Fulcrum CRV provides the crop with essential sugars and other micro-nutrients just when it needs them, allowing the crop to grow more rapidly. However, if applied too soon or too late it may not work so effectively. Growers are warned the best way to find out what is going on under the soil is to test dig a small part of the field and check for stolon hooking on tubers.

Dr Phil Holden, sales director for SvG Intermol Ltd, said: 'The reason that timing is important is to do with the way that Fulcrum CRV works, which is completely different to other products sold as potato growth promoters.'