Air-Prune Beds

“An air-pruning propagation system is a low-cost, efficient method of propagating cuttings, seedlings or container plants for restoration projects. Air pruning happens naturally when roots are exposed to air in the absence of high humidity. The roots are effectively 'burned' off, causing the plant to constantly produce new and healthy branching roots. If roots are not exposed to air, they continue to grow around the container in a constricted pattern. The roots may spiral, twist, kink or become strangled.

When the plant is later installed it will likely fail to establish a normal root structure, and instead will have reduced uptake of water and nutrients. ... Healthy, highly branched root structures allow a plant to more efficiently uptake water and nutrients while increasing growth and overall plant health.” — from Walker, 2005

EdibleAcres. 2022. Air Prune Boxes - Version 2 - INCREDIBLE tree growing system. Video. Retrieved from youtube.com/watch?v=ab67eKU0ZeY.

EdibleAcres. 2019. 1000+ Trees... 1 Parking Space. Video. Retrieved from youtube.com/watch?v=sO5ETzQqttg.

From the video's description: “I'm excited to share a system that is proving to be quite productive so far. The basic idea is to create long lasting beds made of non-toxic materials to grow incredibly healthy and valuable trees on our most marginal space: our driveway! depts.washington.edu/propplnt/Chapters/air-pruning.htm: Air prune technical details and value. I encourage you to research and learn about this system as a way to grow very well adapted and heartily rooted young trees to set out in the field or sell.”

EdibleAcres. 2019. Chestnut Seeds Are Sprouting: Nursery work must begin!. Video. Retrieved from youtube.com/watch?v=gB9mTPs6uv0.

From the video's description: “A fair bit of the tree seeds we've stored in our root cellar are starting to wake up after a nice long winter. It's great to see they are so incredibly viable and alive, but the timing is a little tough as the ground outside is still frozen and snow covered! I'm scrambling to make 1'x2' movable, strong 'air prune' boxes that I can plant these seeds into so their roots can continue to develop in the right direction and get established and ready to grow, and then putting them back in the root cellar so they can remain cool and slow in the process. Hoping spring comes soon since these boxes are starting to pile up!”

EdibleAcres. 2019. Air Prune Beds: The Unboxing! Video. Retrieved from youtube.com/watch?v=W0k8OjvUH4g.

From the video's description: “More detailed discussion of the 2' x 4' boxes we built to sit on our driveway for the summer. Air prune beds are an incredible way to grow trees, shrubs, etc, on very marginal spaces, or in places temporarily. Perhaps you are renting, or are in school, or have access to a space this year but not next, etc. This basic design approach can help you generate a tremendous number of incredibly high valued plants and put things back how they were when you are done! We're hoping this can be a useful idea for anyone interested in growing MANY trees to either earn some money where they live, or kick start a beautiful food forest for very little investment.”

Julia Walker. 2005. Guidebook for Native Plant Propagation: Development and construction of an air-pruning propagation bench, and its proper use. In 'ESRM 412: Native Plant Production'. University of Washington, College of Forest Resources. Retrieved from depts.washington.edu/propplnt/Chapters/air-pruning.htm