Tillage: Sowing conditions rather than date is the critical factor for beans
Published 16/03/2016 | 02:30
Last year many had taken advantage of a good spell in February to get beans sown into excellent conditions. This year of course it's a bit different. Beans performed well last year and there will be plenty of interest in the crop again this year.
Work carried out in Teagasc Oakpark, albeit results from one season at one site, will give a level of comfort to those of us accustomed to pushing sowing the crop in January or February.
These results suggest that sowing date is not as critical a factor as we thought. Sowing conditions are however critical. The seed will not take kindly to being flung into a compacted mess, and will respond with poor establishment and consequently, poor yield. Another achilles heel of the crop, weed control, will also suffer from poor seedbeds.
The only viable weed control strategy for beans is the use of pre-emergent residual herbicides. Beans do not form a dense crop canopy to smother out late season weeds, so the herbicide is required to work for the full life cycle of the crop, or up to 26 weeks.
In order to be effective therefore, everything has to go right for the herbicide to work season long.
Applying residual herbicides onto a cloddy seedbed is not the way to get the best out of the herbicide and the worst case scenario is a new flush of weeds starting to swamp the flowering crop late in the season. 'Well sown is half grown', is a mantra repeated ad-nauseum, but with good reason.
Given the long winter we have endured, there are plenty of organic manures like slurry, farmyard manure and even soiled water looking for a new home and given the outlook for crops this year, getting the P and K requirement from organic manures makes sense.
However, with the high proportion of land that is sown into winter cereals this year, in some areas there is a shortage of land available to take manures this spring and land destined for beans may well be a good opportunity to utilise organic manures.