How to Grow Franklinia Trees

Closeup of a Franklinia flower
Franklinia alatamaha flower in bloom at The Arboretum at UUCCH

 Les Engels

In This Article

Franklinia alatamaha, commonly called the Franklin Tree, lets you grow a direct connection to our nation’s rich botanical history in your garden. It also helps with the conservation of a beautiful tree that is extinct in the wild. 

In 1765, the Philadelphia botanists, John Bartram, who was appointed “Royal Botanist” for the colonies and his son William, discovered several shrubs growing along the Altamaha River while on a scientific expedition in Georgia. A few years later William returned to the area to study the plant and thought it to be from the species Gordonia.  This was not the case and, after closer study, the tree, with larger more fragrant blooms, was discovered to be its own species.

William collected seeds on yet another trip to the area in 1777 and attempted to cultivate the seeds after he returned home from his travels at his family’s botanical garden. It was not until 1781 that he was able to successfully cultivate the seed

The Bartram family had their garden in Philadelphia, outside of the city. It is now in the Elmwood Section of Southwest Philadelphia and still open to the public for tours. The garden's proximity to the home of Benjamin Franklin allowed a close friendship to kindle between Franklin and John Bartram. In honor of this friendship, William named the new species Franklinia after his father’s dear friend, Ben Franklin.

Sadly, the last time the tree was seen in the wild was in 1803 by John Lyon, another famed botanist of the day. Lyon also worked in the epicenter of the early American botany world in Philadelphia.

The extinction of the tree is a great mystery, but with the speed that it disappeared, we know that it was already heading towards extinction. Planting a Franklin Tree today helps with the conservation of this species and continues the education about an amazing story in our country’s amazingly rich botanical history. Every Franklin Tree that is planted today is a direct descendant from the original seed collected by William Bartram.

For those not so interested in history and trivia, the trees stunning look will appeal. The Franklin Tree is a small deciduous tree in the tea family that grows to about 20 feet with a single trunk, or smaller if multi-stemmed. The beautifully fragrant flowers are three to four inches wide with five cup-shaped white petals surrounding a bundle of bright yellow stamens. The fall color of the foliage ranges from a warm burgundy to a dark sienna, which contrasts strikingly against the pewter of the bark and branches.

This historic tree makes a statement all year round, with its gorgeous blooms and its fiery autumn colors. The Franklinia deserves a place of prominence in your landscape whether for its aesthetics or its history.  

Botanical Name  Franklinia alatamaha
Common Name Franklin Tree
Plant Type Tree 
Mature Size 10-20 feet tall, 6-15 feet wide
Sun Exposure Full Sun to Part Shade
Soil Type Rich Organic, Moist but well drained
Soil pH Acidic
Bloom Time Late July to Early September
Flower Color White
Hardiness Zones 5 to 8
Native Range Extinct in the wild, was Southeast Georgia

Franklinia Care

 Franklinia are hard to grow. This can be attributed to any number of reasons, from lack of soil and temperature adaptability to moisture issues in the soil. As with any plant, putting in the effort and knowing the ideal conditions will eventually provide the desired results.  

Finding a plant will most likely take some searching online or, if you are lucky enough to live near Philadelphia, occasionally Bartram’s Gardens. This non-profit has plant sales and makes them available to help support the site.

Once you have your plant, site selection, soil testing, and preparation are recommended. This is a rare tree that, as mentioned earlier, is deserving of a prominent location. Your soil should meet the standards stated below and amended properly before you consider planting. If your soil consists of a lot of clay add organics to it during planting. 

To plant your tree dig the hole twice as wide as the container or rootball is deep. Remember to plant your tree shallow. Plant the roots not the trunk of your tree. Add your organics along with a root growth stimulator and refill the hole with an abundant amount of water. Cover with mulch up to two to three inches out to the dripline, but not allowing the mulch to touch the trunk.   


The Franklinia needs full to part sun with full sun leading to deeper richer fall foliage.


The tree prefers a humus-rich, acidic soil with good drainage, much like the soil demands of a Rhododendron.


Maintaining the tree’s moisture is important if the soil allows for good drainage. It will not tolerate standing water but does not tolerate dry soil either and will need regular watering during drought conditions.

Temperature and Humidity

The tree’s hardiness range is between zone 5 and 8. If you are in zone 5, it is recommended you search out the cultivar Franklinia alatamaha ‘Wintonbury’ which is known to be more frost hardy. It should be sheltered in the northern climates from cold winds. 


Give your tree a yearly fertilizer treatment in early spring with an acidic based soluble fertilizer. Your tree will benefit from an annual feeding of magnesium sulfate given at one tablespoon per gallon of water at the same time.