What Substrate Is

Sources & further reading

Altland, J. E., Locke, J. C., & Krause, C. R. (2014). Influence of pine bark particle size and pH on cation exchange capacity. HortTechnology, 24(5), 554–559. https://doi.org/10.21273/HORTTECH.24.5.554

Altland, J. E., Owen, J. S., Jr., & Gabriel, M. Z. (2011). Influence of pumice and plant roots on substrate physical properties over time. HortTechnology, 21(5), 554–557. https://doi.org/10.21273/HORTTECH.21.5.554

Altland, J., & Bugbee, B. (2026). The limits of sustainability of peat as a soilless media for agriculture. Frontiers in Plant Science, 17, Article 1856037. https://doi.org/10.3389/fpls.2026.1856037

Argo, B. (2004). Understanding pH management and plant nutrition, Part 4: Substrates. Journal of the International Phalaenopsis Alliance, 13(3). https://staugorchidsociety.org/PDF/IPASubstrates.pdf

Argo, W. R., & Fisher, P. R. (n.d.). Understanding plant nutrition: Fertilizers and media pH. Greenhouse Grower. https://www.greenhousegrower.com/?p=4049

Basiri Jahromi, N., Fulcher, A., & Walker, F. (2019). What is biochar and how different biochars can improve your crops (W 829). University of Tennessee Extension. https://woodsubstrates.cals.ncsu.edu/wp-content/uploads/sites/39/2020/02/what-is-biochar.pdf

Bilderback, T. E., Warren, S. L., Owen, J. S., Jr., & Albano, J. P. (2005). Healthy substrates need physicals too! HortTechnology, 15(4), 747–751. https://doi.org/10.21273/HORTTECH.15.4.0747

Bilderback, T., & Fields, A. (2008). Measuring air-filled porosity for container substrates. Combined Proceedings International Plant Propagators’ Society, 58, 129–131. https://ipps.org/wp-content/uploads/2025/03/58_021.pdf

Bilderback, T., Boyer, C., Chappell, M., Fain, G., Fare, D., Gilliam, C., Jackson, B. E., Lea-Cox, J., LeBude, A. V., Niemiera, A., Owen, J., Ruter, J., Tilt, K., Warren, S., White, S., Whitwell, T., Wright, R., & Yeager, T. (2013). Best management practices: Guide for producing nursery crops (3rd ed.), Section 2: Container nutrition management practices. Southern Nursery Association. https://nc1186.spes.vt.edu/?p=104

Camberato, D. M., Lopez, R. G., & Mickelbart, M. V. (2009). pH and electrical conductivity measurements in soilless substrates (HO-237-W). Purdue Extension. https://www.extension.purdue.edu/extmedia/HO/HO-237-W.pdf

Carlile, W. R., Cattivello, C., & Zaccheo, P. (2015). Organic growing media: Constituents and properties. Vadose Zone Journal, 14(6), Article vzj2014.09.0125. https://doi.org/10.2136/vzj2014.09.0125

Chen, J., & McConnell, D. (2020). Compost-formulated media for foliage plant production (ENH873/EP129). UF/IFAS Extension. https://edis.ifas.ufl.edu/publication/EP129

Chen, J., McConnell, D. B., Henny, R. J., & Everitt, K. C. (2015a). Cultural guidelines for commercial production of interiorscape Aglaonema (ENH957/EP160). UF/IFAS Extension. https://edis.ifas.ufl.edu/publication/EP160

Chen, J., McConnell, D. B., Henny, R. J., & Everitt, K. C. (2015b). Cultural guidelines for commercial production of interiorscape Anthurium (ENH956/EP159). UF/IFAS Extension. https://edis.ifas.ufl.edu/publication/EP159

Colucci, I. (2022, March 7). How to diagnose plant nutrient deficiencies using leaf symptoms. SoilNOW, Cornell Cooperative Extension. https://blogs.cornell.edu/soilnow/ph/how-to-diagnose-plant-nutrient-deficiencies-using-leaf-symptoms

Concklin, M., & Marquesen, S. (2026, February 23). Repotting houseplants. Penn State Extension. https://extension.psu.edu/repotting-houseplants

Cox, D. (1995). Water quality: pH and alkalinity [Fact sheet]. UMass Extension Greenhouse Crops and Floriculture Program. https://ag.umass.edu/greenhouse-floriculture/fact-sheets/water-quality-ph-alkalinity

Cox, D. A. (2019). Methods of greenhouse media testing and how they differ [Fact sheet]. UMass Extension Greenhouse Crops and Floriculture Program. https://ag.umass.edu/agriculture-food-environment/greenhouse-floriculture/fact-sheets/methods-of-greenhouse-media-testing-how-they-differ

Criscione, K. S., & Holliday-Goulart, A. (n.d.). Properly watering container houseplants (SPES-804P). Virginia Cooperative Extension. https://www.pubs.ext.vt.edu/content/pubs_ext_vt_edu/en/SPES/spes-804.html

Durand, S., Jackson, B. E., Fonteno, W. C., & Michel, J.-C. (2021). The use of wood fiber for reducing risks of hydrophobicity in peat-based substrates. Agronomy, 11(5), Article 907. https://doi.org/10.3390/agronomy11050907

England, K. M., Camberato, D. M., & Lopez, R. G. (2012). Water-soluble and controlled-release fertilization (HO-251-W). Purdue Extension. https://www.extension.purdue.edu/extmedia/HO/HO-251-W.pdf

Evans, M. R. (n.d.). Unit 7: Substrates [Greenhouse management online course]. University of Arkansas. https://greenhouse.hosted.uark.edu/Unit07/Printer_Friendly.html

Everett, T. L., & Nelson, P. V. (1996). Does perlite play a role in fluoride toxicity of floricultural crops? N.C. Flower Growers’ Bulletin, 41(4). https://hortscans.ces.ncsu.edu/uploads/d/o/does_pea_53ff9244b7e3a.pdf

Fields, J. S., & Owen, J. S., Jr. (2021). Substrate stratification: Layering unique substrates within a container increases resource efficiency without impacting growth of shrub rose. Agronomy, 11(8), Article 1454. https://doi.org/10.3390/agronomy11081454

Fonteno, W. C., Bailey, D. A., & Nelson, P. V. (1995). Properties of greenhouse substrates. N.C. Flower Growers’ Bulletin, 40(4), 1–8. https://hortscans.ces.ncsu.edu/uploads/p/r/properti_53ed0ad57a574.pdf

Glatzel, S., & Rochefort, L. (2017). Growing Sphagnum: Foreword. Mires and Peat, 20, Article 00, 1–3. https://doi.org/10.19189/MaP.2017.OMB.276

Grifasi, N., Ziantoni, B., Fino, D., & Piumetti, M. (2025). Fundamental properties and sustainable applications of the natural zeolite clinoptilolite. Environmental Science and Pollution Research, 32(48), 27805–27840. https://doi.org/10.1007/s11356-024-33656-5

Jackson, B., Kraus, H., & Bilderback, T. (2010). What to do when pine bark runs short: Physical properties of pine bark alternatives. SNA Research Conference Proceedings, 55, 413–415. https://woodsubstrates.cals.ncsu.edu/wp-content/uploads/sites/147/2020/12/what-to-do-pine-bark-short.pdf

Jones, C., & Olson-Rutz, K. (2016). Plant nutrition and soil fertility (Nutrient Management Module No. 2, 4449-2). Montana State University Extension. https://landresources.montana.edu/nm/documents/soilmodulepdf/4449-2.pdf

Kučera, A., Volánek, J., Tomášová, G., Holík, L., Balková, M., Vichta, T., Samec, P., Rosíková, J., & Vranová, V. (2025). Substrate enrichment with clinoptilolite: Limits and possibilities for container-grown seedling propagation. Journal of Soil Science and Plant Nutrition, 25, 10299–10312. https://doi.org/10.1007/s42729-025-02794-1

Langenfeld, N. J., Skabelund, H. A., Heins, R., & Bugbee, B. (2024). Advantages of a novel in situ pH measurement for soilless media. Frontiers in Plant Science, 15, Article 1334328. https://doi.org/10.3389/fpls.2024.1334328

Lopez, R. G., Mickelbart, M. V., & Pasian, C. (2010). Alkalinity management in soilless substrates (HO-242-W). Purdue Extension. https://www.extension.purdue.edu/extmedia/HO/HO-242-W.pdf

Lura, P., Bentz, D. P., Lange, D. A., Kovler, K., & Bentur, A. (2004). Pumice aggregates for internal water curing. In Concrete science and engineering: A tribute to Arnon Bentur (pp. 137–151). RILEM.

Maillard, A., Diquélou, S., Billard, V., Laîné, P., Garnica, M., Prudent, M., Garcia-Mina, J.-M., Yvin, J.-C., & Ourry, A. (2015). Leaf mineral nutrient remobilization during leaf senescence and modulation by nutrient deficiency. Frontiers in Plant Science, 6, Article 317. https://doi.org/10.3389/fpls.2015.00317

Malík, M., & Tlustoš, P. (2025). Soilless growing media for cannabis cultivation. Agriculture, 15(18), Article 1955. https://doi.org/10.3390/agriculture15181955

McCauley, A., Jones, C., & Jacobsen, J. (2011). Plant nutrient functions and deficiency and toxicity symptoms (Nutrient Management Module No. 9, 4449-9). Montana State University Extension. https://landresources.montana.edu/nm/documents/soilmodulepdf/4449-9.pdf

McConnell, D. B., Chen, J., Henny, R. J., & Everitt, K. C. (2003a). Cultural guidelines for commercial production of interiorscape Epipremnum (ENH894/EP151). UF/IFAS Extension. https://edis.ifas.ufl.edu/publication/EP151

McConnell, D. B., Chen, J., Henny, R. J., & Everitt, K. C. (2003b). Cultural guidelines for commercial production of interiorscape Philodendron (ENH893/EP150). UF/IFAS Extension. https://edis.ifas.ufl.edu/publication/EP150

Monsalve Camacho, O. I., Luque Sanabria, N. Y., & Sánchez Rodríguez, L. Á. (2026). Nutrient chemistry in coconut-mineral mixed substrates for soilless culture. Advances in Horticultural Science, 40(2), 165–180. https://doi.org/10.36253/ahsc-18670

Mumpton, F. A. (1999). La roca magica: Uses of natural zeolites in agriculture and industry. Proceedings of the National Academy of Sciences, 96(7), 3463–3470. https://doi.org/10.1073/pnas.96.7.3463

NC State Extension. (n.d.). Chapter 18: Plants grown in containers. In Extension gardener handbook. North Carolina State University. https://content.ces.ncsu.edu/extension-gardener-handbook/18-plants-grown-in-containers

Nemali, K. (2017, August 24). Looking through the pores of a soilless substrate. Purdue University Controlled Environment Agriculture (Nemali Lab). https://www.purdue.edu/hla/sites/cea/article/looking-through-the-pores-of-a-soilless-substrate/

Nemali, K. (2018). Understanding the pores of a soilless substrate (HO-287-W). Purdue University Extension. https://www.extension.purdue.edu/extmedia/HO/HO-287-W.pdf

New Mexico State University Extension. (2003, July 26). When to repot houseplants. Southwest Yard & Garden. https://swyg.nmsu.edu/2003/072603.html

Oregon State University Extension Service. (2022, December). Peat moss harvesting releases carbon and harms ecosystems, expert warns [News release quoting L. Brewer]. https://extension.oregonstate.edu/news/harvesting-peat-moss-contributes-climate-change-oregon-state-scientist-says

Owen, J. S., Jr., & Altland, J. E. (2008). Container height and Douglas fir bark texture affect substrate physical properties. HortScience, 43(2), 505–508. https://doi.org/10.21273/HORTSCI.43.2.505

Owen, W. G. (2026). Ironing out chlorosis: Selecting and applying iron chelates correctly (e-GRO Alert 15-09). e-GRO. https://www.e-gro.org/pdf/2026-15-09.pdf

Owen, W. G., & Lopez, R. G. (2015). Evaluating container substrates and their components (HO-255-W). Purdue Extension. https://www.extension.purdue.edu/extmedia/HO/HO-255-W.pdf

Pennisi, B. V. (2022). Growing indoor plants with success (Bulletin 1318). University of Georgia Cooperative Extension. https://fieldreport.caes.uga.edu/publications/B1318/growing-indoor-plants-with-success/

Pennisi, B. V., & Thomas, P. A. (2023). Essential pH management in greenhouse crops: pH and plant nutrition (Bulletin 1256). University of Georgia Cooperative Extension. https://extension.uga.edu/publications/detail.html?number=B1256

Robbins, J. A. (2018). Growing media for container production in a greenhouse or nursery: Part I – Components and mixes (FSA6097). University of Arkansas System Division of Agriculture, Cooperative Extension Service. https://www.uaex.uada.edu/publications/pdf/fsa-6097.pdf

Robbins, J. A., & Evans, M. R. (2005). Growing media for container production in a greenhouse or nursery: Part II (Physical and chemical properties) (FSA6098-PD-4-05R). University of Arkansas Cooperative Extension Service. Reprinted in Forest Nursery Notes (Winter 2011). https://npn.rngr.net/publications/fnn/2011-winter/new-nursery-literature/growing-media-for-container-production-in-a/at_download/file

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