Aim to plant faba beans as soon as the field is passable, anytime from mid-April until early May. Avoid planting later than mid-May. The goal is to ensure they reach maturity before fall frost (105 to 110 days) and flower under cool temperatures. Soil temperature should be at least 3°C for successful germination. Seeds can germinate and emerge under cool soil conditions and seedlings are tolerant to frost.
The recommended seeding depth range for faba beans is 2 to 3 inches, ensuring adequate seed to soil moisture contact.
Target Plant Stand and Seeding Rate
The target population for faba beans is 45 live plants/m2 (182,000 plants/ac). For seeding rate calculations (lbs/ac), factor in thousand seed weight (TSW) and expected seedling survival for each seed lot. Seed moisture, handling and seedbed conditions affect seedling survival. According to the PAMI survey and Manitoba variety evaluation trials, seed size can vary widely from 335 to 789 g/1000 seeds.
Row Spacing and Equipment
As faba beans grow upright and do not branch out, narrower rows will provide faster canopy closure, better weed competition and moisture conservation.
Planters or air seeders can be used for faba bean planting, although air seeders pose a greater risk of plugging, damage to the seed and uneven seed depth. Due to the irregular shape and large seed size, plugging can occur at various points in an air seeder—the metering system, distribution system, blockage sensors and soil openers. Plant slowly (less than 5 mph) to avoid plugging issues.
According to a survey conducted by the Prairie Agricultural Machinery Institute (PAMI) across Saskatchewan in 2017, soil openers were the most common source of plugging. Openers with straight-through geometry and no obstructions or change in direction reduced the probability of plugging. Follow equipment manufacturer recommendations and consider a “practice run” to ensure there are no flow issues. Refer to the tips below and the PAMI report for full details on this project.
Tips to Avoid Faba Bean Plugging Issues
- Reduce planting speed to less than 5 mph.
- Use extra-coarse metering rollers or augers with a large volume between flutes or flights.
- Increase air flow through distribution system (i.e., set to maximum fan speed, install fan with high airflow capacity).
- Reduce number of tight turns in the field to prevent innermost openers from reversing in soil.
- Eliminate sags in distribution hoses and avoid over-tightening hose clamps.
- Deliver seed via fertilizer tubes, if larger cross-sectional area than seed delivery tubes (Figure 5)
- Remove inline blockage sensors that may obstruct flow.
- Meter seed out of two tanks instead of one for desired seeding rate and reduced flow-rate from individual meter.
- Sieve out largest seeds prior to seeding. Faba bean can vary widely in seed size.
- Reduce seeding rate if germination and expected seed survival are high.
- Seed the field twice over at half the application rate.
- Reduce outside diameter of metering rollers, which increases clearance with metering housing and reduces the probability of seeds jamming between the roller and housing.
- Use vertical tower-style distribution manifolds. Some are more prone to plugging than others.