Perennials live to grow another year

Madelyn Meier

Nebraska News Service

With the 20 below-freezing temperatures that swept Nebraska this winter, most gardeners had a concern: if previously planted perennials would grow this year.

For plant lovers and gardeners alike, the snow layers have acted as good insulation against extreme temperatures, protecting most herbaceous perennials.

“Snow cover helped keep soil temperatures from reaching the extreme lows, so the roots should still be in good condition and resume normal growth in the spring,” said Kyle Broderick, extension educator and plant diagnostician at the University of Nebraska Lincoln’s Plant and Pest Diagnostic Clinic.

Overwintering buds also mature and become covered by protective scales that decrease injury.

“Luckily, most landscape plants can tolerate cold spells, especially when the cold isn’t late in the fall or early spring when plants haven’t prepared for winter or started spring growth,” Broderick said. “When woody trees, shrubs and herbaceous perennials are allowed to harden off and go dormant in the fall, they can often tolerate cold temperatures.”

According to Broderick, gardeners should plant things that are well adapted to Nebraska’s climate based on the USDA Plant Hardiness Zones. Lincoln is in the 5b zone meaning that plants bred for this area should be able to tolerate -10 to -15 degrees Fahrenheit.

“Plants that are better adapted for warmer climates like zone 6 and above are likely to see more severe injury due to the cold,” Broderick said.

Kelly Feehan, horticulture extension expert, said the melting of this protective layer of snow might actually cause more damage to perennials than the previous negative temperatures.

“In reality, the above 60 degree temperatures we are having in March might have more of an impact,” Feehan said. “It melted the insulating snow layer and caused artificial warming that has the potential to cause some plants to begin to break dormancy and become susceptible to cold weather.”

As the snow melts and spring takes full bloom, greenhouses and garden centers will begin seeing high sales in all areas, especially with the COVID-19 pandemic creating a demand for gardening and garden materials.

“It is reported that over 16 million people started to garden this past year due to the COVID pandemic,” Feehan said. “Last year, this led to some plants not being available as garden centers ran out of available transplants and seeds.”

Although it makes items more difficult to find, this surge in gardening boosts both the economy and people’s curiosity.

“This increase will help the green space industry economically and it will lead to an increase in garden and landscape-related questions for UNL Extension,” Feehan said. “In Nebraska, we developed the Grow Big Red Zoom series to assist current and new gardeners with their questions.”

Whether people are picking up tools for the first time or have been practicing for years, gardening brings something for everyone.

“My favorite part is sitting back and viewing my plants and seeing the diversity that they bring to my yard,” Feehan said. “It is fascinating to watch bees and butterflies flit from flower to flower, gathering pollen.”

Outside of enjoyment, gardening contains benefits to improve both people and the globe.

“Gardens and landscapes provide many benefits from ecosystem services to providing people-plant connections that improve mental health and strengthen communities in many ways,” Feehan said.

For gardening-related questions, visit https://communityenvironment.unl.edu/