Winterizing Tree Ferns: Essential Tips to Shield These Tropical Beauties

Tree ferns stand out as stunning architectural plants, adding a lush tropical feel to any garden. However, they are not fully frost-tolerant and often require protection during the winter months in various climates.

The tree fern, Dicksonia antarctica, features a fibrous trunk formed by its aerial roots, topped with impressive fronds that can grow several meters long. To thrive, these ferns need ample watering in the growing season and special care to survive the chill of winter.

While working at a renowned garden in the UK, I observed how tree ferns thrived in a section called 'Fern Dell'. Each winter, we took care to insulate these ferns against frost by wrapping them in situ, creating an interesting winter display.

Winter Care for Dicksonia Tree Ferns

With thousands of fern varieties worldwide, some are hardy enough to survive outdoors without care, while others are more delicate and suited for indoor settings.

Tree ferns fall into the category of those needing winter protection. Commonly found in tropical gardens, let's explore the best ways to safeguard these ferns during colder months.

Ways to Protect Tree Ferns in Winter

Tree ferns can endure brief temperature drops to 23°F, but extended cold spells can harm them. If you reside in a US hardiness zone with severe winters, it's wise to safeguard your tree ferns. You can either leave them outside wrapped or bring them indoors for the season.

The optimal way to shield tree ferns from frost, as practiced in the garden mentioned earlier, is to keep them planted in the ground. Some gardeners opt not to wrap the fronds, viewing them as replaceable, but we preferred a method that enveloped the entire plant, fronds included. Before wrapping, remove any damaged fronds to prevent disease.

According to a gardening expert, late fall is the best time to start winter preparations, ideally before the first hard frost. She emphasizes that protecting the crown is crucial. Using straw or dead fronds can fill the crown effectively.

Additionally, wrapping the trunk with hessian or fleece secured with twine is beneficial. Be sure to remove the winter cover as spring arrives to allow the fern to grow again.

My experiences align with these recommendations. We used horticultural fleece from various retailers along with hessian to insulate the crown, ensuring it stays warm enough for new growth come spring. More fleece wrapped around the trunk added further protection from rain, all secured with poles and twine.

While many gardeners prefer leaving their tree ferns in the ground, some choose to move them to a frost-free location, like a greenhouse. If you have adequate space and live in an area with extremely cold winters, this can be a viable option since tree ferns have relatively small root systems.

Plants can be dug up and potted in a frost-free area. However, protecting them outdoors is often simpler and less labor-intensive.

Besides wrapping or relocating tree ferns, an experienced gardener suggests a proactive approach to help them endure winter. He recommends a monthly feeding of 1 oz (28g) per square meter of sulfate of potash from May to September to strengthen their frost resistance.

This approach has proven effective, and a suitable product can be found online.

FAQs

Can tree ferns survive winter?

Tree ferns can survive winter if adequately protected in colder regions. They can withstand some frost, but safeguarding the crown from cold damage is essential.

Can tree ferns recover from frost damage?

If the crown remains intact, tree ferns can recover. Healthy crowns will produce new foliage in spring, while damaged fronds can be removed and replaced. It's typical for fronds to brown in winter, but the key concern is to keep the crown safe from frost.

Tree ferns thrive in shaded areas, making them excellent choices for challenging north-facing gardens. While they can tolerate sunny spots, they will require more frequent watering during hot summer days. You can find tree ferns at reputable nurseries or online, such as this Dicksonia antarctica available at Walmart.