Montage of red petunias: in a container, in a bed and individual red petunia flowerThe UT Gardens serves as one of 34 nationally recognized All-America Selections test sites. Leading commercial plant and seed companies support the gardens through donations and in turn receive information on heat and cold tolerance, flower production, plant uniformity, flower and plant size, pest resistance, and landscape appeal. Such information is important to these companies to help them determine what plants ultimately reach the commercial market.

The UT Gardens have two evaluation sites, one in Knoxville representing the Eastern climatic conditions of the state and one in Jackson, representing the Western climatic conditions of the state. Knoxville and Jackson are approximately 300 miles apart. Having trial locations in both the Eastern and Western portions of the state provides the industry with evaluations from the different climatic regions found in Tennessee.

Getting the word out not only on what thrives in these southern test gardens, but also what fails is important. Each fall and winter, numerous industry and gardening magazines as well as newsletters inform gardeners, landscapers, and professional growers of the evaluation highlights. Plant evaluation data is published each year in a UT Agricultural Experiment Station Research Report. This report is sent to industry supporters or anyone desiring a copy. Links to reports from current and previous years can be found below.


Herbaceous Plant Trials

We've just posted the 2019 Trials data based on observations taken at our Jackson site. You can also check out the following trials data:A grouping of different species of conifers

This feature is in addition to the annual Knoxville and Jackson Garden Best Plants report which will be available below soon. Anyone who wishes to receive a copy can download it from this site. You can also access the reports from previous years below.

Each trial variety was evaluated monthly during June, July, and August on a scale of 1(Poor) to 5(Excellent). These ratings measured the performance of the plant variety in terms of growth rate and uniformity, bloom abundance and color, heat tolerance, pest and disease resistance, and overall landscape appeal.

After two years of lower than normal rainfall and higher than normal temperatures, both Knoxville and Jackson experienced temperatures closer to the historical norm and higher than normal rainfall. View detailed 2014 weather and historical comparisons.

As always, we wish to recognize the generous monetary, supply and seed/plant donations provided by numerous horticultural companies. We greatly appreciate their support of the annual herbaceous plant trial program.

Reports from Previous Trials:

(All of the following reports and presentations are PDF files)