What is an air plant?

An air plant is one that lives off the ground, away from the soil. The scientific term is epiphyte (epi – above, over, on; phyte – plant), which really refers to plants that live on other plants.

Tillandsia ionantha

An air plant doesn’t and can’t live on air. It still needs sun, water and nutrients in the same way that plants living in the soil do. It obtains these from rain, minerals and organic matter that are part of its growing environment. In some situations these aren’t plentiful, so the plant will grow slowly.

If you buy an air plant hoping it will be maintenance free; it will, but only after it has died.

Many plants are epiphytes, they live on trees, rocks, telephone wires, fences, other plants and buildings; anything that doesn’t move too much.

When people say air plants they normally mean Tillandsia.

Air plants in the winter

January is a time of activity for my air plants, so I felt that it would be interesting to take some (rather badly lit) pictures of them.


This is the Tillandsia caput-medusae that flowered in the summer. You can see that the offset is growing quite strongly, and that the flower stalk remains. I am guessing by the green colouring that it is photosynthesising and thus paying its keep.


This is the T. brachycaulos that flowered and you can see that its offset is catching up in size with the parent plant. It is also more vigorous as you can see by its stronger green colour.


Some of the others are coming into bud – this is Tillandsia fuchsii var. gracilis and it seems to have produced this flower spike in the last 7 days.



This plant is the large T. fasciculata that was hanging from the pine tree in the garden during the summer, and I noticed that it had changed shape. Tillandsias seem to look just a bit lopsided before they come up to flower and show fresh growth in the middle of the plant. So I had a look in the centre:


and there is the beginning of the flower spike.

This plant:


T. seleriana was its companion on the pine tree, and is also a large plant (a double handful), and I suspect it is considering flowering, but I am not sure.


One of the first to flower last year, has finally produced an offset:


Though as you can see it took some finding.

And out of interest I thought it would be useful to compare the air plants to their bigger cousin Billbergia nutans, also a bromeliad, which flowers and produces offsets in the same manner, as you can see:



Finally, just a reminder about making sure that your air plants are dry after watering. I did manage to lose one, just after Christmas, to rot. If you are in doubt, hang them upside down to make sure that the water runs out from the leaf axils (where the leaves join the centre of the plant).


Tillandsia caput-medusae

This year I developed a ‘thing’ about air plants. It started with buying just one, meaning to attach it to an object to make a present for someone. Almost in the same way that you would stick on a sequin I guess. But of course, as soon as I actually touched it, I remembered that it was a life-form, not a bit of plastic.

So I got a couple more, and started trying to understand how they work. The easiest to observe in a short period of time (air plants live in slow time) is Tillandsia caput-medusae.


Tillandsia, named for Mr Tillandz (1640-1693) a Finnish botanist, by Linnaeus (many thanks Wikipedia) is a big genus, part of the Bromeliaceae family. They tend to originate in South and Central America, though not exclusively. Tillandsia caput-medusae invites comparison between the structure of the plant and the snake-hair of the Medusa’s head (lit. caput medusae). There are 4 specimens above, and you can see how they do (or don’t) fit the picture below. They tend to coil slightly more tightly when they are in need of watering.


Tillandsias are popularly known as air plants, which probably leads to the death of thousands in the home. The ‘air’ in air plant refers to their epiphytic nature: they live in air (on other plants, rocks, trees, phone wires, etc) rather than in soil. They don’t live on air, particularly not in centrally-heated domestic homes.


In the absence of roots, tillandsias absorb both water and nutrients through silvery trichomes on the surface of their leaves – seen in the above photo. These trichomes have three functions for the plant: their silvery colour reflects bright sunlight, they allow water to be absorbed from rain and atmospheric humidity, and they protect that water from evaporating once it has been captured. If you have an airplant, it is important that you bear this in mind when you are caring for it. It needs access to water regularly or it will die of dehydration, but it is in danger of rotting if the water is allowed to gather and rest in the spaces between the leaves.

Watering should therefore be done once or twice a week, depending on the conditions the plant is living it (sunny window in warm conditions – twice; no sun, chillier conditions – once). All it needs is to be run under the tap, or popped in a bowl of water for a bit. If your plant gets dehydrated leave it in a bowl of water overnight. As with all houseplants, it really helps to understand how your plant feels when it is healthy. You won’t damage it if you handle it regularly, as long as you are careful. A healthy plant will feel slightly cooler than ambient, and it will feel gently springy rather than crispy in your hand. This will vary between species of tillandsia, but for caput-medusae firm and gently springy is good.

Then drain it (on a teatowel or whatever comes to hand) for an hour or two, upside down so that the water can drain out from between the leaves. If your plant is growing upside down anyway, so much the better.

One of my caput-medusae caught me out by flowering long before I had expected it to. I am told that one way to encourage them to flower is to feed (weekly-weakly) with very dilute plant food, I use about 1/10th the recommended rate for my plants.  As you can see on the photo above the flower-stem comes from the centre of the plant in this case, and starts off green with pink tinges.


The inflorescence takes quite a while to develop, but once the purple flowers appear they last a very short time, slightly less than a day per flower with this plant. That said, the flowers are produced one at a time, so the display is quite long-lasting, and immensely attractive.


And once the flowers fade, the plant should move on to producing an offset  (a clone plant that remains attached to the parent until it is of sufficient size to live independently). You can just see the offset nestling in an older leaf at the bottom of the plant here.


Over time, the plants will produce a mass of many plants. Pictures of plants in the wild here, and here.

Update photos of offset: 8-10-16. (The wire is not for the purpose of restraint but suspension).