With weather conditions favourable for rapid growth crops have grown quickly, with the majority of ware crops completing full ground cover by the longest day. This will enable crops to benefit from long daylight hours and, hopefully, lots of sunshine.

Extended spray intervals caused by wet conditions at the start of the rapid growth stage has allowed blight to become established in a number of areas and making sure that applications have contained products with curative as well as protectant activity has been crucial. Spray intervals, down to 5 days apart, over the last couple of weeks has enabled growers to get on top of the problem, but don’t be complacent. In my experience once blight is in a crop it will always be there and it is a case of managing it so that it doesn’t develop further.

A visit to the West Midlands potato day recently brought home to me the importance of cultivations and avoiding compaction. Where soils had been worked whilst too wet compaction was clearly evident and rooting was limited, as a consequence yield is likely to be reduced. Hopefully it is not too late to deal with the results of compaction. If you are aware of a problem then foliar feeds might help if rooting is limited, and also little and often irrigation,  although it will be important not to over-water as drainage will be compromised and as a result pink rot and soft rots are likely to become a problem.

Minimising the impact of both blight and rots are vital, particularly for those crops destined for store. Attention to detail now will pay off later. Monitoring crops for blackleg is also worthwhile; it always seems to be worse in some varieties than others. Bear in mind that if you are grading in to store blight and bacterial rots are easily spread to other tubers, particularly if skins are not quite set or damage occurs on the harvester.