Famous last words heard by houseplants: “Bright indirect light?” This spot seems bright enough. Your interior light levels form the growth potential of the plant. Your care efforts realize that potential (watering, fertilizing, repotting). Good light is the PREREQUISITE for a plant to grow but the term “bright indirect light” fails to convey anything concrete. […]
I’ve created over a hundred plant time lapse videos and these articulating arms have made all the difference! Disclaimer: a portion of qualifying purchases made through these Amazon Affiliate links goes to support the work of House Plant Journal – bringing you clarity in houseplant care. Traditional tripods can’t fit into tight spaces but little […]
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“Bright indirect light?” This spot seems bright enough.
Your interior light levels form the growth potential of the plant. Your care efforts realize that potential (watering, fertilizing, repotting). Good light is the PREREQUISITE for a plant to grow but the term “bright indirect light” fails to convey anything concrete. At worse, it makes you think just any place the sun doesn’t shine is considered indirect light. And our eyes adjust to a wide range of light levels so you will NOT feel the difference. Instead, those with huge, unobstructed windows and/or skylights are patting themselves on the back at how good they are with houseplants while those with smaller windows living between buildings are struggling to figure out why their fiddle leaf fig always ends up with 90% of their foliage lost.
Disclaimer: this article contains Amazon Affiliate links. Earnings from qualifying sales goes to support the work of House Plant Journal – thank you!
Step 1: Get a light meter and get to know how bright your indirect light actually is. Here are a few that I think work well:
This is the Dr. Meter LX1330B Light Meter that I’ve been using – pricing has been varying wildly on Amazon but it should be around $40-60.
What about apps? Android devices do not have standardized ambient light sensor hardware and the iOS platform doesn’t give access to the iPhone light sensor, which means those apps are doing a rough calculation based on the camera brightness value. An app might be able to give you a rough idea, but a dedicated device will do the proper cosine correction for the angle of incident light (that’s what the white dome is for).
Step 2: Bookmark this page so you can look up the levels of indirect light necessary for various plants. I don’t have every possible houseplant but after reading a few of these, I think you’ll get the idea.
Commercial Light Levels: most of our typical “houseplants” are grown in greenhouses with varying layers of shade cloth. To give you a rough idea, “50% Shade” would measure to 5000 foot-candles (FC) and “90% Shade” comes to 1000 FC – this is the strength of the sun shining through different layers of shade cloth, which is a black net-like material. These numbers are easily searchable on the internet – I’ve included the source links where applicable. ***Don’t expect to achieve these light levels indoors from your indirect light.***
Interior Light Levels: plants can technically survive in a wide range of light levels so do not take the numbers listed here as prescriptive – they aren’t strict requirements. You should think of them as guidelines for good growth. Another consideration is that “good growth” is subjective as any plant will take the shape of its light situation – up to a certain point, it’s not entirely under your control! These numbers are gathered from my own observations and measurements. ***Use these as guidelines.***
How to measure: from the spot where your plant is sitting, while the sun is NOT in view, you want the measurement to be above the “good growth” foot-candle reading. Measure at different times of the day and in different weather conditions so you can get a sense for the average intensity of your indirect light. When the sun IS in view, you want the duration to be less than what is stated as tolerable – and if the sun will be in view for longer, then block it with a white sheer curtain.
If you appreciate a sensible and logical approach to houseplant care, I think you’ll enjoy my book, The New Plant Parent, which covers all the fundamentals of houseplant care:
African Violets
Commercial Light Levels: 1000-1200 FC
Interior Light Levels: 200 FC for minimal growth; good growth above 400 FC; 2-3 hours direct sun tolerable
Source: https://mrec.ifas.ufl.edu/foliage/folnotes/africanv.htm
Aglaonema (Chinese Evergreen, and several species)
Commercial Light Levels: 1000-2400 FC
Interior Light Levels: 100 FC for minimal growth; good growth above 200 FC; 1-2 hours direct sun tolerable
Comments: Classical “low light” tolerant houseplant. Plant dies slowly below 100 FC and will look ugly after a year or two.
Source: https://mrec.ifas.ufl.edu/Foliage/folnotes/aglaonem.htm
Air Plants (Tillandsia – many species)
Commercial Light Levels: 3000-7000 FC
Interior Light Levels: 200 FC for minimal growth; good growth above 400 FC; 3-4 hours direct sun tolerable
Comments: my air plant care video here https://youtu.be/sjNVLgEbvOY
Source: https://bromeliadsocietyhouston.org/genera-intro/tillandsia/
Alocasia (several species)
Commercial Light Levels: 2000-5000 FC (estimated based on ‘part shade/part sun’)
Interior Light Levels: 200 FC for minimal growth; good growth above 400 FC; 3-4 hours direct sun tolerable
Comments: Leaves will very likely die back. Calmly repot the base into fresh soil and new leaves may sprout.
Source: https://edis.ifas.ufl.edu/fp033
Anthurium (several species)
Commercial Light Levels: 1500-2000 FC
Interior Light Levels: good growth above 400 FC; 1-2 hours direct sun tolerable
Source: https://mrec.ifas.ufl.edu/Foliage/folnotes/anthuriu.htm
Aspidistra (Cast-Iron Plant)
Commercial Light Levels: 2000-5000 FC
Interior Light Levels: 100 FC for minimal growth; good growth above 200 FC; 1-2 hours direct sun tolerable
Comments: Classical “low light” tolerant houseplant. Plant dies slowly below 100 FC but will look fine for many months, possibly years.
Source: https://ufdcimages.uflib.ufl.edu/UF/00/08/93/74/00001/EP14700.pdf
Areca Palm
Commercial Light Levels: 5000-6000 FC
Interior Light Levels: 200 FC for minimal growth; good growth above 400 FC; 3-4 hours direct sun tolerable
Source: https://mrec.ifas.ufl.edu/Foliage/folnotes/areca.htm
Arrowhead Vine (Syngonium podophyllum)
Commercial Light Levels: 1500-3000 FC
Interior Light Levels: 100 FC for minimal growth; good growth above 200 FC; 2-3 hours direct sun is tolerable.
Source: https://mrec.ifas.ufl.edu/Foliage/folnotes/nephthyt.htm
Begonia (several species)
Commercial Light Levels: 2000-2500 FC
Interior Light Levels: 200 FC for minimal growth; good growth above 400 FC; 1-2 hours direct sun tolerable
Source: https://mrec.ifas.ufl.edu/foliage/folnotes/begonias.htm
Bird-Of-Paradise (Strelitzia)
Commercial Light Levels: 2000-5000 FC (estimated based on ‘part shade/part sun’)
Interior Light Levels: 400 FC for minimal growth; good growth above 800 FC; 4-5 hours direct sun tolerable
Source: http://hort.ufl.edu/database/documents/pdf/shrub_fact_sheets/strrega.pdf
Calathea (several species)
Commercial Light Levels: 1000-2000 FC
Interior Light Levels: 200 FC for minimal growth; good growth above 400 FC; 1-2 hours direct sun tolerable
Source: https://mrec.ifas.ufl.edu/Foliage/folnotes/calathea.htm
Cordyline (Ti Plant)
Commercial Light Levels: 3000 FC
Interior Light Levels: 200 FC for minimal growth; good growth above 400 FC; 3-4 hours direct sun tolerable
Source: https://mrec.ifas.ufl.edu/Foliage/folnotes/cordylin.htm
Croton (several species)
Commercial Light Levels: 3000-5000 FC
Interior Light Levels: 400 FC for minimal growth; good growth above 800 FC; 4-5 hours direct sun tolerable
Source: https://mrec.ifas.ufl.edu/Foliage/folnotes/crotons.htm
Dieffenbachia (Dumb cane; several species)
Commercial Light Levels: 1500-3000 FC
Interior Light Levels: 100 FC for minimal growth; good growth above 400 FC; 1-2 hours direct sun tolerable
Source: https://mrec.ifas.ufl.edu/Foliage/folnotes/dieffenb.htm
Dracaena (several species)
Commercial Light Levels: 2000-3000 FC
Interior Light Levels: 100 FC for minimal growth; good growth above 200 FC; 3-4 hours direct sun tolerable
Comments: Very low-light tolerant – I’ve seen one last for years at 30-50 FC. It had very long, thin and dark green spindly foliage but it was alive.
Source: https://mrec.ifas.ufl.edu/Foliage/folnotes/dracaena.htm
English Ivy (Hedera helix)
Commercial Light Levels: 1500-2500 FC
Interior Light Levels: 200 FC for minimal growth; good growth above 400 FC; 2-3 hours direct sun tolerable
Comments: lower leaves will drop off – generally doesn’t look nice after a year.
Source: https://mrec.ifas.ufl.edu/Foliage/folnotes/english.htm
Hoya (several species)
Commercial Light Levels: 1500-2000 FC
Interior Light Levels: 100 FC for minimal growth; good growth above 200 FC; 3-4 hours direct sun tolerable
Source: https://mrec.ifas.ufl.edu/Foliage/folnotes/waxplant.htm
Ferns (Boston Fern, Bird’s Nest Fern, Maidenhair Fern)
Commercial Light Levels: 1500-3000 FC
Interior Light Levels: 100 FC for minimal growth; good growth above 200 FC; Boston fern – 3-4 hours direct sun tolerable; Bird’s nest fern/maidenhair fern – 1-2 hours direct sun tolerable but must keep soil evenly moist
Comments: my Maidenhair fern care video here: https://youtu.be/Q1FecMy2zXE
Source: https://mrec.ifas.ufl.edu/Foliage/folnotes/bostonF.htm https://mrec.ifas.ufl.edu/Foliage/folnotes/birdnest.htm
Ficus (Rubber plant, elastica; Fiddle leaf fig, lyrata; benjamina)
Commercial Light Levels: 2000-6000 FC
Interior Light Levels: 400 FC for minimal growth; good growth above 800 FC; 3-4 hours of direct sun tolerable
Comments: if you don’t have at least 400 FC of indirect light, your fiddle leaf fig will lose most of its lower leaves. If you have small windows, save your money.
Source: https://mrec.ifas.ufl.edu/Foliage/folnotes/ficus.htm
Fittonia (Nerve Plant)
Commercial Light Levels: 1500-2500 FC
Interior Light Levels: 100 FC for minimal growth; good growth above 200 FC; avoid direct sun
Source: https://mrec.ifas.ufl.edu/Foliage/folnotes/fittonia.htm
Maranta (Prayer Plant)
Commercial Light Levels: 1000-2500 FC
Interior Light Levels: 100 FC for minimal growth; good growth above 200 FC; 2-3 hours direct sun is tolerable.
Source: https://mrec.ifas.ufl.edu/Foliage/folnotes/maranta.htm
Monstera deliciosa
Commercial Light Levels: 1000-2500 FC (estimated based on ‘shade/filtered sun’)
Interior Light Levels: 100 FC for minimal growth; good growth above 400 FC; 2-3 hours direct sun is tolerable.
Comments: my detailed monstera care article – https://www.houseplantjournal.com/home/2017/1/25/monstera-deliciosa-house-plant-journal
Source: https://edis.ifas.ufl.edu/pdffiles/HS/HS31100.pdf
Norfolk Island Pine
Commercial Light Levels: 5000-6000 FC
Interior Light Levels: 200 FC for minimal growth; good growth above 400 FC; 2-3 hours direct sun is tolerable.
Source: https://mrec.ifas.ufl.edu/Foliage/folnotes/norfolk.htm
Parlour Palm (Chamaedorea)
Commercial Light Levels: 1500-3000 FC
Interior Light Levels: 100 FC for minimal growth; good growth above 400 FC; 1-2 hours direct sun tolerable
Source: https://mrec.ifas.ufl.edu/Foliage/folnotes/chamaed.htm
Peace Lily (Spathiphyllum)
Commercial Light Levels: 1500-2500 FC
Interior Light Levels: 100 FC for minimal growth; good growth above 200 FC; 1-2 hours direct sun is tolerable.
Comments: Very “low light” tolerant – down to 50 FC, but will just barely survive and have high risk of root rot. Overall plant will gradually lose leaves and become thinner in low light. My peace lily care video – https://youtu.be/GpIsAhmWDbQ
Source: https://mrec.ifas.ufl.edu/Foliage/folnotes/spathiph.htm
Peperomia (many species)
Commercial Light Levels: 1500-3500 FC
Interior Light Levels: 100 FC for minimal growth; good growth above 200 FC; 2-3 hours direct sun is tolerable.
Source: https://mrec.ifas.ufl.edu/Foliage/folnotes/pep.htm
Phalaenopsis (Moth Orchid)
Commercial Light Levels: 1000-1500 FC
Interior Light Levels: 200 FC for minimal growth; good growth above 400 FC; 2-3 hours direct sun is tolerable.
Source: http://www.aos.org/AOS/media/Content-Images/PDFs/GrowingtheBestPhalsPart_3.pdf
Philodendron Vines (Heart-leaf, Brasil, etc)
Commercial Light Levels: 1500-3000 FC
Interior Light Levels: 100 FC for minimal growth; good growth above 200 FC; 2-3 hours direct sun is tolerable but leaves may lose color.
Comments: Very “low light” tolerant – down to 50 FC, but will just barely survive.
Source: https://mrec.ifas.ufl.edu/Foliage/folnotes/philo-hl.htm
Philodendrons (Moonlight, Imperial Red, Prince of Orange, Pink Princess, etc.)
Commercial Light Levels: 1500-2500 FC
Interior Light Levels: 200 FC for minimal growth; good growth above 400 FC; 2-3 hours direct sun is tolerable.
Source: https://mrec.ifas.ufl.edu/Foliage/folnotes/philo-sh.htm
Pilea (Aluminum plant, cadierei and others; NOTE: Pilea peperomioides not specifically mentioned)
Commercial Light Levels: 1000-2000 FC
Interior Light Levels: 200 FC for minimal growth; good growth above 400 FC; 2-3 hours direct sun is tolerable.
Source: https://mrec.ifas.ufl.edu/Foliage/folnotes/pilea.htm
Polka Dot Plant (Hypoestes)
Commercial Light Levels: 3000-3500 FC
Interior Light Levels: 200 FC for minimal growth; good growth above 400 FC; 2-3 hours direct sun is tolerable.
Comments: should be cut back every few months to keep bushy, otherwise will grow leggy.
Source: https://gpnmag.com/article/culture-report-hypoestes-hippo-series/
Pothos (Epipremnum aureum, Scindapsus pictus)
Commercial Light Levels: 3000-5000 FC
Interior Light Levels: 100 FC for minimal growth; good growth above 200 FC; 3-4 hours direct sun is tolerable.
Comments: Very “low light” tolerant – down to 50 FC, but will just barely survive.
Source: https://mrec.ifas.ufl.edu/Foliage/folnotes/pothos.htm
Sansevieria (Snake Plant, Mother-in-law’s Tongue)
Commercial Light Levels: 1000-6000 FC
Interior Light Levels: 100 FC for minimal growth; good growth above 200 FC; 5-6 hours direct sun is tolerable.
Comments: Very “low light” tolerant – down to 50 FC, but will just barely survive and be at high risk of root rot. New leaves grown at low light levels will be long, thin and floppy.
Source: https://mrec.ifas.ufl.edu/Foliage/folnotes/sansevie.htm
Schefflera (Mini Umbrella Tree, Schefflera arboricola; Umbrella Tree, Brassaia actinophylla)
Commercial Light Levels: 5000-7000 FC
Interior Light Levels: 100 FC for minimal growth; good growth above 200 FC; 2-3 hours direct sun is tolerable.
Source: https://mrec.ifas.ufl.edu/Foliage/folnotes/scheffle.htm
Schlumbergera/Rhipsalidopsis (Christmas/Thanksgiving/Easter Cactus)
Commercial Light Levels: 1500-3000 FC
Interior Light Levels: 200 FC for minimal growth; good growth above 400 FC; 3-4 hours direct sun is tolerable.
Source: https://www.plantgrower.org/uploads/6/5/5/4/65545169/holiday_cactus_production_guide.pdf
Spider Plant (Chlorophytum)
Commercial Light Levels: 1000-2500 FC
Interior Light Levels: 200 FC for minimal growth; good growth above 400 FC; 2-3 hours direct sun is tolerable.
Source: https://mrec.ifas.ufl.edu/Foliage/folnotes/spider.htm
Staghorn Fern (Platycerium)
Commercial Light Levels: 1000-2000 FC
Interior Light Levels: 200 FC for minimal growth; good growth above 400 FC; 3-4 hours direct sun tolerable
Comments: my staghorn fern care video here: https://youtu.be/bTM3WLwfq78
Source: http://edis.ifas.ufl.edu/mg015
Succulents (Aloe, Echeveria, Euphorbia, etc.)
Commercial Light Levels: 5000 FC
Interior Light Levels: 400 FC for minimal growth; good growth above 800 FC; 2-3 hours direct sun is preferred; 5-6 hours tolerable.
Comments: Aloe and Euphorbia can stay looking mostly the same down to 200 FC; Echeveria will stretch when grown indoors after several months – it’s inevitable. You can propagate by taking leaf cuttings and stem tip cutting – they simply do not stay compact and cute forever. Here’s a video on succulent leaf propagation: https://youtu.be/laAtQf8kwEA
Source: https://hort.ifas.ufl.edu/floriculture/pdfs/crop_production/Cacti%20and%20Succulents_ENHFL04-006.pdf
Yucca
Commercial Light Levels: 6000-7000 FC
Interior Light Levels: 400 FC for minimal growth; good growth above 800 FC; 3-4 hours direct sun is tolerable.
Comments: often confused with Dracaena fragrans (Corn Plant), which is far more low-light tolerant. Yucca will not perform well below 400 FC.
Source: https://mrec.ifas.ufl.edu/Foliage/folnotes/yucca.htm
ZZ Plant (Zamioculcas zamiifolia)
Commercial Light Levels: 1000-2000 FC
Interior Light Levels: 100 FC for minimal growth; good growth above 200 FC; 3-4 hours direct sun is tolerable.
Comments: often classified low-light tolerant, ZZ plant will survive with 50 FC but will be at high risk of root rot.
Source: https://edis.ifas.ufl.edu/ep252
