DAERA Notes: Crops

Apply nitrogen early to encourage tillering
Apply nitrogen early to encourage tillering

WINTER CEREALS

In contrast to a year ago, when winter crops were sown in good conditions and enjoyed a relatively dry winter, this year’s crops are thinner, more backward and showing signs of stress. This is due to the lower temperatures and continually waterlogged soils. High winter rainfall means a bigger proportion of soil N has been leached out of the rooting zone, so the priority for these crops will be early N to kick start them back into life.

Normally winter barley receives at least one third of its total N during late tillering, before mid-March. Winter wheat should receive a third of its total N before the end of March. For late drilled, thin or struggling crops either sow N earlier to encourage tillering or if ground won’t travel, increase application rates at first dressing once field conditions improve. Sulphur also leaches easily, therefore include at least 20-30kg per hectare in your early fertiliser dressings and top up remaining P and K.

Regarding weed control, relatively little herbicide was applied in the autumn. Prioritise winter barley, as the few remaining grass weed herbicides effective for this crop only work on small grasses. Also cut-off dates for latest application are earlier than for winter wheat. Consult product labels carefully for cut-off dates and latest growth stages.

SPRING CROPPING

Continual poor weather since last summer has resulted in a smaller area of winter crops sown than initially planned. Certain fields now destined for spring crop have been badly compacted, rutted or waterlogged and may struggle to contribute a positive financial return this year.

Fallow or short term grass leys may be worth considering in the worst affected fields. This would allow an opportunity to rectify compaction and drainage issues and carry out remedial work to get crop rotations back on track, minimising the long term impact of last year’s weather.

It is worth noting that both fallow and temporary grass count as individual crop types for the crop diversification requirement within greening. This could be a useful option for growers with a two or three crop requirement who were unable to get their planned winter crops sown. You are advised to use the 2018 single online application to check your crop diversification requirements to help make the necessary cropping decisions.

With demand for spring cereal seed likely to be strong this year, some growers are considering using home saved seed. If you are using this option, a seed germination test is money well spent. It confirms the purity and viability of the seed and is the starting point for seed rate calculations. Seed testing is carried out at the Official Seed Testing Station at AFBI, Crossnacreevy.

POTATOES

With some of last year’s potatoes possibly still left to dig, don’t neglect preparations for this year’s crop. Inspect fields intended for potatoes to identify drainage or compaction issues that need to be addressed before ploughing. Soil should be sampled as soon as possible and where there is a high potash requirement it is advisable to apply immediately after ploughing, particularly where muriate of potash is the main source.

Seed preparation for planting

Attention to detail during handling and preparation of seed before planting can result in increased early tuber yield, whilst optimising fry colour and skin quality. Carefully check the seed as it arrives on farm and have samples hot boxed to determine the presence of disease and overall sprouting vigour.

Sprouting and chitting

Pre-sprouting systems (bag or tray) must ensure adequate temperature, ventilation and light to control sprout growth and protect against frost. Set seed from early varieties in sprouting boxes with the aim of promoting apical dominance, that is producing one strong sprout per seed tuber. One stem will give small numbers of large tubers early. The opposite holds for maincrop potatoes where multiple sprouting is encouraged to produce many tubers which can increase in size over a longer growing season.