To have any hope of making money from spring crops, getting them away well is vital, warns Strutt and Parker's Jock Willmott.
"Good swift establishment is the absolute key to profitable spring crops," he says. "It starts with sound early primary cultivation. That's usually, but not essentially, ploughing in dry conditions to preserve soil structure and minimise damage.
"Level ploughing or initial cultivation can make all the difference, because fewer passes with a secondary cultivator are then needed to create a seed-bed. This retains soil moisture, which is what usually speeds emergence."
Leaving aside spring cereals sown early (Dec/Jan), seed-bed conditions and soil temperature are more important than sowing date, he stresses. "Generally patience is rewarded with quicker emergence."
So how might previous cropping and cultivations affect sowing decisions?
"Previous cropping will generally only have any influence where the residues remain to be cultivated," he replies. "Late-harvested second wheat, for example, doesn't always offer a wide window for cultivation in the good conditions necessary ahead of pulses."
Spring cereals tend to be more forgiving of poor soil conditions than pulses and oilseeds, he notes.
"Spring combinable crops have short growing windows and must germinate and grow quickly if they are to yield well.
"Colder soils such as some chalks, particularly those on high ground and/or with the wrong aspect, for example north-facing, will not be particularly suited to oilseed rape or maize. Cereals in such fields would be a better choice.
"For similar reasons wet, heavy land is not usually suited to spring peas, but can produce acceptable linseed yields."
Non-inversion tillage is perfectly acceptable in place of ploughing where there is little straw to incorporate ahead of spring cereals, oilseeds and beans, says Mr Willmott. "Many growers of peas and maize still have reservations about that. But as long as all compaction can be removed and the crop residue won't interfere with the drill, then non-inversion as a primary cultivation can produce high margin crops."
Many growers have successfully broadcast spring cereal, bean and oilseed seeds and cultivated them in, he acknowledges. "It's not always the first route to choose, and it's generally only done when soils lie too wet to take a cultivator - but it is possible, though definitely not with peas."
Establishment nearly always involves a balance between appropriate working windows offering good soil conditions and calendar dates.
"Logically, the earlier a spring crop is drilled, the more time it has to develop roots and foliage to sustain it through summer droughts and build yield.
"In practice, it's the emergence date that's more important," he points out. "Drilling early into cold soil doesn't always get a crop off to the early start required. But if fields are prepared well and the soil is in good order there will be more opportunities to get the timing right and strike the best balance between soil temperature and calendar date.
"Sowing dates for most spring crops are quite flexible from mid-February to mid-April, depending on crop and where in the country you are." Given acceptable conditions, some South Downs/East Anglian growers do successfully drill barley in January and even December, he notes.
"As with winter cereals in recent seasons, sowing rates of spring cereals and beans have been edging up to compensate for potentially reduced tillering and to help suppress weeds. Pea seed rates have also edged as growers try to even out plant stands, but spring linseed and oilseed rape rates have remained relatively static."
Seed-bed nitrogen sense
Seed-bed nitrogen is always important, but especially so when, as in recent springs, that is only time when moisture is available, warns Mr Willmott.
"For this reason we're putting either all or more of the first split of nitrogen on into the seed-bed."
Maize must have adequate phosphate and potash, so seed-bed applications either before or soon after drilling may be important depending on indices, he adds.
"Again to split the risk it's comforting to have some nitrogen to apply post emergence to sustain canopy growth, but the efficacy of this application in dry springs remains under review."
All spring crops generally benefit from post-sowing rolling to conserve moisture and get the most from pre-emergence herbicides. "Rapid emergence leading to early crop canopy closure is essential to make the most of the crop and avoid successive weed flushes.
