Smart Pot research library
Research helps explain how fabric containers interact with roots, potting mix, and growing conditions. This library brings together selected studies and nursery reports from our parent company, High Caliper Growing. Each entry identifies the growing system tested so you can put the findings in context.
Above-ground fabric containers
Smart Pots and shrub roses — Texas A&M, 2006
Authors: Michael A. Arnold and Garry V. McDonald. Published in Subtropical Plant Science, volume 58; trial conducted in 2005.
Researchers compared Knock Out roses in 11-liter Smart Pots and black plastic pots using two substrates. Fabric-grown plants generally grew more and had less root circling; substrate choice influenced growth. Temperature measurements came from one particularly hot day. These findings do not establish a universal cooling amount or vegetable-yield increase. High Caliper Growing helped fund the experiments.
Read the research and methods · Open the original article PDF
Root pruning and shade trees — Oregon State, 2007
Author: James Altland, North Willamette Research and Extension Center. Published in Digger, May 2007.
This report describes container and root-pruning experiments with nursery shade trees. In the replicated comparison, maple, pin oak, and ash grown in fabric had fewer circling roots than those in plastic. Root tips touching the wall at initial potting could still develop poorly directed growth. The practical lesson concerns both container choice and careful nursery planting; it is not a recommendation to prune every houseplant’s roots or evidence for every current product configuration.
Read the nursery research report
Above-ground nursery production in Maryland — 2005
Authors: Stanton Gill and Suzanne Klick, University of Maryland. Published in Groundwork, February 2005; observations from 2002–2004.
The report discusses several production systems and a trial involving Leyland cypress and Thuja ‘Green Giant’ in above-ground Smart Pots and nursery boxes. The authors observed strong growth and limited perimeter-root injury after two winters. Subsequent landscape establishment was still to be evaluated. This small, location-specific nursery experience does not establish cold protection for all plants or climates.
Read the report and its limitations
In-ground root-control bags: a different growing system
These bags are installed in the ground for nursery or orchard production. Their root-restriction findings should not be treated as promises about above-ground Smart Pots, home raised beds, or the Transplanter.
Root restriction of apple and peach — University of Georgia, 1992
Author: Stephen C. Myers. Published in Acta Horticulturae, volume 322, October 1992.
Golden Delicious apples and Winblo peaches were grown with different volumes of in-ground fabric root restriction. Restricted trees developed smaller canopies. Some measures of yield efficiency increased relative to tree size, but peach fruit count, total fruit weight, and mean fruit weight were not increased in the third season. Efficiency per unit of tree size is different from a larger total harvest.
Fertilization and holly roots — Clemson, 1992
Author: James B. Aitken. Published in the SNA Research Conference proceedings, volume 37.
This field-production study examined Nellie R. Stevens holly, fabric root-control bags, and fertilizer treatments over three years. Bag-grown plants developed heavier, more compact root balls. Fertilizer delivery affected root weight, and installing the bags required additional labor. The results concern this in-ground nursery system, not a universal fertilizer recipe for home containers.
Use the evidence in your own garden
Choose an appropriate container size, potting mix, planting method, and watering routine for your crop. Historical research describes the products and conditions tested at that time; current products and your growing conditions may differ.
Find a Smart Pot for your next project · Explore High Caliper Growing’s research archive
Smart Pot® is the original fabric planter, made in the USA since 1984. From home gardens to professional growing, we’re here to help.
Anything else is just a pot.