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Aug 24, 2022

CSU Trial Gardens Evaluation Day

Chris Fifo
Product Representative

For the first time since pre-pandemic I was able to visit the Colorado State University trial gardens on evaluation day. This is a huge event! This trial is the largest of any west of the Mississippi. The trial gardens are open to the public every day and are the second most visited site in Fort Collins. (Second only to a brewery!)

The CSU trial gardens were founded in the mid 19070s and have grown every year since. In 2000, they outgrew the original facility and were moved to their current location about a mile east – still on the CSU campus. However, the most exciting addition to this site happened in 2016 – the addition of perennials!

Though annuals are the primary focus of the trial beds with over 1,000 entries, perennials have steadily grown to 299 entries for 2022. The trial consists of a mix of first-year planted and one- or two-year overwintered perennials.

The CSU trials are valuable to me for several reasons:

• Though Fort Collins is 5b hardiness zone, it can be a rather harsh test for overwintering perennials. There are often large temperature swings in the winter, going from a foot of snow to 60°F. Add to that a very dry wind and we have a true test for “Perennials with Staying Power”.

• Two years overwintered and three years over-summered gives evaluators a true feel for perennial performance.

• Following the third summer, an exclusive group of evaluators and board members review the perennials. Those with the highest ratings are then designated as the elite “CSU Top Performers”.

As of 2021, Darwin Perennials has had many Top Performers as rated by CSU. These include:

Echinacea Sombrero® Tres Amigos
Salvia ‘Blue by You’  an AAS Winner!
Phlox Ka-Pow®
Veronica Moody Blues®
Perovskia ‘CrazyBlue’
Eupatorium Euphoria™ Ruby
Sedum Prima Angelina
Miscanthus Bandwidth

Here are a few of the varieties that stood out to me at this trial (and at other trials I have visited this year).

Nepeta Whispurr™ Blue
Whispurr Blue is an outstanding improvement upon ‘Walker’s Low’. The number and size of the panicles gives nearly complete coverage of the foliage. Plus, Whispurr Blue does not fall open in the landscape with age or after a rainfall. (Pictured above: CSU trials at-left; Smith Gardens trials at-right.)

Phlox Super Ka-Pow™
Here we can see Ka-Pow® White next to Super Ka-Pow™ Fuchsia. Super Ka-Pow are 6-8 inches taller than Ka-Pow and still pack a punch. We can see that SKP Lavender next to the Fuchsia is about seven days later to flower. All colors in the series are very well matched in size. Though Colorado conditions are not the best for mildew tolerance trials, I have seen these to be superior in resistance. After these run their course at the trials, I fully expect Super Ka-Pow to be designated a top performer.

Echinacea Artisan™ Red Ombre
This first introduction of the F1 hybrid Echinacea collection from Kieft Seed™ does not disappoint! There’s amazing flower power and strong color on these Echinacea throughout the summer heat. I saw this and Artisan Soft Orange in September last year and they were still going strong. Though I did not see it here, be on the lookout for the latest Regional AAS Winner Artisan Yellow Ombre.

Veronica Skyward™
Darwin’s new Veronica Skyward series were planted this year and are just getting going. Skyward Pink (and Blue not shown) are putting on a strong performance. The foliage is a clean, deep green that contrasts very nicely with the strong flower colors. Rest assured there are additional colors coming for the Skyward series.

I could go on (and on), but I need to wrap this up. If you are in the Fort Collins area anytime throughout the summer and fall, I highly recommend bypassing the brewery and visiting the Colorado State University trial gardens.

Tags: trials
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