We are pleased to have guest author, Dr. Alison O’Connor, Horticulture Agent at Larimer County Extension, contribute a timely article on tomatoes. Thank you Alison!

Think Tomatoes!

It’s official. Punxsutawney Phil saw his shadow and there’s more winter ahead. For those who’ve lived in Colorado for a few years, you know our snowiest months are usually February and March, but gardeners can use these days to dream of spring. Since 2019, the Larimer County Master Gardeners, under the supervision of fellow CMG Jon Weiss, have conducted tomato trials, trying to determine some of the most fruitful (and tasty) tomatoes for northern Colorado.

Jon and his cadre of volunteer cohorts designed and managed two trials: The first was an in-ground study conducted in 2019 and 2021 at the ARDEC-South Experiment Station in Fort Collins. The other was a container study at the CSU Annual Trial Gardens on Remington Street.

Field Trials

With a pause in field research in 2020 due to Covid, this study started in 2019 and was replicated in 2021. Jon selected 12 tomato varieties, both hybrid and open-pollinated selections. There were three replications with five plants per replication of each variety. In working with the elements and challenges of an outdoor field study, the crops experienced all types of weather (including hail) and varying lengths of growing seasons. In addition to collecting data on when the tomatoes started maturing, average size of fruit and total yield was documented. New Girl was the earliest maturing variety and had the highest fruit yield for 2019 and 2021. While fruit size for this variety is small, those looking for high yields and large fruit may want to consider Carbon and/or Big Beef.

But how do they taste? Jon conducted taste-test studies with all 12 of the tomato varieties (thank you taste-testers!) and New Girl had an average flavor of 3.3 (out of 5) for the average of the two growing seasons.

Container Trials

In thinking about gardeners with smaller spaces, Jon also selected tomatoes to grow in containers. Tomatoes were not staked and left to grow in their natural habit, which was variable among the three varieties. Cherry Falls was an early maturing variety with a compact, somewhat open growth habit. Totem had a dense growth habit and was the latest maturing of the three. Patio Choice Yellow was as early as Cherry Falls, with larger fruit and higher yield.

So, if you like yellow tomatoes with big yield (an average of eight pounds of fruit per plant), Patio Choice Yellow might be a good one to add to your garden this summer.

It should be noted that all harvested fruit was donated to the Larimer County Food Bank, with several hundred pounds donated in 2021. For more results, check out the summaries here.

Going forward, Jon is planning to move on from tomatoes and will be conducting a sweet pepper trial in 2022, including bell peppers and “lunch box” types. Our thanks and appreciation to the staff at ARDEC-South and the CSU Annual Trials Gardens: Drs. Mark Uchanski and Jim Klett, Jane Davey and David Staats for their support of these trials.

For more information, check out the 2021 Larimer County Master Gardener Container Tomato Trials and the 2019 & 2021 Larimer County Master Gardener Tomato Trials.