b'What To DoWhen Frost HitsTips for making the best of a difficult situation.BY: TREENA HEINWHEN A PRE-HARVEST hard frost hitsa temperature of -2.22 C or belowgrowers are faced with some thorny challenges. While a light frost may only damage the tubers in the top part of the hill, a severe frost can take out much more. There has been early frost three out of the last 10 years in the Maritimes, and out of those incidents, last year was the worst for frost-damaged potatoes in the region, says Khalil Al-Mughrabi, a pathologist at the Potato Development Centre of New Brunswicks Department of Agriculture, Aquaculture and Fisheries, and an adjunct professor at Dalhousie University. To prevent this situation, growers should consider harvesting tubers before severe frost is likely, preferably when the tuber pulp temperature is above 7 C, he says. Growers should also ensure hilling is properly formed to help protect tubers from freezing temperatures. Additionally, growers should keep an eye on weather conditions and forecasts in their regions. Here in New Brunswick, we have a harvest advisory program that runs between the middle of September until the middle of October, Al-Mughrabi says. In addition to providing growers with weather forecasts that help them decide when to harvest, this program gives growers soil temperature and moisture at a depth of six inches, tuber pulp temperature and current air temperature.If a hard frost does hit before your harvest, do not disturb tubers until they have warmed completely. Waiting a few days to harvest is a good practice to follow in identifying any damaged tubers, says Al-Mughrabi. At that point, crews can cullStoringpotatoes that have blackened or started to rot. Growers may need extra people onfrost-damaged the harvester or bin loader to remove as many visibly-frosted or rotted tubers aspotatoes might cause potential problems possible, and that harvest should be stopped if there is wet weather, he adds.throughout the Tubers should be handled carefully to minimize bruising, as infections canstorage season, which occur through wounds. Also remove as much soil and debris as possible, as thiscan be costly.will only restrict airflow in storage, which leads to hot spots and tuber breakdown, says Al-Mughrabi.36 SPUDSMART.COM FALL 2019'