Growing Faba Bean

Faba bean is best adapted to the more moist agriculture areas of Saskatchewan and does best under relatively cool growing conditions. Hot, dry spells will result in wilting of the plants and may reduce seed set. Faba bean should be grown with caution in the brown soil zones and on drought prone, light-textured soils unless irrigation is available, as faba bean responds very well to irrigation.

Pulse crop adaptation trials conducted at seven locations in Saskatchewan showed best faba bean yields were obtained in cool and or wet locations.

• Thin seedling stands often occurred under dry conditions.
• It appeared that the crop was able to compensate for poor stand establishment if moisture conditions improved throughout the season.
• Faba bean remained vegetative for 54 days and reproductive for 58 days and used 39 cm of water, when data were averaged across the seven sites.

Faba bean plots yielded almost 6.7 tonne/ha (100 bu. / acre) in ideal growing conditions. The long period of reproductive growth appeared to limit yield, indicating that an earlier seeding date or earlier maturing cultivar may improve faba bean adaptability to Saskatchewan. Current varietal development for small-seeded types is also focused on early maturity.

Faba bean should not be grown on the same field more than once every four years and should not follow oilseeds or other legume crops in the rotation because of the potential increase in soil-borne diseases.

Planting faba bean on cold, poorly drained soils should be avoided to decrease the development of seedling diseases and root rots. Faba bean doesn't tolerate salt affected soils, but is more tolerant of temporary flooding compared to lentil, pea or dry bean.

Rotational Considerations

Faba bean is an excellent nitrogen fixer decreasing need for nitrogen fertilizer. A major benefit of rotating pulse crops, such as faba bean, with cereal crops is the interruption of pest cycles. Most cereal diseases don't affect pulse crops. Soil-borne root rots in continuous cereal systems may cause average yield losses up to 10 percent.

Grasshoppers selectively consume faba bean, so the crop should not be planted in fields with a high risk of grasshoppers. Faba bean isn't a host for wheat midge or wheat-stem sawfly making it an excellent rotational crop option for wheat growers. Highly fertile soils, such as fields with high levels of available nitrogen, may produce excess vegetative growth at the expense of seed production.

Faba bean is a poor competitor with weeds, and selection of a clean field is important. Perennial weeds, such as Canada thistle and perennial sow-thistle, should be controlled in the years prior to faba bean production.

Faba bean is susceptible to the soil residues of some herbicides used in previous years. It is important to record herbicide use each year and to avoid seeding this crop in fields with the potential for herbicide residue.

Those herbicides that have label recommendations for faba bean re-cropping are listed in the current Guide to Crop Protection; see "Re-cropping Restrictions for Residual Herbicides".

Other herbicides may have the potential to leave soil residues that may injure faba bean, but don't have label recommendations. If you suspect potential herbicide residual problems, please check with the manufacturer for more information.

In these cases a successful bioassay should be conducted before faba bean planting is attempted. A bioassay is the growing of a test strip of a desired crop in the field with potential residue to determine safety of that crop. This may also be conducted in the lab with soil collected from the field. The Alberta Research Council conducts these tests.

For more information call Alberta Research Council at 780-632-8436.

Note - Drought conditions may extend carryover of residual herbicides by an additional season for each drought year experienced.

The Ministry of Agriculture publication, Guide to Crop Protection contains more information about herbicides and their soil residual properties.

Irrigation

Faba bean is very well adapted to production under irrigation. Agronomy of irrigated faba bean is similar to dry land production. Yields can be much higher than dry land production; however, special attention must be paid to prevent losses due to diseases, such as botrytis and ascochyta.

Inoculation

Faba bean is a legume and is able to provide a significant level of nitrogen from the soil air using a symbiotic relationship with Rhizobium bacteria. Faba bean is the most efficient nitrogen fixer of the pulse crops grown in Western Canada. For nitrogen fixation to occur, the seed or soil must be inoculated with the appropriate strain of Rhizobium.

The Rhizobium bacteria enter the root hairs and induce nodule formation.

• The plant provides energy for the bacteria living inside the nodules; and, in return,
• The bacteria convert atmospheric nitrogen into plant-useable forms.

Maximum benefit is derived if the supply of available soil nitrogen is low and the soil moisture and temperature levels are adequate for normal seedling development from the time of seeding until seedlings are well established.

High available soil nitrogen levels (amounts over 55 kg nitrogen/ha) delay the onset of nodulation and inhibit nitrogen fixation since the faba bean plant will preferentially use the soil nitrogen rather than fix nitrogen. Rhizobium bacteria can live in the soil for a number of years; however, the most efficient nitrogen-fixing bacteria may not be among those that survive.

The Ministry of Agriculture publication Inoculation of Pulse Crops provides more detailed information on the use of nitrogen-fixing inoculants.

Fertility

Soil testing is recommended prior to planting for specific recommendations for nutrients.

Faba bean is a relatively high user of phosphorus. If narrow openers are used for planting, seed-placed phosphate fertilizer should not exceed 25 kg/ha (22 lb./ acre). Higher rates of fertilizer should be banded. Application of nitrogen fertilizer is not often recommended, since much of its nitrogen requirement can be derived from nitrogen fixation.

Sulphur is required for optimum yields, especially on Black and Grey wooded soils. Follow soil test recommendations.

For more information on the use of fertilizer consult the Saskatchewan Agriculture publications:

• Guidelines for Safe Rates of Fertilizer Applied with the Seed
• Sulphur Fertilization in Crop Production
• Potassium Fertilization in Crop Production

Additional information

Faba bean trials were started again beginning in 2006 to accommodate growing interest in this crop as a nitrogen-fixing high protein food and feed grain in moist areas. White flowering types are zero tannin. All coloured flowering types have seed coats that contain tannins and may be suitable for export food markets if seed size and quality match customer demand.

Maturity rating are based on days until swathing maturity but will vary depending on seeding date and weather conditions.

Seeding

Faba bean should be seeded five to seven cm (two to three inches) deep into a firm seedbed. Faba bean seed will absorb approximately their own weight in water before germinating so a dry seedbed will result in prolonged and uneven emergence. To avoid maturity problems, seeding should take place as early as possible in Saskatchewan when the average soil temperature at depth of seeding has reached 5°C.

Faba bean seed is highly susceptible to mechanical damage during harvest, handling or seeding operations. Dry seed (14 percent moisture or less) is brittle and can easily crack or split, leading to reduced germination.

The optimum faba bean plant population in dryland production is 44 plants/m² (four plants/ft²). The proper seeding rate can be determined using the following formula, which takes into account the seed size and germination level of the seed used.

Land Rolling

Faba bean has an upright growth habit and doesn't usually require land rolling.

For more information on land rolling pulse crops, read Tips for Rolling your Pulse and Soybean Crops.

Next: Faba Bean Crop Protection