Understanding Temperennials

Plant labels can be our best friend—they help us understand bloom times, size, care and light requirements. What they don’t always explain, though, are the in-depth details of how that plant will fare in one environment versus another. 

Every plant follows the same general process within its lifecycle. Annuals begin and end that cycle in a single growing season, whereas perennials can live anywhere from three years to an entire lifetime (peonies, they’re delightful!). There’s a caveat with perennials that are native to warmer climates, though, and we like to refer to the term ‘temperennials’ when describing these particular plants. 

What are Temperennials? 

Also often referred to as ‘tender perennials,’ the temperennial is, in essence, perennial in some places but not in others. Often tropical and native to a warmer climate, temperennial plants are not fit to withstand the cold temperatures experienced in more Northern growing zones. They tend to only be able to winter in zones 7 or higher. This doesn’t mean that you can’t plant them, or keep them for their entire perennial life cycle in cooler climates, though—it just means they need a little extra special care and attention once the temperatures start to dip. 

Some of Our Favorite Temperennials 

Dahlias: The star of the show in many gardens, dahlias are one of the most dazzling temperennials around. Native to the mountains of Northern Mexico, dahlias are generally not hardy above zone 8.

Calla Lilies: While often treated as a one-time annual beauty in cooler climates, calla lilies can actually be kept year-round if you treat them right. Their trumpet-like blooms and sword-like foliage bring such elegance to the garden; why wouldn’t we want to keep them blooming? 

Tender perennials, or temperennials, should only be planted in late spring or early summer once the risk of frost has completely passed. Ideally, if you can wait until the soil has warmed up to about 65 degrees, you will have a better chance of them reaching their full potential.

Elephant Ears: Alocasia, Colocasia, and Caladium are all tropical plants grown for their show-stopping foliage. While they thrive in warmer, humid climates that better replicate their native environment, those in cooler climates can still enjoy some tropical vibes by replanting them each year. 

How to Plant & Care For Temperennials in Cooler Climates

Tender perennials, or temperennials, should only be planted in late spring or early summer once the risk of frost has completely passed. Ideally, if you can wait until the soil has warmed up to about 65 degrees, you will have a better chance of them reaching their full potential. Keep your soil moist as the plant establishes itself, and adjust your watering schedule based on the plant’s ideal conditions. 

Of course, if you live in a warm enough climate for them to overwinter, then you treat your temperennials as perennials! But, if you are in a cooler climate, once the fall rolls around, you have two options with temperennials. You can treat them as annuals or pull them up and save the bulbs for next season. Generally, if you hope to overwinter, say, your dahlias, your cue to pull the tubers out of the ground would be when their foliage starts to brown. 

Be careful when you dig bulbs or tubers up by going well into the soil under the plant, loosen it gently, and lightly shake the dirt off of them before leaving them somewhere shady to dry. Avoid washing or rinsing bulbs as they might rot. Once the bulbs have dried, you can store them in a cool (40 – 50 degrees F), dry area for the winter.  Avoid storing near fruits or vegetables as the ethylene gases from them may cause the blooms of the bulbs not to form. If you hope to overwinter a plant that is not grown from a bulb, you can bring them indoors as potted plants and let them go dormant for the winter. 

Temperennials bring immense variety and interest to gardens, regardless of what zone you are planting in. And, by taking the proper steps, you can keep them blooming for years to come. If you’re on the hunt for spring or summer flowering bulbs, check out our extensive online catalogue and be sure to get your orders in early before they sell out!