustard is part of the brassica family and it will activate the dormant spores of this fungal disease, and will allow the grower to break its life-cycle as the plants are prematurely destroyed. An excellent plus, as club-root disease can remain dormant in the ground for up to 20 years but this is not a quick fix and it will take a number of repeated sowings.
As it is part of the brassica family don’t use mustard in crop rotation plan before sowing a brassica crop as this increases the likelihood of diseases.
Another control is that if allowed to fully mature it can clear a site of wireworms- these insects can devastate a crop of potatoes. Wireworms feed on the dug in and decomposing mustard crop, they mature quickly and fly off as beetles to lay in pasture, so the cultivated area is now clear.
The seeds produced are used to make the yellow mustard sauce that Americans use on their hotdogs.
