Introduction to Tillandsia – Andy Harrison


Tillandsia tenuifolia Blue Bud

(With thanks to Andy Harrison )


Tillandsias or “Air Plants” are an unusual group of plants, as they take in nutrients through their leaves and not their roots. As a result, they are epiphytic (growing on trees or cacti) or saxicolous (growing on rocks) and do not need soil to grow in (although a few species prefer to be potted rather than left hanging!)
They are plants of the ‘New World’, occurring from the south of the USA, through Mexico and Central America, and into South America. In the wild, they are found in a range of habitats from coastal desert, through forests and high up into more mountainous areas. They also an tolerate a range of temperatures, although they are not, as a rule, frost tolerant.
Air Plants are part of the Bromeliad (Bromeliaceae) Family and belong to the Genus Tillandsia. There are well over 500 species of Tillandsia that naturally occur, and a growing number of hybrids and cultivars which have been man made.

There are a number of features which seem to make the plants attractive to collectors:Firstly the plants themselves are quite variable in form.Many are relatively small and require little space. Not requiring soil, they can be mounted on wood, sea shells, rocks, in glass terraniums etc to form quite artistic and abstract pieces for display.They are relatively easy to maintain and can be neglected (within reason).The flowers form on an inflorescence which is often quite unique and colourful in its own right.

Tillandsias propagate through two methods:

As mentioned above, they do flower and it is the flowering that I certainly look forward to. The flowers do turn to seed. Some species self-pollinate whilst others are pollinated by hummingbirds, moths, butterflies, bees, and even bats. Growing tillandsias from seed is a long and patient process.Tillandsias also propagate by producing baby tillandsias (called pups), which develop on the plant after flowering. The pups will develop into new plants, genetically identical to the parent plant. Pups can be separated from the parent plant when they reach a manageable size, or left on the parent plant to form bigger clumps. The original parent plant will eventually die back after pupping.



Plant taxonomy is the field of science that deals with the description, identification, nomenclature and classification of plants. I mention this because there are rules and recommendations concerning the naming of plants, (refer to which will lead you to the so-called Melbourne code 2011). That said, the naming of Tillandsias is far from clear.

Classification of life forms is broken down into a hierarchical system devised by a Swedish scientist called Carl Linnaeus in the 18th Century. His classification starts with Kingdom (eg Plant Kingdom) and works down through Phylum, Class and Order and then Family (Tillandsias are part of the Bromeliad family), and then lastly Genus and Species.

Most animals and plants are formally known by the two names making up Genus and Species. For example, as modern people we are the only living representative of the genus Homo. We also have the specific name of sapiens to distinguish ourselves from our now extinct predecessors such as Homo neaderthalensis or Homo habilis. So we are known as Homo sapiens.

The plants we are interested in belong to the Genus Tillandsia. There are over 600 species of tillandsias. For example, there is Tillandsia ionantha, which has different characteristics from say, Tillandsia pruinosa. By the way, because we are talking about Tillandsias on this website, I have used the common practice of abbreviating the generic name, eg T. pruinosa.

It should be said here that the strict definition of a species implies that reproduction between members of different species can’t biologically happen. However this definition does not seem to strictly apply in biology and even less so in Tillandsias. When a new tillandsia plant is discovered and described, the arguments will follow as to whether this new plant is a new species, or a distinct variety of an existing species, or just part of natural variation of an existing species. And here’s the rub, not everyone will agree. So the naming of tillandsias can be confusing and I have several times bought differently named plants, only to find that they are actually the same beast!.

Worse still, some nurseries are not always strict with their naming conventions, so there are some tillandsias on the market that have incorrect names. So “caveat emptor” – let the buyer, beware.
It is my humble opinon that the ‘splitters’ seem to hold fort over the ‘lumpers’ and there are many Tillandsia species which may not deserve to be recognised as distinct species, but in fact are.


Tillandsia ionantha

There can be variations within a species which can be recognised, either formally or informally. These variations may come about as natural selection reacts to local differences in geography, climate, elevation etc. There are a number of varieties (often abbreviated to ‘var.’ or even ‘v.’) of T. ionantha, of which T. ionantha v vanhyningii and T. ionantha v stricta. Some variations are not formally named like T. disticha Minor and T. disticha Major.


Although not included in the two word Linnean name, the various tillandsia species can be grouped under one of 7 sub-genus’, which reflect some commonality. The distinctions are quite technical and I have decided to exclude them from the list hereunder. I do have these distinctions together with a list of species that fall under each sub-genus and would be more than happy to pass this one for anyone who’s interested. See the ‘Contact Me’ section of the website.

For interest’s sake, these sub-genus are:

Allardtia: Type species: T. guatemalensis.
This is the second largest group with almost 200 member species

 Anoplophytum: Type species: T Stricta
This is the third largest sub-species with almost 90 members

Diaphoranthema: Type species: T. recurvata.
This sub-species has 33 members, which are further divided into 6 groups named after a prominent member of each group.

Phytarrhiza: Type species: T duratii
This sub-genus comproses 34 species which are further split into 8 groupsn named as roman numerals from I to XIII.
Pseudalcantares: Type species: T. viridiflora
I can only find four species that make up this group.

Tillandsia: Type species: T. utriculata
This sub-species is the most numerous, nd contains at least 265 species, plus an additional 40 odd that have been transferred from the Vriesea genus.

Racinae (formerly Pseudocatopsis): Type species: T ropolocarpa
Only 2 members.

Evolution is a continuing process. There will be variations within a species due to natural differences in geography, climate, elevation etc.  resulting in plants of the same species having differing variations, which are not distinctive enough to warrant classification as a different species. For example, T. ionantha v vanhyningii and T. ionantha v stricta. Some variations are not formally named like T. disticha Minor and T. disticha Major.

Hybrids occur naturally (which to me, ought to imply that the parents were of the same species anyway) or can be induced artificially by using the pollen of one plant to fertilise the stigma of the other. Hybrids so derived, may be named using the following convention, eg. Tillandsia Silver Streak (T. funckiana X T.albida). Note the mixture of italics and normal type.


I’m no expert, but my understanding is that a Cultivar is a hybrid which is capable of sexual reproduction true to form, in other words, the sibling is like the parent hybrid. (Although I was planning to collect only naturally occurring species, I have acquired a few Cultivars through my initial ignorance!!).



Tillandsia punctulata


Remember though that this is largely based on my experience of growing Tillandsias in the Free State Province of South Africa, which is at altitude and has extremes of weather (see ‘About this Site’ elsewhere on this website)
Due to these extremes, I have battled to grow several Tillandsia species, noteably; T araujei, T gardneri, T geminiflora, T stricta, T arenicola and T. kirchoffiana. Others do not flower properly and I suspect my local temperatures are too extreme.


On the ‘Gallery’ page, I have uploaded photographs of some of my plants. With each photograph is some commentary about the plant and at the end of the commentary, the conditions under which I try to keep the plants. This is annotated, for example, as “CARE:  H; X: ?”. The first letter is about Light Conditions (High, Medium or Low). The second letter is about Watering (Xeric, Sub-mesic or Mesic). The third is for Humidity (High, Medium or Low). A question mark means that I don’t know!  Note that I have searched the Web for clues on how to care for the each Tillandsia species.




As a general rule, the darker green, softer leafed Tillandsias, (which also seem to be the ones that will benefit from being potted) tend to prefer shade rather than direct sunlight. The stiffer greyer leaved variety prefer bright light although that doesn’t necessarily mean full sun, and especially in the summer here.

I have read that Tillandsias can survive on light levels of 20 000 Lux, but will thrive at levels between 30 000 and 40 000 Lux. I wasn’t sure what that meant, so I bought a light meter. My first measurement were taken at 12h45 on 4th September on a bright clear cloudless early spring day and gave a reading of 100 000 Lux. By comparison, under shade netting in my veggie garden, I recorded 60 000 Lux, implying that my shade netting was 40%.

So I have used additional shade netting to try and get the following Light regimes.

40 000 Lux = High
30 000 Lux = Medium
20 000 Lux = Low.

Tillandsias take in nutrients through their leaves.They are frequently described as eiher Xeric (meaning they prefer dry conditions) or Mesic (wetter conditions) or an inbetween Sub-mesic.

In my local climate, I spray them in the mornings, on average every second or third day. I try not to use tap water, which is often heavily chlorinated, but use filtered (by reverse osmosis) water that the family uses for drinking. Fresh rain water is best of course, but the winters in Welkom are largely dry, and summer rainfall can be heavy and with hail, so natural soaking is a rare  event. Some specimens benefit by a long bath on occasions when the leaves of some species start to curl.

Some specimens are liable to rot, so ensure that the Tillies dry out during the day.

Some of the lower light Tillandsias, prefer a humid environment. As my home town is quite dry, especially in the colder winter months, I have added a few small pots of water attached to the frames which hopefully will make the local environment a bit moister. My plants are also in a veggie garden which gets watered daily, so the humidity levels will be slightly above the norm anyway.



Tillandsia funkiana

Tillandsias, being sub-tropical beasties, are quite comfortble in high temperatures, but, apart from Tillandsia usneioides, are not tolerant to cold temperatures, especially frost. In the summer, most of my tillandsias are mounted outside under shade cloth. Some of the potted tillies are kept in the greenhouse, and I use a combination of an extractor fan or an evaporative cooler, or fine mist sprays, to keep the temperature down below 30 degrees C. In the winter, I have them in a greenhouse with a heater if the temperature drops below 5 degrees C at night.


As a final comment, the Tillandsia that are truly epiphytic will be found in trees under some form of shade canopy. If your Tillandsias are recorded as found in wet tropical areas, then the level of shade will be higher than those described at altitude in dry forests, where light levels will by definition be higher. Tillandsias that are saxicolous and thus found on rocks and on cliff faces will presumably tolerate still  higher levels of light. However, some desert species for example, can still require good moisture as in their natural habitat may have coastal mists.


I’m not exactly a handiman, but I have constructed a series of frames made from 20mm x 20mm ‘par’ (planed all round) pine, which I have painted with some marine varnish to attempt some weather-proofing. The frame is around 0.9 m x 0.9 m (only because I could purchase the stuff in 1.8 m lengths), but it seems that anything larger would be a hassle man-handling. I reinforced the frame at the corners with some metal brackets. Attached to the frame, I have pinned (using fencing staples) some rigid plastic fence netting with a grid of about 32mm.

The frames themselves can be hung on something more permanent. I have some rectangular tubular bar mounted horizontally for the frames to hang on and inside my greenhouse, they are hung on horizontally mounted plastic drain pipes.

I hang the tillandsias on the plastic netting. The first lot of Tillandsias I had were individually mounted on off-cuts of old vine wood. They were fixed t the wood using a glue (such as “Fix All” – I have read that you shouldn’t use silicon glues for this). The glue is not ideal and as a back-up, I have tied them on with string. Around the top of the vine, I wrap a piece of wire with a hook, and use the hook to hang the mounted tillandsia on a wooden frame (see picture).

Some of my later tillandsias have been hung using the green plastic coated floral wire, and hung on the netting.

Be careful with wire, as I understand that copper wire is a no-no for tillandsias. The wire I use is galvanised steel binding wire.


With thanks to Andy Harrison from

DISCLAIMER – Whilst every effort has been made to ensure the information contained herein is factually correct, the author can take no responsibility for unexpected outcomes.