Classes of dry bean
The most common classes of dry bean grown in Western Canada are:
- great northern,
- small red,
- pink, and
Smaller amounts of cranberry and various kidney types are also grown.
After germination, the cotyledons (seed leaves) push up through the soil and are exposed above the surface. The first true leaves are single opposite leaves. All later leaves have three leaflets, called a trifoliate arranged on alternate sides of the stem.
Flowers emerge from the upper leaf axils, and can be white, pink or purple in colour depending on the market class. The flowers are self pollinated before they open. Under heat or moisture stress, flowers can abort. Yields increase significantly, however, if excellent growing conditions occur at the time of flowering and pod formation.
Wide-row production involves the planting of bean as a row crop with seed rows 55-90 cm (22-36 in.) apart. Specialized row crop equipment is needed for planting, inter-row cultivation, and harvest. This production system is very successful and often produces yields higher than narrow-row production.
Narrow-row production of bean refers to solid seeding in row widths from 15-30 cm (6-12 in.). Some growers in Saskatchewan are interested in dry bean production where they can use their existing crop production equipment. Growers only need to make slight modifications to pea or lentil growing seeders, sprayers and harvest equipment. Narrow-row production can also affect the variety chosen, seeding rate, weed and disease control, and harvest practices.
Bean seeds contain 22-24 per cent protein and are high in dietary fibre and complex carbohydrates. Bean is gluten-free and low in sodium, making it suitable for gluten-free low salt diets. Nutritional information for dry bean as a source of food is available from Saskatchewan Pulse Growers.
Regional adaptation and field selection are two very important factors to consider when growing dry bean in narrow rows. Bean is not widely adapted to every region and soil type. The crop is best suited to medium-textured loams in regions that are not prone to late-spring or early-fall frosts. Because the crop has no frost tolerance, areas that are prone to frost should be avoided.
Early experience suggests that narrow-row production of dryland dry bean is best suited to the thin black soil zone where late summer rainfall amounts tend to be higher, and late-spring or early-fall frosts are typically not a high concern. Growers in other areas of the province are experimenting with dry bean production to determine if the crop is more widely adaptable than currently thought.
Dry bean crops leave little residue on the soil, so growers should consider protecting their fields from erosion by planting dry bean on cereal crop stubble and by following dry bean with a cereal crop. Previous crop residue must be chopped and evenly spread before planting.
Heavy crop residue slows soil warming in the spring, slowing germination and emergence of the crop, and increasing the risk of seed rot and seedling blight. For this reason, some growers prefer to plant dry bean on fallow fields.
Field records should be maintained to be aware of potential crop injury due to herbicide residue. Dry bean seedlings are susceptible to the soil residues of numerous herbicides.
Factors to consider when selecting a field for dry bean:
- Drainage - Dry bean will not tolerate saline soils, wet soils or soils prone to any standing water. Saturated soil conditions for 24 hours will severely damage seedlings, usually leading to delayed maturity, and smaller and shrivelled seed.
- Field history - Careful consideration should be given to the crop rotation history to ensure volunteer crops can be managed in the years of dry bean production. Bean is highly susceptible to Sclerotinia stem rot (white mould) and tight crop rotations including other broadleaf crops such as canola, mustard, pea, lentil, sunflower, and potato should be avoided
- Rocks and stones - A land roller should be used to level soil ridges and press any stones into the soil. Do not roll dry bean after emergence. Excessively stony fields should be avoided to prevent harvest equipment damage.
- Soil temperature - Dry bean is better suited to soils that warm rapidly in the spring. Soils that are slow to warm or are covered by thick residue from the previous year's crop can lead to very slow bean emergence and development.
Since there are numerous herbicides that may have residues that could damage bean, it is important to know that these residues become of greater concern following dry years.
Dry bean should not be grown in the same field more often than once in four years to reduce the risk of soil-borne and residue-borne diseases. Sclerotinia stem rot (white mould) is a major concern in bean production, and planting bean in a field with a history of sclerotinia in other broadleaf crops within the past four years should be avoided.
Much of the dry bean production in Saskatchewan occurs in the irrigation area near Lake Diefenbaker. Bean yields are highest when no drought stress occurs during the flowering and pod-filling period. Irrigation is used to reduce losses due to drought. Irrigation increases the risk of white mould and delays the maturity of the crop.
For more information about the irrigation of the dry bean, see the The Canada-Saskatchewan Irrigation Diversification Centre (CSIDC).
There are many bean classes and varieties grown successfully in wide-row production in Western Canada.
There are three growth habits of dry bean (refer to Table 1):
||determinate bush type;
||indeterminate bush type; and
||indeterminate vine type.
The determinate growth habit has five to nine nodes on the main stem with two to several branches. The main stem and branches end with a cluster of flowers. The indeterminate growth habit may have 12 to 15 nodes on the main stem. Vine types usually develop vines just before the start of flowering and flowers are produced along the vines.
Generally, the best bean varieties for dryland narrow-row production systems have early maturity and carry their pods higher off the ground to allow for the successful use of a swather or a straight-cut header. The pod clearance rating in Table 1 describes the percentage of pods that are at least 4.5 cm (two in.) above the soil surface. In short season regions, only varieties with a maturity rating of "early" should be grown.