Plant Review: How Well Did Those New Plants Really Do?

Well, here we are in the middle of January and what is normally an unspeakably cold month is worse this week due to what meteorologists are calling a “distorted polar vortex,” which has allowed Arctic air to spill all the way down to Florida. With air temperatures around -20°F plus wind chill making it feel like -50°F yesterday, I’ve had a few people email to ask whether our perennials here in Minnesota will survive.

Fern frost on the window in our bathroom.

I’ll give the answer I often give for any garden-related question: It depends. It helps that we have snow cover to keep soil temperatures from fluctuating a lot. And perennials rated for our Zone 4 climate should be okay down to an air temperature of -30°F (wind chill doesn’t matter). But if you put things in the ground late, as I did last year, they may not make it since they didn’t have much time to establish a decent root system. And if you didn’t water much, plants may be too drought stressed to survive.

It’s also hard to say how newer introductions will do. With so many new plants being rushed to market each year, plant trials aren’t as rigorous as they used to be. It’s possible that some of the perennials we’ve tried lately won’t be able to hack the extreme cold. And with that in mind, here is a short review of some of the new introductions I’ve tried in my gardens in the last few years. Of course, this is just my experience. Perhaps other gardeners are growing things that I’ve killed just fine. (If that’s you, please email and tell me your secrets.) And one other thing to note—I test plants in my garden for Proven Winners so there are a lot of plants from them on this list.

Oso Happy Smoothie Rose
Courtesy of Proven Winners

Rosa Oso Happy Smoothie ‘Zlesak Poly3’ PPAF

I can’t say enough great things about this rose. Bred by David Zlesak, a hort professor at the University of Wisconsin-River Falls, Oso Happy Smoothie has been in one of my backyard gardens for a couple of seasons now. As promised, it is a little over 3 feet tall, it was covered with dainty pink blooms all summer, has great form, no thorns and recovered nicely from being chomped on by rabbits last winter.

‘Midnight Marve’ Hibiscus
Courtesy of Walters Gardens

Hibiscus ‘Midnight Marvel’           

My friend, Kathleen, bought this new hibiscus from Walters Gardens for each of us this summer and, so far, it has performed beautifully in both of our gardens—hers more than mine, though. ‘Midnight Marvel‘ didn’t yet reach its purported 48 inches tall, but it may next season, and the burgundy foliage topped with red blooms make the plant absolutely stunning.

‘Sea Heart’ Brunnera
Courtesy of Plants Nouveau

Brunnera macrophylla ‘Sea Heart’

I killed this lovely brunnera from Plants Nouveau. But maybe that’s not surprising since ‘Sea Heart‘ was said to be very much like ‘Jack Frost,’ another popular brunnera that I also killed. Both brunnera were gorgeous before I killed them, I have to say. These plants are said to be easy to grow. Is it me? It must be me. How do you grow brunnera successfully?

‘Pure Joy’ Sedum
Courtesy of Walters Gardens

Sedum ‘Pure Joy’

I like sedum and have many in my gardens. ‘Pure Joy‘ from Proven Winners and Walters Gardens is doing fine. It’s alive and didn’t ask for much in the way of care. But its blooms were neither “enormous” nor interesting in the fall, as promised. So I don’t know that I would give this one high marks, though it is hardy to Zone 3 and that’s nice.

‘Cherries Jubilee’ Baptisia
Courtesy of Walters Gardens

Baptisia australis Decadence Series

Plant breeder Hans Hansen spent more than a decade crossing native false indigo species to create the Decadence Series from Proven Winners. Decadence offers everything gardeners love about baptisia in a more compact form in a variety of colors. I’m growing ‘Lemon Meringue’ and ‘Cherries Jubilee’, and have nothing but praise for both.

‘Pretty Lady Diana’ Anemone

Anemone hupehensis ‘Pretty Lady Diana’  

Japanese anemones, including ‘Pretty Lady Diana’ were still blooming in my garden in late October, which makes them a winner in my book. Blooms of Bressingham introduced this beauty a couple of years ago and though it is rated as hardy to Zone 5, it has survived winter without a problem. Thumbs up and fingers crossed that it makes it through this harsh winter.