Top winter bean grower shares his establishment tips
Lincolnshire grower Victor Barker consistently achieves high yields for his winter bean crops by ensuring he achieves high-quality seed-beds to enable good establishment.
Farming 160ha on the fens at Dowsby, Mr Barker’s winter beans usually yield about 4t/ha, but he always thought they had more potential.
This season he achieved his highest yield yet of almost 5t/ha after trying out a new variety.
Delay for blackgrass
Mr Barker’s cropping consists of spring wheat, oilseed rape, winter beans, cabbages, sunflowers and maize on his marine clay with silts soil.
Blackgrass is an issue on some of the heavier land, so he is keen to delay drilling of the winter beans to allow the grassweed to be targeted.
To achieve an effective stale seed-bed, he ploughs soon after harvest and then uses a Simba Cultipress with its row of tines and two sets of discs to work the top 50mm and level the ground, spraying off any blackgrass flushes.
In the past, Mr Barker would have left a much rougher seed-bed, but says that achieving a finer tilth is key to higher yields, although growers must avoid overworking the soil.
“You want a better seed-bed as it’s better for chemical control, and if the beans pod down the stems, they are easier to combine,” he says.
Growers who establish beans after the plough can suffer a yield penalty, as they will not be able to combine pods that set lower down on plants that are growing in hollows, he warns.
The beans are drilled with a power harrow drill combination as deep as possible to a depth of 5cm at a seed rate of 157kg/ha, and then rolled for good consolidation.
Drilling in the first half of November is the ideal time, says Mr Barker, allowing wheat to be drilled first and also for good blackgrass kill. It can be delayed even further, but the seed rate will need increasing.
Last season, the 12h of beans established well, except for a patch of silt that was targeted by mice.
Variety and pollination
Last season was the first year Mr Barker switched from his usual variety Wizard to grow Tundra, after the variety achieved the highest yield in variety trials managed by the Processors and Growers Research Organisation (PGRO) on his land.
Mr Barker does not aim for a particular target plant population, as the key to higher yields is pollination and a high rate of pod-set/sq m rather than plant density.
While his agronomist thought last season’s crop looked a bit thick, Mr Barker always believed it had potential to yield well, and was rewarded with his highest yield of 5t/ha this summer.
Whether this increase is solely due to the new variety, or whether the beans have benefitted from being grown directly next to six bee hives kept as a hobby on the farm, Mr Barker doesn’t know, but he does believe pollination is key to higher yields.
Accordingly, he has sown pollen and nectar mixes around the farm as part of a stewardship scheme to encourage pollinators.
“It’s one thing breeding new varieties, but understanding how we can get more pod-set would be great.
“I do think further significant gains could be made from understanding the effect of pollinators on the crop.”
Poor germination
One issue that growers will have to overcome this season is finding any seed. Despite yielding high, Mr Barker’s seed crop failed germination.
“I don’t know why the germination has gone, whether it’s the heat, or the light intensity, I just don’t know.”
After the summer heatwave, the beans were splitting open and shattering on the ground, forcing Mr Barker to combine them much earlier than normal.
“I could see the beans in the pods, and they had already suffered a bit of staining as the pods were open, so I had to combine them immediately,”
Despite rain overnight that stiffened the pods, and opening and slowing the drum as much as possible, the beans shattered during harvest.
Now, rather than seed, the crop will likely go for feed. Luckily, Mr Barker has a few certified beans left over from the past couple of years so will be able to grow the 6.5ha he has planned.
Expert top tips
The PGRO’s principal technical officer, Becky Howard, offers her top tips for the successful establishment of winter beans
Drill timings
In mild winters and where winter beans are planted early, vigorous growth can cause higher levels of brackling, lodging and chocolate spot.
Seed-borne leaf and pod spot and stem nematode can be very damaging in winter beans and it is strongly recommended that seed is tested for both.
Winter beans should not be sown too early (not before the second week of October) as crops that are too forward are more prone to disease and to the effects of severe winter weather.
Sowing from mid-October to early November is usually the optimum time, but acceptable crops have been produced from early December drilling.
Drill depth and cultivations
Beans should be drilled to a minimum depth of 3-5in into soil that is not compacted to allow good root penetration.
The method of planting can be either by drilling or ploughing in seed that has been broadcast on to stubble, but in the latter case, there will be some loss of uniformity and evenness in plant emergence and a higher seed-bed loss should be anticipated (20%).
Some leveling of the seed-bed may be required after ploughing in. The target plant population for winter beans is generally 18-20 plants/sq m established in the spring, with some varieties having specific information for seed rate (see below).
Typical target for plant population in winter beans |
|
|
Varieties |
Population (plants/sq m, established) |
|
General |
18-20 |
|
Clipper |
22 |
|
Wizard, Arthur |
23-26 |
|
Honey, Sultan |
28 |
|
Source: PGRO |
|
Seed rates
Field loss for drilled winter beans is 15% and PGRO has produced a seed rate calculator as part of the Optibean tool (Excel-based spreadsheet).
Alternatively, seed rate can be calculated using the following formula:
Rotation
To reduce the risk of a build-up of persistent soil-borne diseases such as foot rots caused by Fusarium and Didymella pinodella, field beans, broad beans, peas, green beans, vetches and lupins should be considered as forming a single crop group and grown no more than one in five years on any field.
Seed-bed quality
Beans don’t require a fine seed-bed and will tolerate cloddy conditions, although weed control may be poor. Over-cultivation should be avoided.
Beans are sensitive to soil compaction, which may lead to increased problems with foot rot infection and nutrient uptake.
Nutrition
Requirements of beans for fertiliser are small and no N is required. Where P and K are required, it is essential that it is placed deep enough into the seed-bed to allow full use by the crop.
Broadcast fertiliser should be ploughed shallow or applied over the furrows. It can then be worked in by subsequent cultivations, avoiding fine tilth and compaction. Fertiliser requirements of beans can be found in the AHDB Fertiliser Manual.
Blackgrass
Winter beans offer a good opportunity to tackle blackgrass populations using Crawler (carbetamide) or Kerb (propyzamide).
However, early drillings followed within seven days by pre-emergence sprays may not fully benefit from Kerb applications, which work better at lower temperatures (<8C) perhaps more associated with November and December.
Pre-emergence herbicides have a variable, but limited time of activity, which starts to decrease from the time of application.
Winter beans can be in the ground for a long time before the crop is at an appropriate growth stage for post-emergence bentazone, which is less effective in cool conditions.
For this reason, it may be worth considering keeping an eye on drilled crops and weather forecasts and delaying pre-emergence applications for as long as reasonably possible. This may extend the effectiveness of applications.
This approach offers a chance to move the period of weed control so it is more valuable, but does require increased attention to crop and weather conditions and is not without risk.
