Late Planting Can Result in Better Yields, AHDB Says
AHDB specialists have offered advice regarding the potato planting in the UK, saying that a late planting might be better for the yields.
“After watching it rain for six weeks, as your expected planting dates disappear behind you, it can be tempting to jump on the planter at the first break in the weather. Patience and risk mitigation now, can help prevent poor results come harvest,” says AHDB’s Claire Hodge.
The key message is not to panic, waiting a few days and planting in the right conditions is often better than ‘losing’ a couple of days growing time.
This article describes some of the key risks associated with the timing of planting, and highlights some resources available to help manage them. We would always recommend talking with your agronomist or advisor before acting, or you can find your local AHDB Knowledge Exchange Manager here.
Planting in wet conditions can lead to yield losses larger than that you would experience from delayed planting.
Mark Stalham of NIAB CUF, a pioneering plant science organization in Cambridge, said: “Serious yield loss due to late planting only really starts occurring after May 7 in England for a Group 3 determinacy variety. With longer daylight hours in Scotland, this may even be a few days later. The risks are associated with delayed emergence and the crop not reaching full cover by the longest day of the year.”
On the other hand, poor soil conditions can lead to compaction, Stalham said that it is “highly likely that a 2 – 5t/ha yield loss may occur if poor soil conditions lead to compaction.”
Mark Stalham of NIAB CUF said: “The shorter season and potential compaction issues means that tuber size is likely to be smaller owing to lower yield. Seed spacing needs to be widened to achieve the optimum size specification”.
AHDB has seed rate guides for eight popular varieties here. The guide works on a planting date of the 15 April, so this will give you a starting point from which to begin. There have also been demonstrations conducted on seed spacing at SPot Scotland results can be viewed here.
A shorter season will reduce the nitrogen requirement for the crop. The Nutrient Management Guide (RB209), Section 5 (Potatoes), contains tables (page 22) with suggested nitrogen rates based on growing season length.
Mark Stalham said: “A shorter season will typically reduce the N requirement (by 20, 13 and 10kg/week for Group 1, 2 and 3 determinacy varieties, respectively).”