Top-Performing Annuals from the University of Minnesota’s Summer Trials

For nearly 100 years, horticulture research has been conducted at the University of Minnesota West Central Research and Outreach Center (WCROC) in Morris, MN. With more than 4 acres of impressive public display gardens, including 400 annual cultivars, WCROC offers an educational landscape for home owners, master gardeners, growers, and flower enthusiasts alike to see just how annual flowers perform under Minnesota’s unique growing conditions.

Spring weather conditions were finally favorable for planting trial plants in late May 2019, even though the month of May was the second coldest on record, according to Steve Poppe, Horticulture Scientist at the University of Minnesota. June and July had about average temperatures, while August had below-normal temperatures. May through August had above-average precipitation. Weather data has been taken daily at the WCROC since 1885.


In 2019, WCROC trialed 410 annual flower bedding plants, representing nearly 20 plant breeding companies from around the world. Flowers were planted into garden beds, handing baskets, and containers. Annuals flowers were evaluated multiple times throughout the growing season based on characteristics, performance, color, and vigor. Only the top-rated flowers are considered for the distinction of being a Top Ten Performing Annual, and the 2019 Top Ten varieties are featured in the slideshow above.

In addition to the Top Ten, there were other annuals that received excellent ratings in 2019.  Most of the seeded Impatiens, including the Beacon, Super Elfin, and Imara series, had above average or excellent ratings throughout the growing season. They were all equal in performance, vigor, and flowering ability, and had no apparent symptoms of downy mildew. Also, many of the seeded Vinca flowered continuously, looked healthy, and were a real eye-catching annual flower in 2019.  Trial managers were surprised by their performance since the growing season was wet and Vinca tend to like it a little drier.

For a complete list of all WCROC trial results, go to Check out more results from 2019 field trials here.