With harvest well underway, the establishment of cover and catch crops will be at the front of many farmers’ minds. However, Hutchinsons’ technical manager Dick Neale is warning that moisture may be in short supply.
“As we are aware, weather can change rapidly with hot dry periods often coming to an abrupt end, however despite a small amount of rain being forecast into the beginning of August, it is not predicted to significantly change the dry status of soils sufficiently to sustain good growth.
“Establishment of catch crops, cover crops or oilseed rape is therefore likely to be extremely difficult currently, and the use of catch crops after forage rye, vining peas and winter barley are also unlikely to be successful for now.”
He added that the lack of soil moisture should override all other factors regarding species mix or drill dates. “Where soil moisture levels are higher, say further north or in the west, it is key to plan cover or catch crops with the desired outcomes in mind.
“Cover cropping is not new but in the rush to sell options or ‘keep it cheap’ at the farm level, it is important not to overlook some fundamental realities. Think about the following crop, intended drilling date, available equipment (topper) or livestock (grazing) and drill type.”
Mr Neale explained that growers need to carefully choose the mix or ratio of species based on soil management needs, aggregation, moisture management, surface structuring, weed suppression and nutrient fixing.
“For example, multiple species are useful to ensure the reliable establishment, ensure rooting is engaged throughout the soil profile, bring diversity into the rotation and ultimately balance the potential negatives of any individual species.
“In conditions such as those currently being experienced, with ground cleared by end of July but soils remaining dry, provided there is a least sufficient moisture to achieve germination, then consider C4 plants such as millet and sunflower as these will tolerate dry soils far better than brassicas or legumes,” said Mr Neale.
“Linseed and buckwheat can also be added as they are more robust in drier conditions.” He warned that cover crop failures are often the result of expectations being too high, particularly when combining is completed before cover sowing is even contemplated – valuable growing time is lost.
“Often cover crop seed is broadcast onto dry stubble – this is not going to work. Termination timing is vitally important as covers move and manage moisture within the soil, which is generally a good thing during the autumn growth period, but can rapidly switch to upper soil wetting in later winter and early spring, so this needs to be avoided.”
Establishing cover crops (is like any other crop)
- Drill into a moist, growing seedbed with good seed-to-soil contact at the correct depth;
- Drill at the correct time;
- The cover crop seedbed develops into the next cash crop seedbed, so it’s important to get it right;
- In a single year, the financial outcome of a cover crop is likely to be neutral at best, with a positive financial outcome being cumulative across the rotation;
- Consider mixed species that are suitable to the conditions.