Lincolnshire grower Tim Lamyman of Worlaby Farms near Louth has set a world record for oilseed rape yields this harvest.

Combining in the third week of July, the crop of conventional, open-pollinated variety Charger from breeder KWS averaged 6.14t/ha from an 8.9ha block.

Here, the grower gives an insight into exactly how he managed to coax 54.7t out of 8.9ha of his deep chalkstone wold brash soil.

Variety – We chose Charger because it’s joint-top variety for yield on the UK Recommended List and on the plots at Cereals 2013 it clearly had the potential to produce a good, secure canopy on stiff, short straw.

Here on the farm it was fast to emerge, with good vigour and rooting in what was a perfect autumn. It looked like a record-breaking crop from the word go.

Establishment – We used a conventional min-till approach and drilled the rape in mid-August. On our stony soils we don’t tend to suffer compaction below 10cm so we didn’t really need any deep loosening.

We first go went with a home-built tine/disc combination, which has a hefty power-harrow-type roller on it to consolidate the seed-bed. That works at 15-20cm and was followed by a Lemken TerraDisc, which tickled the top 5cm. Finally we used a Vaderstad Rapid to precisely place seed at 7-10mm.

We drilled the rape at 2.4kg/ha. That’s about half what it was five years ago – over time we’ve learnt that lower rates increase branching and the improved nutrition means the crop stands stronger for longer.

Nutrition – The most important thing is to supply the crop with what it needs, when it needs it.

The Charger had NHK Delta – a liquid nitrogen and potassium (15%N, 8%K) product – seven times throughout the season, starting at the two-leaf stage. That was in addition to two 200kg/ha applications of DoubleTop ammonium sulphate in the spring, the total coming to 220k N/ha – 216kg/ha from the bagged product and just 4kg/ha from the liquid.

Because it’s going on at such low rates, the Delta is easily integrated into most tank mixes, so we almost never have the cost of an additional pass from the sprayer. We just avoid mixing the boron products with the insecticide Maverick (tau-fluvalinate).

At flowering the liquid fertiliser regime was bolstered by a calcium formulation – Calflux – plus boron and molybdenum product Rainbow Wave to deliver all the essentials to the plant for the high-stress, high-demand pod-set period.

For the record-breaking crop the whole fertiliser programme came in at about £150/ha and added about 1t/ha to the yield. For the rest of the acreage the regime cost about £125/ha and added about £250/ha to the bottom line.

Disease – Because we’re tailoring the nutrition to the growth stage of the crop, it’s generally healthier than normal early in the season, but because it’s greener and the roots are bigger, the canopy tends to bulk up quicker in the spring. That inevitably leads to increased disease pressure, so we had to be pretty sharp with fungicide timings.

Weeds – Our biggest problem weeds in the rape were fat-hen, charlock, thistles and poppies, which we generally try to hit with a combination of Shadow (dimethenamid-P + metazachlor + quinmerac) and Centium (clomazone). We’re just beginning to see some blackgrass creeping in, which we try to keep on top of with Astrokerb (aminopyralid + propyzamide). That also gives us control of the meadow grass we tend to suffer with.

Growth regulators – The Delta liquid fertiliser has a type of PGR effect because it does such a good job of strengthening the roots and stems. Because of that we were able to get away with just one dose of tebuconazole.

Dessication – We aim to follow the Roundup (glyphosate) guidelines as closely as possible, waiting until the seed reaches 30% moisture before going in with the sprayer and leaving it 15 days before the combine gets going.

There’s little advantage in leaving spraying off any later, especially in a year such as this where disease levels are high and are starting to kill the crop off anyway.

Harvest – The tailored nutrition means the strong-standing plants can be tough to cut. The Calflux at flowering seems to strengthen the pods, which means we get hardly any shatter on the header. The reel just gently touches the top of the crop and there’s no seed shed until the pods hit the intake auger. Looking on the ground we have virtually zero header losses.

Staff – Without the dedication of our team and their tolerance of my exacting standards, there’s no chance we’d be growing record-breaking crops. Land work has to be perfectly even and level so that when it comes to drilling the rape it goes in at exactly 7-10mm depth.

And when it comes to spraying, I’m very particular. Because I do all my own spray programmes and tank-mix fertiliser, things can get quite complicated and with so many crops in the rotation – including potatoes – the spring/early summer workload is quite demanding.

See also: World record set by Lincs oilseed rape grower