What is crambe used for?
The oil extracted from Crambe is rich in erucic acid from which erucamide is derived which is used primarily in the plastics industry as a slip-agent (i.e. to coat plastics, such as bags and bottle tops, to stop them sticking together). Crambe seed contains 35% oil, of which 56–58% is erucic acid. The potential market for erucic acid oils in Europe is currently thought to be in excess of 70,000 tonnes per annum, most of which could be satis fi ed by Crambe. Crambe oil is similar in its composition to that of High Erucic Acid Rape (HEAR), however the oil is more favourable due to higher concentrations of erucic acid and better colour characteristics.
Where can it be grown?
Crambe has only been grown in the UK since 2001; however production has increased year on year. Crambe is also grown successfully in Italy, the Netherlands, USA, New Zealand and Australia. Crambe can be grown on a wide range of soil types from sands to heavy clays, although soil structure and moisture availability in the early stages of growth determine crop productivity. Crambe is unrelated to other major arable crops in the UK and therefore does not pose a problem in existing crop rotations, where it is most likely to replace oilseed rape or alternative break crops. It does not cross-pollinate with oilseed rape, therefore separation distances are not required, as they are between conventional and high erucic acid rape. To avoid problems with volunteers, Crambe should not be grown within four years of oilseed rape.
Crambe, as a flower is almost unmistakeable, the plant will cover itself in a mass of frothy, foam-like flowers which look rather fragile, but are exceptionally sweet-scented, according to research undertaken by EbeeHQ, this helps attract these blooms to nearby colonies of bees and surrounding beehives This wonderful Cordifolia species provides an exceptional service to local wildlife, and being deep-rooted, it is particularly drought tolerant, and therefore grows without need for much human intervention or assistance.
Crambe is a spring sown annual, attaining 1m in height and produces a strong tap-root and visible small white flowers. It has better drought tolerance than oilseed rape and a particularly short growing season.
Good establishment is key to successful production of crambe. Crambe is a small seed, so a fi rm moist seedbed will help to encourage even establishment. As Crambe seedlings are sensitive to frost sowing is carried out from early April through to mid-May, after risk of frost has passed. A stale seedbed approach can help weed control. Using a conventional cereal drill Crambe should be sown in rows 12 -15cm apart, to a depth of 1.25cm. A target population of 120–150 plants/m2 is thought to be optimum density to achieve maximum yields. This can typically be achieved at a sowing rate of between 15–20kg/ha. Initial growth phases of Crambe are slow and weed control is critical. Early crops drilled into moist seedbeds may prove more competitive with weeds than those drilled in dry conditions.
Crambe requires moderate inputs, similar to oilseed rape, in order to maximise productivity.
Nutrient demands are similar to that of spring oilseed rape. 150kgN/ha may be applied to seedbeds or post emergence, or split between the two if leaching is an issue on lighter sandy land. A response to sulphur is possible in situations similar to that seen for responsive oilseed rape crops. Maintenance dressings of P and K should be suffi cient, no yield responses are seen with additional applications.
Crambe is indeterminate in nature, so crop maturity can be uneven. Harvest will occur from late July-September depending on sowing date (generally 100 day growing cycle). The crop is versatile and can be desiccated, swathed and combined or direct combined, depending on area, uniformity of maturity, weather conditions, equipment availability and weed density. Pre-harvest swathing or desiccation is favoured in crops with poor uniformity, when 50% of seeds have turned brown. The crop can then be gathered by combine 7–10 days later. In a uniformly mature crop direct combining is the best option to minimise costs
Crambe yields currently average around 2–2.5t/ha. Contract price is currently around £180/tonne plus oil bonus. Contracts include bonus/deductions for oil content above/below 35%. Returns are comparable to cereals and oilseeds; however the value as a break crop must be taken into consideration as Crambe has a positive effect on yields when followed by cereals.
Crambe should be dried to 9% moisture and cleaned to 2% admixture prior to storage. Due to the lightweight yet bulky nature of the crop, suffi cient storage area should be allocated prior to harvest.
For more information on Crambe, please refer to the NNFCC’s document factsheet on the crop : NNFCC Crambe Factsheet