People are idiots. But, I wander off topic. I think it is because most of the time they are talking about growing the plant in totally different conditions then nature. Spaths are used in those "betta bowls" so we know they will grow in water.
It is ASSUMED by a lot of people that water = rot so they assume you can't water plants too much. And most people don't understand what a rain forest is. Like you said, the plants are drenched for months and then they are dry for months, though that being said, rainforests also differ in amounts of rainfall, in the Pacific NW it's more like a constant dribble while in Belize it's a flood, a drought, a flood, a drought, etc. And some plants are dormant during the dry season, noone really wants a dormant houseplant.
As far as light, well, most of the plants are not growing at the tops of the canopies, so while a lot of them are growing taller to get more light they don't grow tall enough to get full sun. And a lot of understory trees need the shade. While other trees need shade when young but then become the top of the canopy as they age.
Most growers are growing plants for the middle of the country and give rather generic instructions.
As for the plants you list, I keep my philodendrums in moderte shade, I've found the leaves burn otherwise, but a few of the philos like full sun and will grow towards it. I just look at the plant, is it growing toward the light? Leaves too small? Like the philo on my desk, it's going home as it's just not bright enough here for it. So I move them to more or less light depending on what they are doing. Monstera, zygocactus, pothos all burn here in full sun. Though the pothos will get huge and grow in full sun it seems to prefer light to heavy shade. Same with the monstera.
Then you have to think about humidity. Rain forests are HUMID, year round, even during the dry spells. Most people can't replicate that at home. We rarely have humidity less than 80%, so I tend to stick with tropicals as they usually won't rot here.
Hope this helps, it's just my perspective on the matter.
The main point is, I think, that these plants are being grown out of their comfort zone, a lot of time not much is known about the cultivation so everyone just falls back on generic care instructions.
Good luck with your article.
Tally HO!

I live in Galveston, a semi-tropical island off the coast of Texas.

Good observations. Just curious, what type of soil do you use? Off the shelf? Or do you mix it?

You are absolutely correct about variations in rain fall in the forests of the world. Dr. Croat and I have talked many times about how some rain forests are soaked and are actually known as wet forests while others are known by other designations which indicate how wet or less wet they are. Some of the most beautiful "house plants" wont' live well without lots of water but teaching that to growers is often tough.

I often wonder why I read the same bad advice over and over and people always seem to just step in line and watch their plants decline without taking into consideration where or how they grow in nature. Orchids are a great example since the majority live in very damp forests where it rains often but people even say "don't mist your orchids or let the leaves get wet"! How does nature rain on plants for hours at a time day after day in 100% humidity without getting the leaves wet?

Another poster on a different form actually wrote that Epiphyllum species (rain forest cactus) don't actually live in a rain forest. He claimed they somehow live only on the fringes of rain forests and don't qualify as a rain forest plant despite the fact they only live naturally in rain forests and many rain forest botanists say otherwise in their published writings. It just appears he doesn't want to water his plants so he came up with a "good reason".

Some advice just doesn't make sense which prompted my inquiry. I'd still like to hear more!!

There has to be a source for all this commonly spread info somewhere!

"People are idiots. But, I wander off topic"
I couldn't agree more.

I believe that the watering myths come down to the store bought soil mixes that are commonly available. Some of that stuff is like a sponge and you just can really water the way nature does if you use it. You stick your finger in it and it's still wet from watering two weeks ago. then when you get the fungus gnats away from your face you look at the plant and see it drooping and you want to water it more.

The compost and peat mixes by themselves don't let any air in if you water alot either so if you just dribble a little bit in at a time you can get by for a while, at least if you still don't water too often.

Not to mention the barely usable info on the tags many plants are sold with. A lot of them don't even say what the plant is, just "clean air plant" or "Foliage" or something equally useless. How about all the over priced books at the home centers where most people seem to be buying plants at nowadays with all the big pretty pictures and crappy worthless information(am I sounding too cynical yet) that keep people, if not actually killing the plants, from having a thriving plant collection.

I was at a HD not long ago and they had a truckload of ZZ plants, not a lable on any of them. I over-heard a woman asking a staff person about it and he didn't know what it was or how to take care of it. He asked another staff person and another, no one knew anything about them. At last they admitted not know instead of making something up but how are people suposed to know about proper care when this is an example of our most common suppliers.

oh well, rant is over. . .

You are certainly correct on those observations.

Soil composition, temperature, humidity, light and adequate water are the most important factors in making a tropical plant prosper. Peat is an important additive but so are Perlite, orchid bark, charcoal, finely cut sphagnum moss, mulch, compost and other additives to make the soil tropical in composition. One of the goals of my proposed article is to explain why the "stuff" you buy as "plant soil" in a store is near worthless.

The bigger problem is to make people spend the time and effort to learn about the plant BEFORE they buy it. I always hate to read a grower's post saying a plant is about to die and it is obvious the plant is "dieing" it is being "killed". But even worse is when the concerned grower is given advice that will only speed the death of the plant.

Most growers appear to just want the plant to "do its thing" and look pretty without any effort on their part. If a plant lives part of the year very wet and part of the year very dry as does the "ZZ" growers need to know that. Instead, what they normally hear from the store people is "don't water it very often" if they receive any advice at all. But a bigger problem is the ZZ is a very special plant and is not like the majority of South and Central American or Asia tropicals.

Forgive me, but now I'm going to rant!

There is a great source of info out there however that anyone can use. You can read most of it for free but if you want even more good info you can get it by just joining the International Aroid Society. You can find the IAS site at www.Aroid.org

There is a search feature on the left of the page and if you are an IAS member you can find the Trading Post where you can trade for free plants. Sometimes members even offer plants for free if you just pay the shipping cost or make a negotiated donation to the IAS. That feature plus the 10% discount on plant purchases offered to IAS members makes the small membership cost of no consequence!

If you join you can also take advantage of the publications members receive each year including Aroideana and the quarterly newsletters. You can read about those on the link below. I'm sure some of the readers will find the technical info "over their heads" but by using the IAS Facebook account you can ask questions and receive answers, often from very qualified botanists.

Rant over.

Now, back to the subject at hand. I think you are dead-on accurate but I'm still trying to figure out "where" all this bad info originated. There must be a book or some source out there that is spreading it. If any of you have a suggestion I'd really like to track it down.

Thanks for the assist but please don't stop there! A few years ago I was among the worst growers in the world but now have an atrium with plants so large I'm constantly giving cuttings away. All I did was "read" before I "bought".

I'd just like to figure out how to explain that to others and kill all the myths. Sites like this are very important to achieving that goal!

By the way, forgive me for my biased promotion of the IAS but I serve on the board of governors and the majority of my plants wouldn't be alive today if some of the smartest members and botanists in the IAS hadn't taken the time to teach how they should be grown. i use to believe every single thing I read in some of the "books" you spoke about until I learned some of them didn't "have a clue".

I just want to share the favor my IAS friends extended.

Here is a link that might be useful: Join the IAS

Hi
On my several trips to Costa Rica I was SHOCKED at the variation of the various climate zones.Due not to location but to altitude and the tropical cnvergence zones.
So in an area the size of West Virginia there are 12 distinct grow areas. Dictated not by season but by altitude and rainfall. How much and how often. So you have areas with as little as 10 to over 300 inches per year also divided by seasonal variation depending on the height of the mountain and which side. Temps dropping by about 5 degrees per thousand feet of altitude.
you will find none of the plants at low altide growing at high altitude from temps alone not to mention water.
The areas are divided into wet/wet wet/dry dry /wet.
yearly variation due to tropical activity.
Another fascinating aspect was micro climates generated by waterfalls, volcanic activity, fresh water as well as sw activity
To me one of the most fascinating was a lowland FW swamp inundated twice a day by tides. You could lay a straight edged on the limits of the SW intrusion and by elevation. You'd think NOTHING would grow in these conditions. Was equaally as lush as the rapid elevation areas but entirely different plants!!
Another was water plants growing in the trees.
Most fascinating microclimate I found !!
Another was Monte Verde listed as "true Montane rainforest" Record high 76 record low 46 average 50/68 year around rainfall average 250 inches Humidity 75 percent day night 90. Average direct sunshine 3.5 days without sunshine 5 Talk about a greenhouse??
I was hoping to gain some natural grow methods for my own use but found the climate MUCH to complex to be useful. particularly for orchids. I would NOT grow any of mine using that tiny experience for sure.
Ask me about the diversity of epiphytes in a given area?? Mind boggling. Okay will shut up now lol.
Easy to see why there are so many species in such a small area though gary

Gary, you and I need to sit and talk! You are both extremely observant as well as more than accurate!

Plants are extremely variable and some manage to live well in zones ranging from those near the sea to well up into the wet rain forest. But not all species are so tolerant and many live in very narrow climatic regions based on their requirements for temperature, humidity, rain fall (or lack thereof) and many other considerations. Although I grow over 300 species of rain forest plants there are many (including some orchids) I won't touch since I know I'll never be able to duplicate what they need.

As growers we want to lump all those "tropical" plants into one single group and treat them all exactly the same. We assume that if some (such as Spathiphyllum) can live with little water then all the plants in the forest should be able to do the same. Most growers want to take the easy route and not spend the time to learn about their plants and how any particular species lives in the forest. Worse, we want to "dump" all of them into off the shelf potting soil that is consistently soggy if wet and force them to survive on our terms, not their's. Too many of us want to just water once or twice a month and hope the plant survives.

I just read a note today from a grower that was trying to explain that once a plant is removed from the forest it doesn't respond the same to water because South America doesn't have a winter. Her reasoning appeared to be the plants will miraculously change to live the way we want them to live just because we take them from their normal domains. I find that curious since my personal collection lives and grows just like a rain forest despite the season of the year and I'm in Arkansas! Sure, some plants don't flower as often and others don't grow as rapidly, but they don't go "dormant" during the winter! Her reasoning was the plants don't need water because it is "winter" and somehow that should change the genetic makeup of the plant.
Take a look at the big photo on the home page of my website just down the page from the top. That photo was taken in February of 2009! It might have been winter outside but the plants just don't care because they get the light, humidity and water they need every day.

If you've ever been to a good tropical botanical garden such as the Royal Botanic Garden Kew in London or the Missouri Botanical Garden in St. Louis you won't see much of a difference in the way the plants look in summer or winter other than flowering. That's because the curators of the garden treat their plants as if they are still in the rain forest! They still water, provide humidity and good light. I really wish I could figure out a way to get this across to home growers! Just because it is winter outside doesn't mean your plants still don't need water!

You've just outlined much of what I hope to be able to explain in my article. There are plants that will live well with little water but that doesn't mean "all" tropical plants will live well with little to no water. In fact, many of the recently popular plants such as Anthurium veitchii, Philodendron gloriosum and others which have been sold recently won't live dry at all! They just croak and the grower never bothers to try to learn why or how to grow it!

Some Anthurium species do OK if kept dry (a few love it) but the majority need lots of water. The only way a grower can know that is to study the plant before attempting to grow it.

Your notes are very valuable to this discussion. Natural variation is extremely wide spread through the forest and growers need to learn about those conditions before buying any species. Just because the leaves look "pretty" doesn't mean a grower should buy it!

Great observations! If we could get growers to understand the forest and all its zones we might be able to help people keep plants healthy! Please continue!!!

By the way, the solution to the problem of watering is the soil! I'm in hope someone will comment about "soil" and then we may be able to get to the bottom of the issue.

Here is a link that might be useful: A rain forest under glass in Arkansas

Hey Steve, You need to be writing a book, not a magazine artical.

We did discuss soil a bit. I started out way back in the day using the store bought stuff. It seemed too silty(powdery) and I didn't, and still don't like the look of perlite as it floats around the top of the pot. worse yet was when it had those little piecs of styrene foam mixed in it. For a long time I mixed compost, peat and sand 1-1-1 ratio and it worked more or less for most of the plants I had but as I took the time to learn more I felt it too was too fine so I traded shredded bark for the sand and this seems to work fine for me. sometimes I use a store bought organic mix rather than top soil and peat or sometimes I add sand or vermiculite but the basic mix is sorta the same most of the time. The few orchids and cactus I have get something else when needed.

Here's the stituation for most people as I see it. They go somewhere, the store, home-center, whatever, See a plant that catches their eye and buys it. Or, they get one as a gift. Looks on the lable that say's water when dry. sun, shade, etc. with nothing else on it and that's what they do. things are going ok so they keep at it, maybe get some more and then things start going wrong. Then they may start to study up on what they've gotten into. In my opinion, it's ok for folks not to know much about the plants if they don't want to but the care tags need to be better and more informative and of corse better soil quality. If people go look at what is avialable and go away and get the info. it may be gone when the come back or they may just change their mind about it, the trick is to provide the proper info right there at the point of sale.

Now if you can get the growers to do something about the mud they plant everything in, well that would be something.

I also suspect that the answer to you original question may be from back in the day when there were only really a few varieties of plants most people have in theirs homes. Those plant were weeded out to take abuse. now there's so many more hybrids and species and information then just 15 - 20 years ago. I don't know if you can track down where the bad info came from in the first place.

Hi
two ?? about tropical grow zones in general are so contradictory to my own experience at growing plants .
Would love to find more info.
First on the Amazon basin. Have seen pix of areas where there was 70 feet difference between high and low water levels. Fish were picking at Bromeliads growing in the usual way attached to a tree.. Not only was the Brom underwater but so was the tree at a depth of at least 20 feet. How does the Brom or the tree for that matter tolerate this?? Are they annual??. Broms I could see popping up from seed during the dry season but doubt the tree would grow that much. I find many Brom VERY intolerant of water. even those that collect rainwater do not like roots submerged. Know of no specie of tree that grows totally submerged.?? The pix are always centered on the fish usually Piranhas and fail to give the slightest mention of the "Miracle" going on iin the background lol
Other ?? Why in place of ideal grow conditions such as rainforests have far less total # of specie?? Why doesn't the fastest most adaptable plant gobble up all the space??
I'm sure we've all experienced that in our gardens.??
We usually call them "weeds" barring a major frost I'm constantly having that problem with "tropicals"
As a temperate example when you go into a forest. It is dominated by hardwoods, pines, giant redwoods what have you obviously dictated by the climate.
In Costa Rica I could count at least 15 species of trees that I know grow to be giants with a casual look around. I frequently found areas so LUSH I thought for sure they had been "lanscaped" There is NO WAY you could have that many kinds of plants in such a small area!! lol
Okay I guess the BIG ?? is how come that tree that grows into a monster in my yard shares it's area with dozens of other plants?? lol

You guys have made a huge grin form on my face! Now we're getting to the bottom of what I want to explain and you're feeding me notes that will make what I want to write so much more useful.

I have a very busy day since I've got a worker coming to help move and hang a number of very large new plants that need to be hung from the ceiling of the atrium due to their size. I'm going to "digest" all of this and will do my best to feed answers to some of your questions as well as form some questions for your response later in the day.

As for the "book", I'm working on one. I have a couple of botanists that have been urging me to write the thing and as a retired photographer I don't have any problem doing the photo work. Maybe someday before I croak!

Thanks! I'll be back!!

I was really hoping for more input from a bunch of people on this subject but it appears it is time to wrap this one up.

Since most people don't really want to bother with ever watering their plants, many people go into a garden store and a very rich potting soil that stays soggy all the time. As a result you may eventually kill your plant. Many plant species can literally drown in mucky soil! For some unexplained reason many growers believe the rich soil makes a plant grow better!

Typical "potting soils" just don't work for the vast majority of tropical plant species since most grow in trees, not in soggy soil. The roots of many tropical plants are designed to*collect rain water during the wet season and suffer through the dry season. But even in the dry season a specimen can collect enough water from the humidity around their exposed roots to survive.
* Although house plant growers commonly believe tropical plants do not need water in winter that belief is simply a myth. Tropical plants live in very humid conditions and are capable of gathering water directly from the air even during the drier portions of the year when it doesn't rain on a daily basis. Dew and fog are very important contributors to the water available to a tropical rain forest plant species and homes don't have dew or fog! If we deny the plant the water they crave they only suffer and will never be able to display their natural beauty. In the temperate rain forest the amount of water available from the dew alone is estimated to be between three to five percent of the total annual precipitation! As a result, your tropical plants need water year round but it is wise to reduce the amount offered during the winter.

We water every week of the year averaging four days a week in summer and three days per week in winter. As can be seen in the photo the plants love water.

Despite the belief of far too many growers, growing plants is not just about the water content of the soil! The advice to water only once a week and keep the top two inches of the soil dry is not always good advice! Many aroids and other plant species grow in very wet soil!

Instead it is about the fast flow of water through the soil or the lack thereof which causes a lack of oxygen, anerobic fermentation and saprophytes which turn into pathogens. Saprophytes are organisms including fungus or bacteria that grow on and draw nourishment from dead or decaying organic matter which often includes soggy wet soil. The pathogens attack the roots and cause them to rot so all of the advice to "slow down on the water" is really about how to control the pathogens.

Fermentation and saprophytes often occur in muddy soil that will not not allow the roots to breathe but they don't necessarily occur in water which is why we can cause a plant that is about to die to grow new roots in clean water. As a result, it is necessary to use soil mixes that allow the roots to breathe and will not remain soggy.

I've attempted in many threads to explain the necessity of mixing proper soil for plants but the advice is often ignored since it requires some "work" on the part of the plant's keeper. The reason plants rot is not the amount of water given to the plant! These are rain forest plants and are literally drowned for months at a time!

If you could visit a rain forest you would quickly learn the soil is composed of leaf litter, decaying wood, compost and the charcoal left behind when a part of the forest burns. If we'll just listen to Mother Nature we can all make our plants grow as they should in nature. That is precisely what I attempt to explain when I recommend mixing soil, not just buying a bag at the store.

Over time we've developed a soil mixture for most of our aroid and tropical species. We use this mixture on the advice of the aroid keepers at the Missouri Botanical Garden in St. Louis. The goal of this mix is to allow the roots to freely find places to extend and grow without constantly finding wet places where they will rot. This mix will remain damp but drain quickly.

Rather than using a rich, soggy soil and watering only once a week (or less), use a soil that holds moisture well but drains quickly. With the help of botanical garden researchers we've developed a soil mixture*for most of our specimens that works great. People who visit our artificial rain forest are often amazed at the size of many of our specimens which grow much faster and larger than they often do in a home.

The exact mixture is not critical but we use*roughly 40% potting mix combined with 20% high quality peat moss, 20% orchid potting media containing charcoal, hard wood and gravel), and the balance cypress mulch mixed, with 10% Perlite and finely shredded pieces of sphagnum moss. We often add extra charcoal such as aquarium charcoal or hardwood charcoal to help purify the soil and sometimes volcanic rock If you are concerned about your soil remaining wet just add more orchid mix, cypress mulch, Perlite and sphagnum moss.

We grow many different species in this basic mixture and*some of our specimens have reached their adult or near adult size and regularly produce a spathe and spadix (inflorescence). *The goal of*our mixture is to cause the water to flow through the soil quickly, remain slightly damp, but never soggy. The roots of our plants attach to the bark just as they do in nature*on the side of a tree. Most growers call a mix similar to the one we use a "jungle mix".

Again, I welcome your input. We also openly invite anyone living or visiting in MidAmerica to visit our private botanical garden. There is never a charge.

You can see photos on the homepage of our website.

There's a guy who posts on the houseplant and container gardening forums under the name "TapAl", I think he is primarily a bonsai grower who I half expected to chime in here. He has posted extensively about soil composition and mixes (maybe he doesn't read the aroid forum) and seems to have developed a large fan base for the info he shares and the soil mixes he comes up with. He explanes clearly why things happen the way they do in the soil mix which can be useful in trying to come up with a mix that works well for you although my mixes are probably closer to what you recommend then his I still find his posts useful.

Another thing there seems to be a lot of confusion on is the idea of going organic with potted plants or inorganic since maintaining a reliable microcosm in a pot can be quite a challenge.

Thank you for this thread! I'm a botanist and gardener/designer focused in very different areas, but to make a bit of money, I also [work at a florist]. Sorry....

The plant manager I work with has been in the greenhouse and tropical business for almost 40 years, and has a local reputation as the plant doctor. Yet when a customer brings in a plant problem of almost any flavor, unless there is sign of definite insects/disease, his first 'default' is overwatering....

For a while, I thought he was nuts. But he is most often right, as the plants recover and thrive.

I've learned that the growers use a soil mix that retains as much water as possible, and drains, pretty much and sort of. Allows them to water uniformly and perhaps less often in a greenhouse with a large variety of plants, and certainly the method is cheaper.

But very often, with these purchased plants, even a moisture-loving tropical can decline from lack of humidity overall, and the owner waters more, and the roots decline and become diseased, and the leaves droop more from 'lack of water' because the roots are rotting and cannot transport water, so the owner waters more, and so on....

The houseplants I keep at home are the odd ones, and I research them, but at the florist job, I see endless Spaths and Diefs and Crotons and Ficus and so on from commercial growers going out the door to people who have no clue.

Thank you for the thread. I have learned a great deal.