THE MAJOR potato growing areas of England are wet, wet, wet at the moment, with most having received 150mm (six inches) of rain during June and a Scottish growers' delegation to the two AHDB Strategic Potato (SPot) monitor farms in the south last week discovered that irrigators had lain unused for four weeks.

Even on the dry, sand lands at the 24,000-acre Elveden Estate, in Suffolk, there is no moisture deficit, with both the 400,000 m3 reservoirs full to overflowing.

Estate manager, Andrew Francis, has 38 hose reels and 25 linear irrigation rigs at his disposal and they would normally be flat out at this time of year applying water to 1175 acres of potatoes, as well as to large areas of onions and field vegetables.

He said he would normally aim to apply 15mm of water every three and a half days and uses neutron probes to transmit soil deficit information back to his office. Such is the precision involved, that he reckoned operating within a 12-hour window can be critical in keeping common scab at bay.

Elveden is in its first year as SPot Farm East and field-scale, non-replicated trials are being used to assess techniques on scab and potato cyst nematode (PCN) control as well as looking at nutrition and herbicide choices.

This is the same approach as is being taken at SPot Farm West in Staffordshire and is likely to be adopted for the Scottish SPot project at Bruce Farms, Meigle.

There, potato manager, Kerr Howatson, is responsible for the 700 acres of potatoes grown by the Bruce family and, after viewing the sites in England, last week, he said was looking forward to helping choose trial topics relevant to Scottish growers.

The SPot at Meigle will be previewed on July 12, with an open farm tour which will include an opportunity to see cultivation trials at nearby Hallyards Farm. The SPot Farm project, which is facilitated by AHDB Potatoes, will run for three years and starts officially in January, 2017.

The wet weather across England has made both Mr Francis and SPot Farm West host, James Daw, think hard about soil slumping after planting. The land at Thorpe Constantine, in Staffordshire, where Mr Daw grows 800 acres of potatoes, is heavier than that at Elveden. He has long made the point that potato growers cultivate soils to too great a depth and create too fine a tilth.

“In general, tines are good and bed tillers are bad. They should only be used where absolutely necessary. I also see a need to allow oxygen into the ridges at this time of year or a little earlier,” he told the Scottish delegation.

Mr Francis has a similar view and would also at the same time like to be able to inject fertiliser into the drill in June and, possibly, a liquid nematicide.

Machinery firm, Standen Engineering, based at Ely, in Cambridgeshire, has been working on a machine capable of performing just such a task in a growing crop using 6mm wide knives to break up the side of the drill. These shield injection pipes capable of directing liquid into the root zone.

Autumn-sown cover crops have been used on part of the SPot West site, with Mr Daw reporting much easier cultivations where the roots from the oat and vetch mix had been effective at breaking up the soil and drying it out in a wet spring.

PANEL

Issues with Scottish seed

“Scottish seed potatoes are OK, but we could do to have more details about how they have been grown and stored. The growers have all the information but it doesn’t get passed on,” said Elveden Estates manager, Andrew Francis.

As an example, he pointed to the processing variety, Shepody. Knowledge of previous handling and storage, including harvest date, would allow him to physiologically age the seed in such a way that he could manipulate tuber numbers.

Elveden Estates, the site of SPot Farm East for the next three years grows 1175 acres of potatoes including 325 acres of salad varieties, 275 acres of standard whites and 575 acres destined for processing with McCains. Russet Burbank is its major variety for processing.

At SPot Farm West, James Daw sources seed from England and Scotland. He sprouts seed in trays and believes that, despite the expense involved, it provides an improved margin.

One of the trial sites on the farm compared sprouted and non-sprouted crops of chipping varieties, Markies and Pentland Dell.

Bruce Farms, at Meigle, soon to be host of the Scottish SPot is already committed to sprouting seed in trays, with 275 tonnes handled that way most years. Potato manager, Kerr Howatson, acknowledges the high labour cost but believed handling in trays paid dividends,especially when used in conjunction with a belt-type planter.