A Cautionary Post

Rust an Air Plant Toxin

A heads up on air plant toxins

You’ve probably heard the worn-out excuse: my dog ate my homework. But, what about: my cat ate my air plant? Find out if air plants are toxic, and learn about things that are toxic to air plants.  Although these toxins are common, thankfully, they are avoidable.Wow - This post will show you what metals are toxic to air plants

This post may contain affiliate links, and I love all the products I promote.

My Cat Ate My Air Plant

First off, thankfully, no, air plants are not toxic to humans or pets. So if your cat, or dog, or child, eats your air plant it will be no worse for wear.

It is far more likely that toxins may be introduced to your air plant. Here’s what the toxins are and how to avoid them.


As harmless and pretty as copper appears, it is toxic to air plants and should be avoided. Don’t use copper wire, copper plant holders or pressure-treated lumber, as the chemicals to treat the wood contain copper.

Copper Air Plant Toxin

Too bad, so sad! This copper terrarium won’t be housing any air plants.

Boron, Zinc, and Urea-Nitrogen

Before using a particular fertilizer read the Guaranteed Analysis to see if boron, zinc or urea-nitrogen are included, as these elements are harmful to air plants.

While you want a fertilizer without boron, zinc or copper, air plants do need nitrogen. They just need it in a usable form. Look for non-urea nitrogen fertilizer. Fertilizers containing urea depend on bacteria in soil to convert the nitrogen into a usable form for the plants. As air plants are not rooted in soil they cannot absorb nitrogen in this form. Instead, the air plant will be harmed instead of helped.

Tip: To be on the safe side, use a fertilizer specifically formulated for tillandsias or bromeliads.

To learn more about fertilizing air plants, check out the post below.

Fertilize for Faster Growth and More Vibrant Blooms

Start Feeding Your Air Plants



When creating displays be advised that rust is toxic to tillandsia.

Rust is toxic to air plants

If using rusted metals, such as the industrial-style object in the background of this photo, make sure the air plants and the rust are far enough away that they don’t touch.

Now that you know which materials and fertilizers to avoid when caring for and displaying your air plants, you can avoid unnecessary air plant fatalities 🙂

  1. Barbara says:

    Thanks for the wonderful information I have my air plants in a seashell and on a amethyst stone so far they are doing great.

    1. Anna says:

      I’m so glad to hear it! Thanks for sharing!

  2. Mary says:

    Is it true that tap water needs to sit for four hours to allow the chlorine to evaporate before dunking my air plants?

    1. Anna says:

      Allowing the chlorine to evaporate before using is always a good idea. That said, honestly, I haven’t been taking that precaution and my air plants look great. Letting the water sit just became too much of a hassle. If your water is heavily chlorinated, it may be worth the trouble of letting the water sit.

  3. Candy says:

    I have led lights I use for my orchids and anthuriums.. will air plants benefit from this … or not? I live in a dry climate { Tucson} and I keep my orchids and anthurium on stones with water …. what do you recommend Thanks

    1. Anna says:

      The added humidity will definitely benefit your air plants. I too live in an arid climate (and grow orchids – they just seem to go together). I use a humidifier set to low and it does wonders for my air plants.

  4. Lara says:

    Thanks so much for your beautiful blog! I want to make a hanger out of embroidery hoops & prefer to stain or paint them to match my home decor. Would house paint or polyurethane hurt the plants?

    1. Anna says:

      Sounds beautiful!!! Your air plants will be fine.

  5. Claire R Groom says:

    Thank you for the posts. I’ve learned a lot. I live in a relatively high-humidity area and couldn’t figure out why some of my air plants were drying out.. I therefore spray misted more frequently to no avail. I’m soaking them now and realized they werent getting enough water. Thank you and hope they will get more “hydrated”.
    Also didn’t know they needed fertilizer! Thank you for all the information.

    1. Anna says:

      Soaking air plants really helps to hydrate them – I just want to emphasize the need to dry them thoroughly up-side-down after watering. Crown rot is real and can be prevented by letting them dry out after watering.

      Also, about fertilizing – use it sparingly.
      All my very best,

  6. Tisa says:

    So glad to find you Anna.
    I love air plants and do my best to care for them. I have cats and one of them likes to eat the plants. So I have them in glass hanging globes. Even still I am not too successful with them. They have their weekly bath, & dry overnight before returning to their homes. I have lost many of them. Do you think it’s because of being contained in the the glass globe? I use tap water, but didn’t realize I should let it sit 24 hours before putting them in it. Maybe that’s what kills them. I have fertilized them to in the past. I would appreciate any suggestions. It’s always so sad when they die.
    Thank you so much for any help.

    1. Anna says:

      I’m so glad you found me too!
      My guess would be the glass globes. It sounds like you’ve got watering and, just as importantly, drying down. Air plants do best with good air circulation. Also, make sure the air plants are out of direct sunlight.
      I’d love to hear how it goes!

  7. Amy B. says:

    I wanted to make a planter out of an old dinosaur toy but would like to spray pain in first. Can you tell me if the paint would be harmful to my air plants? Also questioning the safety of my crochet mercerized cotton and twine. Thank you for any advice.

    1. Anna says:

      While air plants are sensitive to some toxins (as you have read), I would make sure the paint is completely dry and then see how it goes. Also, mercerized cotton and twine will be fine. If you’ve got a minute, send me a picture of your air plant creation. My curiosity is piqued! [email protected]

  8. Suzette says:

    my daughter has seen so many pictures on Pinterest showing airplants in Copper ‘plumbing’ elbow fittings and wanted to do this – guess it isn’t a great idea then?

    1. Anna says:

      As copper is toxic to air plants, copper tubing isn’t the best option for the long-term health of air plants, but if you just want to create a beautiful air plant arrangement and are willing to replace the air plants as needed, then use copper tubing. The plants will last for quite a while, as it will take time for the toxicity to become fatal. It won’t happen overnight.


  9. Shaun says:

    I have a few air plants that were in copper holders for about a month or so. After reading this article I’ve relocated them. They look totally fine at the moment but I’m curious to know if they have been condemned.

    1. Anna says:

      Honestly, I am not sure if they absorbed enough toxins to cause harm. But, by moving them they will have a better chance of living longer and healthier. I am going to be optimistic and say that no, your air plants are not condemned.
      Take care,

  10. Shannon says:

    I have Read over your recommendations, however, I make Wall decor using different item that will hold my airplants. I have Intentionally given my galvanized little buckets a rustic look, by making them rusted. All my air plants have been doing very well. Is is possible that it’s a fluke they haven’t died or that they will eventually die?
    Thank you!

    1. Anna says:

      Interesting, thanks for sharing. How long have you been caring your air plants in this way – in rusted containers? I would love to know how they fare. Air plants usually die very slowly – cold damage is an exception. (They show signs of cold damage very quickly.) I’d love for you to keep me in the loop.

  11. Rebecca says:

    What about wood, driftwood, forest deadwood etc. Would these be toxic to airplants?

    1. Anna says:

      Driftwood and forest deadwood should be fine as long as you don’t use walnut as it contains chemicals that inhibit the growth of other plants. Avoid decomposing/rotting wood.

      Also, if you can place the air plants on the wood without gluing them to the wood, your air plants will live much longer.

      Happy air planting,

  12. Pepito Paguirigan says:

    I noticed that most available plant hanger in the market is galvanized wire and I’ve been using galvanized wire to hang my plants. Is this a bad idea?

    1. Anna says:

      Thank you for your question. Galvanized wire is a good choice for air plants as it prevents the wire from rusting – and rust is toxic to air plants. So, keep using your galvanized wire.
      All the best,

  13. Katarina says:

    Hi Anna
    First, thank you for all the great advice and tips.
    I recently moved to Florida and discovered air plants…now I’m addicted. I’ve ordered several buds for my home after being told the beautiful ones i originally purchased would never flower again…something the florist assumed I knew. Now I’m trying to find out how long it takes for a bud to grow to maturity and bloom, and then how long before it will produce buds of it’s own.

    1. Anna says:

      It is hard to give these things a timeline – some buds grow more quickly than others. The flowers on air plants can be spectacular – or kind of meh – depending on the type of air plant. I especially like the flowers from these air plants: T. aeranthos, T.melanocrator v. concolor, T. stricta, T. fasciculata and T. caput-medusae.
      As captivating as the flowers can be, enjoying the air plants as much as the flowers can bring a lot of satisfaction.

      About coming to maturity. That is also a tricky question – some air plants bloom young and small – while others grow for several years before blooming. Keeping that in mind, here are a few factors that can contribute to blooming:
      Fertilizer – can help produce colorful blooms, but use judiciously to prevent burning your air plants.
      Sunlight – it takes a lot of energy to produce flowers.

      Also, an unhealthy air plant can produce flowers at a last attempt for self-preservation.

      Wishing you lots of blooming air plants,

  14. Gayle Fiford says:

    Hi Anna.
    Thanks for interesting info very interesting. My air plants grow outside on a metal plant holder which does not get a lot of sun but light. Problem does not flower?

  15. Fred Chang says:

    Thanks for post! I just had plants wither in silver (or silver plate ) bowl and also a brass scale. The silver was worse than the brass.

    1. Anna says:

      Good to know! Thanks so much for sharing! Do you have others on a porcelain or something similar to compare the air plants reaction?
      I appreciate your information.
      Have a great day,

  16. Maria Buchanan says:

    I’m very new to air plants and have learned a lot from this site. I was told to use glue to attach them to their container. Is regular hot glue ok to use? Is aluminum ok to use as containers? Thank you in advance!

    1. Anna says:

      You can use hot glue or you can also use floral adhesive.


      Yes, I do believe that aluminum should be okay for your air plants.
      It sounds like you’re creating something wonderful!

  17. Marylee says:

    Can i use the rain water afer a week of sitting outside in a bucket

    1. Anna says:

      Yes. Rain water is fine and can be reused over and over. Just for the record, your tap water is probably just fine. I have used tap water, rain water, and pond water and mine are all thriving. I have A LOT of air plants, so in the summer I fill a kiddie pool outside and let the water warm up for a day, and then soak my air plants the next day. In the winter months I fill my bathtub with tepid water and soak them in there.
      Thank your for your thoughtful question.

    2. Roland Pacubas says:

      Can I use driftwood from the beach, will the salt in the wood affect the plant.

      1. Anna says:

        Ooooh! Thanks for your thoughtful question! Yes, as-is, the salted driftwood would likely harm your air plants. To use the driftwood, soak it in water for a couple of weeks, changing the water every day. Rotate the driftwood periodically to submerge different parts of the driftwood.

  18. Rachael says:

    Hi, I’m planning on using this a spice rack made of chrome plated heavy gauge stainless steel wire to house my large collection of air plants. Will stainless steel and chrome be be fine for the air plant? Just want to make sure they aren’t toxic to them.

    1. Anna says:

      Yes chrome and stainless steel are not toxic to air plants. Sounds like a beautiful, creative way to display air plants. I’d love to see a picture. You can email me at: [email protected]

  19. Rebecca Ogden says:

    Some really great information! My friend wants me to make her one of those wire air plant holders that is attached to a quartz stone (l do wire-working). My question is: Is aluminium toxic to the plants? I have aluminum wire and silver-plated copper wire. I would feel better using the aluminum if it’s safe.
    Thank you!

    1. Anna says:

      Aluminum should be fine. I’d love to see a picture of the air plant holder!! You can email me at [email protected]
      Thank you for your thoughtful question,

  20. Katie says:

    What about using fish tank water? I had heard it was a good option to use the water from cleaning a fish tank, but I have no idea what’s in it with regard to nitrogen and urea and whatnot.

    1. Anna says:

      Good question. I haven’t ever used fish tank water–though my kids have several tanks…

      I think it would depend on how often you change the water. If you keep your tanks pretty clean the salts would be lower. Also, you could dilute the fish tank water with tap water. I would check the pH before I tried it. Air plants prefer a pH between 5.5 and 6.0. Keep in mind that air plants take a long time to show signs of stress. So, if you do try the experiment, use the same air plants with the fish water.

      Another thing to consider is that because air plants are epiphitic they are unable to convert urea-based nitrogen fertilizer into a usable form.

      If you try the experiment, let me know how it goes.
      Thanks for your question,

  21. Claudio Badin says:

    Buon giorno sono Claudio chiedo un suggerimento 2 anni fa ho comperato una delle vostre bellissime piante,dopo 2 mesi ha fatto un bellissimo fiore blu, dopo ltre mesi ha messo tre figli,chiedo come posso separarli dalla pianta madre senza romperla ? ringrazio della risposta e saluto cordialmente Claudio.

    1. Anna says:

      Congratulations on your air plant babies! To separate the plantlets from the mother plant, grasp the two plants by the base and pull them apart with your fingers.

  22. Ona Stanley says:

    I’d like to be sure as to how I fertilize my airplants. Your article says once a month,
    after watering. Should I wait until the plant is completely dry before apply the fertilizer? I use a spray fertilizer specially formulated for airplants.

    1. Anna says:

      Good question. After watering, you can fertilize your air plants while they are still wet.

  23. Linda says:

    That’s weird, I just read something the other day that said copper was beneficial to air plants. So much conflicting information on the internet

    1. Anna says:

      I think copper is pretty and I see copper air plant containers all over the internet, but I do recommend keeping your air plants away from it. Or, put it to the test and let us know your findings. Keep in mind that it is a slow decline.

  24. Kelly says:

    I was going to put my new arrivals in my copper stainer…..glad I got this tip today! Thanks so much, you just saved the plants I dont even have yet!

    1. Anna says:

      I’m glad you read this post BEFORE you bought your air plants! I hope you get your air plants soon. Here’s a link to a few of my favorites:
      T Harrisii
      T. Xerographica
      T. Velutina
      T. Caput-medusae
      Enjoy your air plants!

  25. Mose says:

    You could always try a nice thick layer or two of clear coat spray paint… I really like Rust-Oleums Triple-thick Glaze. It seems to be safe enough for my tillandsias, especially if the copper pieces aren’t outside in the elements all the time. Just keep an eye on the metal, making sure it’s covered nicely and applying more coats as it wears off with time.

    1. Anna says:

      That’s great advice!

  26. Lisa Faulkner says:

    So what if you coat the copper with several layers of a spray polyurethane, really really well? Would that make a barrier so the copper could still be used? Could this be used on iron (that might rust), they make marine poly!

    1. Anna says:

      Hi Lisa,
      Spraying copper with polyurethane to serve as a protective barrier between air plants and copper (or iron) is definitely worth a try. I am all about experimentation.

  27. Mr. Moosling says:

    How about brass?

    1. Anna says:

      Great question Mr. Moosling! As brass is an alloy of copper and zinc (both of which are toxic to air plants), I would avoid using it. -Anna

    2. Anna says:

      Mr. Moosling,
      I am going to revise my previous position. My brother (who studied chemistry) thinks that although both copper and zinc are toxic to air plants, perhaps, when they are combined to produce brass (an alloy of copper and zinc) they are less reactive. So, I would go ahead and try using brass as an air plant holder and see what happens. If you’d rather not experiment, stick with stainless steal.
      Good Luck!

  28. Michelle sexton says:

    Thank you for this post! I’ve had some air plants that have had a difficult time since I moved them to a copper plant holder. This explains why the tips have been dying.

    1. Anna says:

      Yes, it’s a slow death, but copper is toxic to air plants.

  29. Chantile says:

    This is sooo good to know! I have some super cute copper pieces, but I will find something even better now! Thanks! 🙂

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