The Nancy Moss Fine Native Azalea Garden

The early native azaleas are located on a level area of the arboretum bordering a red maple swamp with high dappled shade provided by tuliptrees and magnolias. This area is indicated by the number "1" on this map, dated 1941.

Early arboretum accession records - kept on 3x5" cards - indicate two Swamp Azalea (R. viscosum) plants were wild-collected in a sphagnum swamp near Little Pond, Thompson, CT, September 1, 1947 by Richard H. Goodwin, arboretum director, and K. P. Jansson, horticulturist. These plants still exist with accession numbers 47-75A and 47-81A.

Based on oral records, we know that Roseshell Azalea (R. prinophyllum) was planted in this same area during the 1940s, wild collected by H. Lincoln Foster from his property in Falls River, CT and donated to the arboretum.

During the 1970s, the native azalea collection was expanded considerably by Connecticut College Botany Professor Sally Taylor. With a deep appreciation for native azaleas, Sally would often return from personal travel with her car full of plants that she had purchased for the arboretum. When a donor stepped forward in 1978, the Nancy Moss Fine Native Azalea Garden was established.

This memorial garden ("2" on the map), which contains most of our native azaleas, is located on a west-facing slope with an appropriate combination of sun and shade at different times of the day.

This map illustrates the overlapping natural ranges of the native azaleas. Which azaleas naturally occur in the Connecticut College Arboretum? Click on the search button (spyglass) and enter New London CT to find it on the map. Click on the location to view some basic information about the species that are native to the arboretum. Use the > button to see more than one species.

Most of these ranges were digitized from illustrations shown in Clarence Towe's  American Azaleas  published by Timber Press in 2004.

While all azaleas are Rhododendrons by genus, not all Rhododendrons are azaleas.

Here are some simple ways to (with a few exceptions) distinguish between azaleas and the plants commonly called rhododendron:

1. True rhododendrons are usually evergreen, while azaleas are usually deciduous.
2. True rhododendrons usually have flowers with 10 or more stamens, while azaleas have 5-7 stamens.

For more definite identification, use a deciduous key to narrow down through characteristics like flower color, bloom time, leaves, seed capsules, and presence or absence of hairs and glands on flower parts.



Depending on the specific species, azaleas can bloom between late April and early August. See which azaleas are blooming in any given timeframe using the maps below, or see how they compare with each other in this phenology diagram from 1984. Note that while relative succession of blooms has remained the same, the season has slightly shifted due to changing temperatures.

Expand the maps below to see what azaleas are blooming in a given month - click on a point for more information.

GROWING AZALEAS

Azaleas are relatively easy-care additions to a garden. If you'd like to grow your own, here are some things to keep in mind:

• Well-drained soil that is able to maintain moisture - like the acidic sandy loam we have at the arboretum - is best.
• Azaleas grow best in partial shade, but can tolerate sun for part of the day
• If you'd like to prune your azaleas, do so in spring right after they flower - that way you don't prune away buds for the next year's flowering.
• Azaleas' wild habitats are within woodlands, so application of organic matter is always helpful to mimic native conditions. If you have to mulch, use leaf mulch or natural bark mulch that will decay naturally.

Image shows newly-planted azaleas in the Fine Garden ca. 1982 - note the generous spacing to account for final size and layer of natural bark mulch.

USDA Hardiness Zones

The southern New England climate is well-suited for deciduous native azaleas. According to the 2023 USDA Plant hardiness Zone Map, we are in zone 7A. Since New London is coastal, the arboretum (marked by the star) is within one of the mildest areas of New England. Summers are frequently hot and humid, and winters are cool with a mix of snow and rain. 

Find the USDA Plant Hardiness Zone for anywhere in the contiguous US states by using the location search button (spyglass) and clicking on the map, or use the location circle in the bottom right to zoom directly into your current location.