Wicked Witch-Hazels

Contributed by Jon L. Peter, Curator & Plant Records Manager

The Hamamelidaceae family contains some of our finest trees and shrubs. From the intricate bark of Parrotia (Ironwood), the pendulous delights of Corylopsis (Winter-hazel), the impressive year round interest of Fothergilla (Witch-alder) and of course, the infamous Hamamelis (Witch-hazel). Currently in RBG, we have 161 individual plants represented by 38 taxa (types: species, hybrids and cultivars) in this family of plants.

At RBG, witch-hazels are one of the last shrubs to flower in the year (Hamamelis virginiana is known to flower in late October through December each year) and also the first shrubs to flower in the year (Hamamelis ×intermedia cultivars tend to flower in January through April). Mild temperatures this past winter meant that we had examples of witch-hazels flowering November through to March. It’s quite possible that there are some still flowering in April.

In the genus Hamamelis (Witch-hazel) we have 81 individual plants represented by 27 different types in our collection. Let’s look a little closer at the phenology of RBG accession 940319*A – Hamamelis ×intermedia ‘Primavera’ – which grows in the Synoptic Shrub collection at Arboretum. This ‘Primavera’ cultivar is generally one of the later flowering of the H. ×intermedia types and features beautiful, deliciously fragrant, soft yellow flowers. This accession was at peak bloom on March 9, 2018. It flowered again on March 22, 2019 with those flowers lasting through to at least April 10, 2019. This year, it was flowering March 4, 2020 and I am sure the spring season has allowed it to continue for some time.

Collection of this phenology data dates back to at least 1750 when Linnaeus started documenting flowering times and weather conditions . This data is an important part of what public gardens across the world contribute to in order to support our understanding of plants and to identify ecological changes that may be affecting our gardens and environments.