Honey Locust Seed

Honey locust is fun and easy to grow from seed. They are a vigorous and fast-growing tree. Most of our seed stock comes from incredible mother trees at the remnants of John Hershey’s nursery in Downingtown PA. See below for a full list of honey locust seed sources we have available. If you don’t know about John Hershey you can read more at the article linked below but I will give you the brief version here.

John was a giant of the tree breeding world in the 1900s. His nursery was often referred to as America’s number 1 tree crops nursery. John collected improved genetics for (mostly native) tree crops from all across the country. His selection criteria were mainly around increased food value for humans and livestock. In the case of honey locust John seemed most interested in trees which produce heavy crops of thick sugary pods. There was also interest in finding trees which do not produce thorns. When John found such trees, he brought back seed and scion wood to his nursery in PA. There he grew out seedlings and grafted the scion wood onto existing rootstock. By the time he died his 60-acre(ish) farm was a legendary collection of genetics. Sadly, this farm was not protected and more than half of the trees have been cut down to allow for construction of suburban houses and other infrastructure. Some trees remain spread across the landscape. It is from some of those trees that our seed came.

Across from the Quaker Friends Meeting House in Downingtown there is a row of trees which include several honey locusts. We gathered pods from each of the trees in this row. All trees in this row produce thick juicy pods packed with sugar, although some seem to bear heavier than others. The soil in this area is compacted and neglected and some trees have more access to sunlight than others which could account for the dispersion of yield. 

A note on thorn-lessness: 

I (Nick) recently learned a bit more about how thornless traits in honey locusts work. To my knowledge most of the Hershey trees are technically thorny even though the trees do not have thorns. I know that sounds crazy, hang with me for a moment though. Some honey locust trees do not produce thorns but most do. The size and quantity of thorns can vary from tree to tree. Most thorny honey locusts do not make thorns at the top of the tree. If scion wood is collected from the thornless top branches and grafted onto rootstock the resulting grafted tree will not express thorns. But because the original tree that donated the scion wood had thorns the seeds from these grafted trees will have genetics for thorns. I do not know the variety names of the trees at Hershey's site but my current understanding is that they are grafted and most will have genetics for thorns. I am fairly certain that some of these trees may be truly thornless but I have no way of knowing which is which. 

With that said these are valuable genetics that John and many others fought hard to preserve. Desirable traits such as high sugar content in pods and perhaps some thornless-ness will surely be passed on to many of the offspring.  We are confident that these seeds are worth growing. Around the Hershey farm you can find what look to be wild planted honey locust, many of which have no thorns but often have less sugary pods by comparison. I assume these came from John’s mother trees and planted themselves. 

The calorie yield from the sugar filled pods of the grafted trees at Hershey's site is truly baffling. They are tasty and good for humans but most folks seem more interested in their value for feeding animals. Pretty much all grazing animals go crazy for the pods. The trees provide a dappled shade which does not interfere with grass growth in a pasture setting. The pods are ripe during mid winter when there is little other forage available. All of these traits make them a perfect silvopasture species. 

Hershey row refers to the grafted, thornless trees with incredibly thick pods across from the Quaker Meeting House. To my knowledge these were definitely planted by Hershey. 

Wild Hershey refers to some trees behind the Quaker meeting house that appear to be wild planted trees. The trees I collected from in this bath were thornless but had much less sugar content in the pods. Trees were loaded with a silly number of pods. 

Honey locust is a highly adaptable and vigorous tree native to the east coast of the US. Livestock enjoy grazing the leaves and pods if they can access them. These trees respond well to coppicing. There is some debate as to whether honey locust can fix nitrogen in the soil. Many scientific sources state that honey locust does not develop root nodules that are present in other species that fix nitrogen via a relationship to rhizobium bacteria. There are however other ways that plants can fix nitrogen, rhizobium is not the only bacteria capable of this feat. If you would like to learn more about other ways that plants can fix nitrogen, we recommend looking at the research being done by Dr. James White at Rutgers University. Honey locust have an amazing yellow fall color.

Growing Instructions 

Most resources say that honey locust seed requires scarification to germinate. This can be accomplished through an acid treatment (which I can’t comment on as I have no experience going that route) or a hot water bath. For more information on using acid to scarify seeds we recommend the US Forest Service document titled 'Woody Plant Seed Manual' which is available for free online. To scarify with hot water, bring a pot of water to a boil and then turn off heat. As soon as the water stops bubbling, dump seeds into the water. Do not place seeds into boiling water, let the water cool slightly. Let soak for 12-24 hours. The water will continue to cool down as the seeds soak. The seeds are ready once they visibly swell in size from absorbing water. You will want to plant the seeds ASAP after this process. Be sure to plant after the danger of frost or protect seedlings somehow. I have also had luck sowing honey locust in the fall outdoors and letting them come up on their own in the spring but this is not advised in most sources I have read. Honey locust are desired food for many grazing animals so be sure to fence your seedlings! They dig and transplant easily at a young age

Learn more about John's work:

https://www.shelterwoodforestfarm.com/blog/2018/10/17/exploring-americas-oldest-food-forest

https://www.phillymag.com/news/2018/07/07/downingtown-food-forest-urban-farming/