Potato growers across Prince Edward Island (PEI) are seeing rapid crop development as mid-May plantings reach flowering and tuber initiation, aided by a shift to drier, sunnier weather following spotty showers in recent days.

According to data from the PEI Department of Agriculture weather stations, most of the Island received 10–15 mm of rainfall over the past week, with slightly higher accumulations (20–30 mm) recorded in Eastern Kings. While this has eased soil moisture concerns in some areas, growers in East Prince have already begun irrigating as fields approach the critical tuber initiation stage. “Low soil moisture at tuber initiation can negatively impact tuber number per plant and increase the incidence of common scab,” agronomists warned.

Spore and pest monitoring data

The first air spore collections of the season show no detection of late blight spores across PEI or in neighbouring New Brunswick. However, late blight spores continue to be found in Maine, though no field infections have been reported. Early blight spores were identified at one site in East Prince at a notably high number, while brown spot spore counts remain low in most locations except for two sites in East Prince where higher levels were observed.

Agronomists are advising timely fungicide applications to susceptible varieties, particularly before row closure, to ensure effective coverage of lower leaves. Early planted varieties such as Targhee, Ranger Russets, and Dakota Russets should be prioritized for treatment.

Aphid surveillance also intensified this week, with 4.31 aphids per sample recorded across 29 traps. One green peach aphid was detected in East Prince – an unusually early appearance for the region – though agronomists note that green peach aphids were observed in Maine more than three weeks ago. The majority of aphids identified are non-colonizing species, but seed growers are advised to maintain tight spray schedules, including frequent oil applications, to prevent PVY spread.

Additional pest concerns

Scouts are reporting detections of European corn borer (ECB) egg masses, some at the blackhead stage, in West Prince and other areas. Colorado potato beetles remain widespread, with variable levels of damage across fields, though many growers continue to achieve effective control through in-furrow neonicotinoid applications.

Volunteer potatoes are prevalent this year, particularly near woods and hedgerows. Agronomists are encouraging growers to monitor previous-year fields closely for volunteer plants that may escape beetle feeding.

Upcoming events

The next crop update meeting is scheduled for Tuesday, July 15, at 2:30 p.m. at the Ag Insurance Corp Building in Kensington, with an option to join remotely via Zoom. Additionally, the University of Prince Edward Island (UPEI) will host a Sustainable Agriculture Conference on August 5–6 in Charlottetown. Registration is open at a cost of $125.