Year two of the leek variety trial brought completely different weather and challenges, and brought forth some different high performing varieties. However, 'Chinook', 'Lancia' and 'Defender' proved to be top performers in both years, demonstrating disease resistance, vigor, and high uniformity. This year we replicated the varieties, allowing for statistical analysis, but the tremendously different growing seasons lead us to recommend looking at results from both years as worth considering. The notable challenges from this season were very regular rains during July and parts of August, and subsequent very high disease pressure. The previous season was much drier and disease pressure was negligible.

Results from the 2021 Leek Variety Trial

The invasive fly pest, allium leafminer (Phytomyza gymnostoma), has been established in the Northeast since 2016 and has caused crop damage as far north as Washington County, NY, as far east as central Connecticut, and as far west as the Finger Lakes region of NY. In research trials, the fall flight has caused damage to over 98% of leeks that were not covered or managed with insecticides.

Results of the 2020 leek variety trial with 36 varieties

Onion thrips populations have exceeded action thresholds in a few hot spots in Orange County. Review Dr. Brian Nault's insecticide recommendations for onion thrips management that incorporate newly registered products in New York State.

A new invasive insect pest in the Northeast known as the Allium leafminer (ALM), Phytomyza gymnostoma, damages crops in the Allium genus (e.g., onion, garlic, leek, scallions, shallots, and chives) and is considered a major economic threat to Allium growers. Originally from Europe, ALM was first detected in Lancaster County, Pennsylvania in December of 2015 and in New Jersey and New York in 2016. As of fall 2017, ALM activity has been confirmed throughout eastern Pennsylvania, New Jersey, Delaware, southeastern New York as well as Thompkins and Suffolk counties.

Last year we saw a lot of problems with root feeding damage from maggots early in the season, which has growers on edge about pest pressure this year. Seed corn maggots can damage a variety of crops, and in previous years have been observed on everything from sunflower shoots in the greenhouse to pea seedlings and onion transplants in the field. Onion maggots are more particular, and will only feed on allium hosts.