Potato Review

CROP STRATEGIES www.potatoreview.com POTATO REVIEW JANUARY/FEBRUARY 2023 19 He adds that research has suggested that depths can reduce fuel usage by up to one third. Moving on to discuss the costs of irrigation, Andrew highlights that a proper assessment should balance the costs and bene ts of irrigation, looking at quality and yield against energy used and water costs. “Irrigation needs to be done when crop response is at its greatest – which is tuber initiation and tuber bulking. “If soils are too dry, the seed potato will not throw as many daughters as it may be in survival mode, hence ensuring adequate water is available at this time is key to setting up a good crop. “ ere is of course the theory that roots will grow down in response to dry soils to seek out and scavenge water and nutrients, but rst of all they need the moisture to establish.” Andrew goes on to note that trickle irrgation costs per ha are about the same as overhead gun irrigation costs, but set-up costs are slightly higher because the equipment has to be rolled out for use and then collected up again after harvest. However, on the plus side, trickle irrigation is more water e cient as uses about 30percent of the volume of overhead irrigation. Where gun irrigation is used, increased fuel costs have increased the average cost to £130 per ha for fuel alone to work the pump, he adds, estimating that the typical total irrigation cost per ha for 125mm/season could be £600. Irrigation is also key at tuber initiation for scab control. e other key time is tuber bulking, which in maincrop varieties is from the third week of June until the second week of August. “Many of the crops grown in 2022 really struggled at this time because temperatures were really hot, and so the crop transpiration rate was very high. As a result, many of the crops were really not we’re really not receiving enough water they were just being teased with irrigation.” He adds that where gun irrigators were used, much of the irrigation water evaporated before reaching the crop. “It is a good idea to reconsider the bene ts and costs of moving to trickle irrigation. It is kinder to the crop and there is no wastage or run o but managing it is an ongoing process and a continual operation. “However, it is important to mention that the Environment Agency is looking to revoke licences where possible, so if you inform them you are going to move to trickle irrigation, they may cut down your licence water consumption allowance. “ Think local Andrew recommends keeping current fuel costs in mind when making decisions on which elds to rent. “If you rent ground 30 miles away, there will be implications of transporting inputs over longer distances, and also at lifting. “But also think through how long you’re going to spend on the road as you will have to travel to apply plant protection products search as blight sprays. Local tra c conditions can also mean trips take longer, particularly if there are tra c lights or the road goes close to a school.” Seed potatoes Seed potatoes are key to growing a successful crop, and maintaining maximum vigour after delivery should be top of the agenda for growers. However, in many cases, it is almost an afterthought, he says, re ecting, they are still often treated as a commodity rather than a specialist input that needs attention to detail when it arrives on-farm. . “I have seen a number of examples where temperatures may have been very cold during transport but then the seeds are placed into warmer storage, which may cause condensation and also raise the potential incidence of early sprouting. “When seed arrives, it should be carefully inspected to ensure that they meet the order speci cations and quality requirements. Each bag should be sealed with the details of variety, grade and size on the label.” e bags should be unloaded into clean boxes which have not been treated with sprout suppressant (especially old boxes which may have traces of CIPC), cured and placed into storage. He adds that AHDB advice says that store temperature will normally need to be 3 deg.C, depending on the time the seed potatoes will be stored, and if this is less than ve weeks, 4 deg.C may be enough. Storage – growers under pressure from energy and sprout suppressant costs Getting any leaky stores xed should be high on the agenda, Andrew says. Storing potatoes need 1 1/2 to 2 kilowatts per ton per week, and energy tari s could make or break pro tability. e recent energy price hikes have meant that those who have had to renew their tari s paying much higher rates, leading to huge di erences in storage costs. “Metering every store is a good idea because it really helps you gauge what is happening.” But it is not just energy costs that makes storage expensive, and since the withdrawal of CIPC, the currently available sprout suppressants (orange oil, spearmint oil, ethylene and DMN) are more expensive. As a result, many growers are becoming more judicious in their use and only applying them when they really need to. “ is year, pro tability will depend on optimising e ciency and cost- e ectiveness by making a number of small changes which add up.” Top tips for planning 1. Make a realistic budget for inputs and outputs to guide decisions. 2. Choose elds carefully, and the implications of their location. 3. Where possible, do thorough soil tests to better understand nutrient availability. 4. Consider costs of capital expenditure and costs of hiring machinery. 5. Invest in store integrity to minimise energy costs. Assess new varieties to find whether they fit with your system - and whether there is a market for them.