Potatoes
Potatoes are our mainstay at Pengelly Farms; every year, we plant, harvest, store and sell around 16,500 tonnes worth from about 1,200 acres – that’s heavier than 2,500 elephants and the area of 750 football pitches!
A lot of work goes into getting a potato from a field to your plate – here’s the journey of a Pengelly Farm potato, throughout the year…
November to May – Planting
The journey begins in autumn each year, as we source land to grow our potatoes. Fields are tested for nutrient levels and pH, and have a risk assessment carried out to ensure we can work in them safely. Potatoes are usually only grown in the same field once every 5-6 years, often being rotated with our Maize, Sugar Beet and Rye crops.
In early January each year, our planting teams descend on the fields of West Cornwall to plant our early potatoes – the very first are on the clifftops overlooking Porthleven and Penzance.
The fields are ploughed, cultivated, and then tilled into ridges across the length of the field.
To prevent damage to the crop during its growing period and also when harvesting, we de-stone the soil before planting. The stones are incorporated back into the field post-harvest to maintain a good soil structure, and return the field to its original state.
Our seed potatoes are planted in the ‘destoned’ beds about 10cm apart and are then covered with soil. Our very early crops are covered with polythene covers to protect the growing plants from the winter frosts that we sometimes see until late March/early April. The covers are removed in mid-April and are then cleaned and recycled through a local company.
During the growing season, the crop is protected from pests, weeds, and diseases (only when the required thresholds are met) by the application of specialised and targeted plant protection products which help to maintain crop vigour, yield potential and quality.
May to October – Harvesting & Grading
We harvest our potatoes between May and October, and only when they are ready. Throughout the growing season, we monitor changes in the colour of the plants’ leaves, as well as carrying out weekly yield digs and quality assessments to ensure they meet the required specification.
We harvest and grade between 250-350 tonnes of potatoes per day, which get carried back to the farm by tractor and trailer from across Cornwall.
Once back on the farm, the potatoes are processed through our Haith grading system which uses optical sorting technology to remove soil, stones and foreign objects from the harvested crop. The potatoes are split into (up to) 7 sizes depending on the intended customer, the product line they are destined for, and whether they are for immediate use or short-term storage.
October to June – Storage
We store up to 10,000 tonnes of potatoes in temperature-controlled buildings, which help to keep them in the best condition to ensure they’re available all year round. We carry out daily and weekly checks to monitor airflow, air quality, crop temperature and moisture. If we don’t get it right, we risk writing the entire crop off.
Despite appearing durable, the potatoes still need to be handled with great care to avoid damaging the skins or causing bruises. Any damage will prevent the potatoes storing well and will reduce their overall quality. So, first we carefully split the potatoes by size in the field and store them in specially made wooden potato boxes that stack on top of each other. This system is more flexible, making it easy to store different varieties in the same area, and remove any crop if required.
When we store potatoes, we’re effectively putting them into hibernation to halt the growing process. To do this, we make sure it is pitch black in the store and then we don’t move the potatoes again until we are ready to use them. Potatoes naturally want to keep growing, and we daren’t wake them up! We have to be very careful; any movement or knocks could spark them back into life. Throughout the Winter, we spend a lot of time going in and out of the stores, sampling potatoes and monitoring temperature levels.
From this point, potatoes in storage are either sold to customers as needed, or set aside as seed potatoes, treated, and re-planted into the fields to grow more potatoes, continuing the cycle!