Water, Properly
Overwatering and underwatering can produce the same droop, which makes watering harder to get right than it looks. Nine short lessons and a one-week water log take you from chasing a schedule to reading the pot instead.
0 of 9 lessons complete
- I Watering is an air-and-water problem ~6 min
- II What happens inside the pot ~8 min
- III When to water: read the substrate, not the calendar ~7 min
- IV How to water ~6 min
- V How much, how often: it's a rate, not a number ~6 min
- VI Water quality: chlorine, chloramine, and fluoride ~6 min
- VII Water quality: soluble salts, hardness, and pH ~6 min
- VIII Reading the plant: over versus under ~7 min
- IX The mental model ~10 min + field exercise
Sources & further reading
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
Davison, E. (1998). Interior plants: Selection and care (AZ1025). University of Arizona Cooperative Extension. https://extension.arizona.edu/sites/extension.arizona.edu/files/pubs/az1025.pdf
Dvorak, B. I., & Schuerman, B. M. (2025). Chloramines water disinfection: Omaha Metropolitan Utilities District and Lincoln Water System (G1704). Nebraska Extension. https://extensionpubs.unl.edu/publication/g1704/2026/pdf/view/g1704-2026.pdf
Iowa State University Extension and Outreach. (n.d.). How to care for houseplants. Yard and Garden. https://yardandgarden.extension.iastate.edu/how-to/how-care-houseplants
Kadohama, N., Goh, T., Ohnishi, M., Fukaki, H., Mimura, T., & Suzuki, Y. (2013). Sudden collapse of vacuoles in Saintpaulia sp. palisade cells induced by a rapid temperature decrease. PLOS ONE, 8(2), Article e57259. https://doi.org/10.1371/journal.pone.0057259
Owen, J. S., Jr., LeBude, A. V., Fulcher, A., Stanley, J., & Oki, L. R. (2019). Leaching fraction: A tool to schedule irrigation for container-grown nursery crops (SPES-128). Virginia Cooperative Extension. https://www.pubs.ext.vt.edu/SPES/SPES-128/SPES-128.html
Owen, W. G., & Lopez, R. G. (2015). Evaluating container substrates and their components (HO-255-W). Purdue University Extension. https://www.extension.purdue.edu/extmedia/HO/HO-255-W.pdf
Pan, J., Sharif, R., Xu, X., & Chen, X. (2021). Mechanisms of waterlogging tolerance in plants: Research progress and prospects. Frontiers in Plant Science, 11, Article 627331. https://doi.org/10.3389/fpls.2020.627331
Penn State Extension. (n.d.). Interpreting irrigation water tests. https://extension.psu.edu/interpreting-irrigation-water-tests
PlantTalk Colorado. (n.d.). Houseplants: Watering (No. 1318). Colorado State University Extension. https://planttalk.colostate.edu/topics/houseplants/1318-houseplants-watering/
Pscheidt, J. W., & Ocamb, C. M. (Eds.). (n.d.). Fluorine toxicity in plants. Pacific Northwest Plant Disease Management Handbook. https://pnwhandbooks.org/plantdisease/pathogen-articles/nonpathogenic-phenomena/fluorine-toxicity-plants
Pscheidt, J. W., & Ocamb, C. M. (Eds.). (2026). Dracaena–Tip burn. Pacific Northwest Plant Disease Management Handbook. https://pnwhandbooks.org/plantdisease/host-disease/dracaena-tip-burn
Rowe, A. (2025). Effect of drainage layers on water retention of potting media in containers. PLOS ONE, 20(2), Article e0318716. https://doi.org/10.1371/journal.pone.0318716
Shaughnessy, D., & Pertuit, A. (n.d.). Indoor plants: Watering (HGIC factsheet). Clemson Cooperative Extension Home & Garden Information Center. https://hgic.clemson.edu/factsheet/indoor-plants-watering/
South, K. A., Thomas, P. A., van Iersel, M. W., Young, C., & Jones, M. L. (2017). Ice cube irrigation of potted Phalaenopsis orchids in bark media does not decrease display life. HortScience, 52(9), 1271–1277. https://doi.org/10.21273/HORTSCI12212-17
Spomer, L. A. (1976). Container soils are different. Ornamentals Northwest Newsletter, 1(8), 9–10. (Reprinted from Illinois State Florists’ Association Bulletin, No. 365, May–June 1976.) https://agsci.oregonstate.edu/sites/agscid7/files/horticulture/osu-nursery-greenhouse-and-christmas-trees/onn010809.pdf
Steil, A., & Rindels, S. (2024). How to select quality plant containers. Iowa State University Extension and Outreach, Yard and Garden. https://yardandgarden.extension.iastate.edu/how-to/how-select-quality-plant-containers
Trinklein, D. (2017). Caring for houseplants (G6510). University of Missouri Extension. https://extension.missouri.edu/publications/g6510
UConn Home & Garden Education Center. (n.d.). Houseplant watering recommendations. University of Connecticut. https://homegarden.cahnr.uconn.edu/factsheets/houseplant-watering-recommendations
UMass Extension Greenhouse Crops and Floriculture Program. (n.d.). Water quality for crop production. University of Massachusetts Amherst. https://www.umass.edu/agriculture-food-environment/greenhouse-floriculture/greenhouse-best-management-practices-bmp-manual/water-quality-for-crop-production
University of Illinois Extension. (n.d.). Watering. Houseplants. https://extension.illinois.edu/houseplants/watering
University of Maryland Extension. (n.d.). Overwatered indoor plants. https://extension.umd.edu/resource/overwatered-indoor-plants
University of Maryland Extension. (2023, March 10). Watering indoor plants. Home and Garden Information Center. https://extension.umd.edu/resource/watering-indoor-plants
University of Maryland Extension. (2026). Fungus gnats. https://extension.umd.edu/resource/fungus-gnats
U.S. Geological Survey Water Science School. (2018, June 12). Evapotranspiration and the water cycle. https://www.usgs.gov/special-topics/water-science-school/science/evapotranspiration-and-water-cycle