Anthurium from seeds?  Two truly strange questions I've personally been asked many times are "can I grow an Anthurium in water" and "please tell me the names all the aquatic Anthurium species"? According to Dr. Croat (see his credits at the top of this page) there is really no such thing as an aquatic Anthurium  although there are rheophytic species that grow attached to rocks in fast moving streams. 

In nature you may find species growing near water but no identified species grows rooted in the water year round.  Some grow in water during the middle of the rainy season when the ground is flooded and are obviously water tolerant.  The rainy season does not last all year and once the flood waters recede the plants go back to their normal growth.  There is one species that has yet to be described to science located in Peru that does grow in creeks but it also grows in soil.  Species such as Anthurium sagittatum can live in drainage ditches but this type of growth is not common.  As a result I cannot recommend trying to grow any garden center Anthurium in an aquarium or water vase.

 

Dr. Croat is recognized as the world's leading authority on the genus Anthurium.  Of modern experts he has discovered, named and described more species than any other scientist having personally collected more than 100,000 plant specimens in the wild.

Anthurium species are found throughout southern Mexico, Central America and much of tropical South America with a few species found in the West Indies (Caribbean).  The vast majority of the most beautiful forms are located on the western slopes of the Andes Mountains within the rain forests of Ecuador and Colombia.  Those species are also widely variable and it is not uncommon for a single species to produce more than one leaf form.  You can find an explanation of "variability" here: Natural variability

Despite a number of articles on the internet that claim up to fifty Anthurium species are found in Southeast Asia according to science none are native in that part of the world.  One internet "encyclopedia" appears to be the source of this dubious information.  Aroid expert Julius Boos explains, "Anthurium is a Neotropical genus and does not occur naturally anywhere outside the Neotropics!"  The Neotropics is defined as South and Central America. part of Mexico and the West Indies. 

Any Anthurium species found in Asia, the South Pacific, or an Indonesian rain forest would have been introduced by plant collectors.    Julius' information is verified in many of the published papers written by Dr. Croat.  Plants from the genus Anthurium can be now found on many South Pacific islands but only as an introduced species.  In Hawaii many can be found in cultivation since the genus is used to hybridize variations that are commonly sold in garden centers.  Anthurium plants are a major export product for the Hawaiian islands but none live naturally in Hawaii.   http://www.aroid.org/genera/anthurium/abstrap1.htm

How do Anthurium grow naturally?

Anthurium species are grown more like orchids than perhaps any other tropical plant.  These plant species need frequent dampening of the roots but they must also be allowed to dry quickly.  An important fact anyone interested in Anthurium species must understand is only a few Anthurium species grow in the ground in the rain forest!  The majority grow up on the sides of trees or up in the canopy well above the ground.  Even many of gigantic "birds nest" forms grow on the limb of a tree not in the soil, but they can be taught to live in soil! 

So why do they live high in the rain forest canopy?  It rains!  And the rain is often followed by a drying breeze.  Most live on the branch of a tree but can be grown in soil.  Some Anthurium species grow on stone but unless you have the facilities to properly grow Anthurium in this manner the method cam be very difficult to maintain.  A few live in hot drier rain forest regions but those are not as common in collections. 

 

The ones that grow on trees are scientifically known as either epiphytes or hemiepiphytes.   An epiphyte (ep-a-FIT) is a plant that grows upon another plant, normally a tree.  They grow in the trees because the seed berries eaten by a bird or animal is then left on a tree branch in the animal's droppings.  Those seeds find just enough nutrients in the droppings to germinate and begin to grow.

 

Some eventually drop roots all the way to the soil and once they pick up extra water and nutrients grow very large.  Others known as hemiepiphytes are epiphytic for a part of their life and begin life in the soil and then climb a tree.   While epiphytes are already closer to the sun due to the point where the seed was placed by a rain forest animal the seed of a hemiepiphyte must seek out the light but does so by seeking darkness first.  It appears their own DNA directs them towards the shade of a tree so they can begin their climb toward the light and to adulthood.

 

Dr. Croat explains,  "I suspect it is auxin controlled. As you may imagine younger plants grow scototropically one assumes because they have to find a tree, rock or wall. Once there they stop growing horizontally and grow upward, effectively toward the light, rather than away from the light."   Scototropic refers to the behavior of a tropical seedling vine that grows toward dark objects. The plant does this as an adaptive characteristic that enables the young vine to grow towards the trunk shade of a large tree so it can eventually begin to climb in order to find brighter light. Auxins are plant hormones that control the behavioral processes of the plant.  An Anthurium is not a parasite and draws nothing from the tree, it simply uses the host for support.

Hybrid and "test tube" Anthurium.

Anthurium species are very popular as house plants.  Almost anyone who goes on vacation to Hawaii is at least tempted to bring home an Anthurium.  The vast majority of the plants grown in Hawaii are hybrid varieties and not species.  Most are hybridized from a species known to science as Anthurium andreanum (see photo of hybrid form at the top of this page).   That species is found in northwest Ecuador and  western Colombia, but it is popular for  hybrid 'house plants' since it produces a colorful spathe.  

A hybridized plant is one that is created by taking the pollen of one species and applying it to the spadix of another species in order to produce a plant that is "improved" or better, at least in the opinion of the hybridizer.  In fact, the cross may produce a plant that has larger leaves, larger inflorescences, and inflorescence colors not seen in nature.  But that hybrid is no longer either species.  Lots of hybridizers grow their plants the old fashioned way and are constantly crossing pollen between species or other hybrids that are not sterile.  They then grow the seeds to produce their plants.

Even more important to large commercial growers is the fact they want you to see the plant filled with inflorescences in the store!  Commercial growers often use a chemical known as gibberellic acid (often sold as GA3) to induce the plants to produce more inflorescences in order to make it more saleable at the time you are ready to buy.  Gibberellic acid is a natural plant hormone and is used in larger than normal amounts in agriculture to stimulate both cell division and cell elongation that affects the leaves as well as stems of a plant.  The continued use of the chemical in agriculture eventually affects fruit development.  Since the fruit of an aroid is produced on the spadix gibberellic acid is capable of speeding up the the production of inflorescences.  In many cases the Anthurium can become addicted to the chemical and once you get it home the plant may produce far less inflorescences than you expect.  Since you have no GA3 to continue giving the plant its "fix" it may not produce the colorful inflorescences as often.  Gibberellic acid has also been proven to produce badly formed spathes, double spathes, strangely shaped leaves and other malformations.  For that reason alone the plant needs near ideal conditions to keep it happy.  One caution.  GA3 can have unwanted consequences including the death of the plant and should not be used by home growers in almost all cases.  But if you've wondered why your Anthurium no longer will produce an inflorescence you may now know the reason.

There is nothing wrong with buying a hybrid plant but here's one important note on buying hybrid specimens in a retail store.  Do not rely on the advice of a sales person to grow your plant unless you know for certain they are an expert in this genus!  Most know nothing about Anthurium species and advice such as allow it to dry out completely before watering again or water it sparingly is bad information.  There are a few species that like to dry between watering but those are not the common hybrids found in retail stores!  Any suggestion you use off the shelf potting soil is also very bad information and is a guarantee the sales person knows very little about Anthurium species. 

Commercial growers rarely include good growing instructions because their goal is to sell as many plants as possible.  If your specimen dies after you followed the store's instructions and you go out to buy a replacement guess who wins?   This is not a slam against the kind folks that work in retail garden centers but it is not in the best interest of the store to give you good advice so the plant will live a long time.  They like for you to come back and buy more plants!  As a result you will rarely find good growing information attached to the plant. 

The majority of Anthurium store bought plants are juvenile forms and look very little like the adult form of the species since Anthurium morph as they grow!  During the 18th and 19th centuries botanists were confused by the incredible differences in adult forms and juvenile forms and often tried to give each of them a different scientific name.  That is one reason some plants have more than one scientific name.  Those multiple names are known as synonyms and can be the source of a great deal of confusion among collectors.

 

How should an Anthurium be grown?

If you live in a tropical or semi-tropical climate you may be able to simply put your Anthurium  in the ground.  If it is an epiphyte it may try to climb a tree.  If it is a terrestrial form, give it lots of room since many of the "birds nest" species love to spread and can eventually grow leaves 6 feet long!  Otherwise proper potting of your specimen is very important if you want it to survive and grow to reach its potential natural beauty. 

 

I've seen go into a garden store and a buy very rich potting soil that stays soggy all the time.  In most cases the Anthurium will die a slow death since they literally drown!  For some reason people believe rich soil makes an Anthurium grow better but off-the-shelf "potting soils" just don't work for these species!  Remember, they  often grow in trees and don't exist in nature in wet soggy soil.  Their roots are designed to collect rain daily during the wet season and then suffer through the dry season.  If you were to go into the forest you would see the roots literally get plump as it rains!  Even in the dry season they can collect enough water from the humidity around their exposed roots to survive.  You can make your plants grow more beautifully and stay healthier if you learn to grow them as they would in their  natural habitat.  We've heard of many plants ending up in the trash from being subjected to too much water.

Some sellers provide Anthurium attached to volcanic rock.  There are species known to be epipetric that means they grow on stone.   Volcanic rock can work but you must keep those rocks constantly damp.  The plant will extract the necessary water from the interior of the porous rock but that does not mean to sit the plant in water.  Just keep the rocks wet.  No Anthurium species is known to grow in water despite what some websites and sellers try to make you believe. 
 

One method used by some serious collectors is to put the Anthurium in a large orchid basket packed with good quality sphagnum moss.  Since the plant normally lives in the top or on the side of a tree it can adapt to those conditions and we have a few plants growing on our epiphytic log with no soil at all but you must keep the moss constantly damp.  In our atrium we water the plants displayed in this manner almost daily!  However, we often leave any soil attached to their roots and do not remove it.  We simply pack the moss around the roots as well as mix the soil mixture we will describe with the moss.  We also cut the moss into very fine pieces.  In a few months you may begin to see the roots extending down through the moss and hanging out the bottom of the orchid basket that is very natural.  At one time one of our guests grabbed a pair of scissors and tried to cut them all off because she thought they looked bad.  I nearly screamed since this is the way Anthurium plants grow in the forest!  You should know this method is tricky to use and requires constant monitoring.

 

The majority of birds nest forms require a period of dryness in the forest in order to survive and prosper!  Be aware that far more bird's nest forms that are all members of Anthurium section Pachyneurium grow up in the trees than in soil! 
 

People who visit our artificial rain forest are often amazed at the size of many of our birds nest specimens that grow much faster and larger than they often do in many homes.  Our very large bird's nest forms hang from the ceiling in large orchid baskets that measure 30 x 30cm (12 inches square) with no soil at all since their roots are packed only in sphagnum moss! 

Soil mixture.

 

Despite the belief of far too many growers, successfully growing Anthurium and other aroids is not just about whether should you water or not water a plant or about the water content of the soil!  Many aroids including Anthurium grow in very wet soil!  Instead it is about how fast the water flows through the soil, or the lack thereof, that can cause a lack of oxygen, anerobic fermentation and saprophytes that turn into pathogens.  Saprophytes are organisms including fungus or bacteria that grow on and draw nourishment from dead or decaying organic matter that 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 and is why we can cause a plant that is about to die to grow new roots in a clean glass of 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 found a soil mixture that works for most of our Anthurium species.  We use this mixture on the advice of the aroid keepers at the Missouri Botanical Garden in St. Louis and grow close to 100 different Anthurium species.   Many of our specimens have reached or are beginning to reach their adult size and have produced inflorescences.  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.

 

The common advice on most garden websites is to allow a plant to dry between watering is not always good advice.  Anyone that has asthma knows the difficulty of getting air out and then drawing it back in.  A potted plant is much like your lungs.  As a result the top layer of a potted plant's soil should not be allowed to dry since that dry soil prevents the intake of fresh air including oxygen!  Although plants give off oxygen through their leaves they take in oxygen through the roots. 

 

Once the soil dries it creates a "blanket effect" to hold in the stale moisture and keep out fresh oxygen.  Once the upper soil dries the moist layer below cannot easily breathe in order to re-oxygenate the soil. The dry upper layer actually prevents the capillary effect of the wet surface evaporation when damp soil is exposed to air.  When you pour water in the soil the air inside the soil is displaced.  The oxygenated air inside has now left the pot. If the upper soil layer completely dries the "lungs" of the pot cannot work and can no longer continue to draw in another breath of fresh air.  As a result the entirety of the soil needs to remain evenly damp so the roots can continue to draw in fresh oxygen.  

Although we mix our soil based on how a species grows in nature we primarily use a very loose soil mix with 30 % Miracle Grow Moisture Control Potting Soil combined with 20% high quality peat moss, 40% orchid potting media that has hard wood, charcoal and gravel mixed with 10% Perlite™ that is combined and mixed thoroughly with a hand full or two of cedar mulch along with finely cut spahgnum moss.  The idea to include charcoal is to increase drainage but also to take advantage of the tiny air spaces in the charcoal for growing beneficial microbes.  It helps with water retention, as well.  If you have some good compost feel free to add it.  Small pieces of charcoal can be purchased from any good orchid supply.

 

We recently had a large walnut tree removed from our yard and once the stump was ground we composted the remains that are now being added to our soil.  Extra orchid or aquarium charcoal is also an excellent additive since it helps to purify the soil.  The exact mixture is not critical but all of these ingredients should be mixed as thoroughly as possible. 

Many growers call this type of mixture a "jungle mix" due to its similarity to the very loose soil in a rain forest.  The peat, orchid medium, charcoal, mulch, sphagnum and Perlite™ hold moisture and release it back to the roots as needed.  The other ingredients keep the soil loose and from becoming hard packed.  The roots of the plant will easily move through he mix and will also attach to the bark just as they do in nature on the side of a tree.  Depending on the species, we sometimes also add small pieces of crushed volcanic rock frequently sold in orchid supply stores. 

I've had "nursery experts" write to say this soil mixture won't work due to the orchid potting media and mulch.  They claim the bark and mulch will eventually rot and create air pockets in the soil and then kill the plant.  They need to tell that to the experts at botanical gardens such as the Missouri Botanical Garden in St. Louis that maintains one of the world's largest collection of Anthurium since they developed the mixture.  Botanical gardens in Florida, Europe and other parts of the United States us a similar mixture for almost all aroids.  We've been using it since 2003 and our Anthurium as well as Philodendron species just keep growing! 

Light intensity.

The next important consideration in Anthurium care is light.  In almost any rain forest, light is a very precious commodity!  Plants fight for position and large ones often deprive small specimens of any light at all!  Anthurium and other species climb trees to reach the light!  As they grow high on the side of the tree they morph into what often appears to be a totally different species!  Although a few, mostly with velvet textured leaves, prefer lower light lmost  Anthurium prefer bright indirect light.  Some will exist in deep shade like your living room but will not flourish.  Don't try to grow your Anthurium in a darkened corner, keep them near a window with bright diffused light.  Some can be trained to live in extremely bright light but very few will survive in direct sunlight.  If you are growing your Anthurium species outdoors keep them close to a tree that will allow them to have filtered sunlight.

 

Light bulbs just don't provide enough intensity or the right spectrum to keep an Anthurium specimen happy and healthy.  "Grow lights" may make them "grow", but won't make them flourish.  Filtered, relatively strong light is best.  The light coming through a window is much stronger than the light from a inflorescent tube.  Your plant will reward you with a dramatic change in the production of inflorescences and  leaf shape if you give it what it craves!
 

 

Water requirements.

 

Watering is important to the proper care of your Anthurium.  In our rain forest we sometimes water every other day of the week but we vary the water schedule to include more water in the heat of the summer and less in winter.  Some days we find it necessary to water twice daily.  Our system has an automatic overhead misting system that is designed to duplicate a rain forest.  Anthurium species are rain forest plants and receive frequent watering in their natural habitat.  But do not over water, just be sure and use a porous soil mix as described above and keep the plant humid with misting from a spray bottle.  You can also place a tray of water beneath the pot that will evaporate around the leaves to increase the humidity in the immediate area.

 

There are species that prefer a longer dry period including all the birds nest types and we attempt to segregate those during the winter season.  Section Pachyneurium species (birds nest types) must have a dry period and often go for a month or more with no water at all.   These species must have the dry period in order to remain viable.  It often rains daily in the "rain forest" for 9 months or more per year!  Most prefer to have their roots damp all the time, just not in soggy soil.  In your home, water often enough to keep the soil damp, but not soggy and make sure the pot can drain easily.   It is best to never use a pot that cannot drain but if you must use a pot with no drain holes in the bottom then add a minimum of three inches of gravel (non-limestone) beneath the soil mix so the water can drain.   We attempt to explain the details on individual species on each of our web pages. 

 

How much fertilizer and how often.

In nature an Anthurium receives only natural forms of fertilizer since there is no one in the forest to go around with a big bottle and sprinkle it on everything!  The epiphytic species can collect minerals in the rain that comes from the winds blowing across the Atlantic from Africa.  Those winds often bring dust from major dust storms in the African plains to the rain forests of tropical America and once it settles in the rain the long dangling roots of the plants can gather a small amount of dissolved minerals and nutrients.  They also gain fertilizer from decayed vegetation (leaves) that collects around their stems and roots but they receive nothing near the amount of fertilizer home growers are prone to give!  Excess fertilizer can kill your plant so don't use more than the manufacturer recommends.  In most cases use less! Less is much better than too much. 

 

Regarding fertilizers, aroid expert Julius Boos wrote, "It is also the epiphytic plants that benefit just as much from falling debris and rain! Many 'birds-nest" type plants actually grow on trunks and branches of trees.  In French Guyana we saw a species of Philodendron that grows like a vine up tree trunks, and when it reaches a suitable spot, changes form from a climbing vine and becomes a 'birds-nest', catching leaves.  It then creates an area where ants actually build their nest in the roots and amongst the leaves/debris mix. These ants also provide lots of fertilizer with their by-products, left-over insect and fruit parts, etc.. The rain also washes debris and the nitrogen it picks up and contains on to the long, pendent roots of other species."   Species, such as the terrestrial "birds nest" forms are designed to collect falling vegetation:  leaves and other debris.  In nature, those species will often be found with piles of dead leaves and other plant material inside their conical base.  That material then decays and the result is a natural form of fertilizer for the plant, especially when insects are invited to set up home.  But most collector/growers carefully collect and clean out all dead and decaying material found around their plant!  We are then depriving the plant of the natural form of fertilizer for the sake of "beauty".

 

As a result most experienced growers do not fertilize heavily or often.  Instead they fertilize sparingly.  Most adhere to the recommendation to  "fertilize weakly, weekly".  Simply that means adding a small amount of fertilizer to your water and give it to your plant often, best once each week.  A good recommendation is 20% of the manufacturer's recommended amount.  Large doses of artificial fertilizer do little to encourage the plant to grow as large as it will in nature but minimal doses of liquid fertilizers can cause your Anthurium to reach an unusually large size and beauty.  An alternate method used by successful commercial aroid growers is to use the pellet form of Osmocote 14-14-14 or Nutricote 13-13-13.  Osmocote is available at most home improvement stores while Nutricote is sold at agricultural suppliers.  The pellet fertilizer lasts 3 or more months and dissolves slowly.
 

You will achieve best growth if you use about 10% of the manufacturers recommended amount but give it to the plant more often than is recommended.  Fertilzer does not produce more frequent inflorescences!  Anthurium species are seasonal.  Some species freely produce an inflorescence any month of the year but others are designed by nature to only reproduce during a particular season of the year.
 

 

Magnesium in the form of Epsom's salt.

 

Anthurium species as well as many other tropical plants also enjoy an occasional dose of Magnesium.   This is easily supplied in the form of Epsom's Salt that is available at any garden center.  Using this product monthly will make the plants respond well.  Follow the manufacture's instructions (1 to 2 tablespoons per gallon of water) if you are using a garden sprayer but if you need to mix it in a glass add only 1/2  teaspoon to a large glass of water and use that for a single watering.  Give the balance to other plants or dispose of what the plant cannot absorb in a single watering.  Do not make the soil soggy.
 

 

The ideal temperatures.

All Anthurium species are tropical that means they can't tolerate really cold temperatures.  Some do live high in the Andes Mountains well above the cloud line and are "cool" loving species.  But they don't like cold!  The cloud forest species do not like heat and won't do well in an outdoor setting where the temperature may stay above 26.6C (80 degrees F) for long periods of time.  They can tolerate short spells of high temperatures, but some, such as Anthurium rugulosum, (photo left) may not survive.  Many growers of these cool loving species use a high humidity "wet wall" combined with a small air conditioning system to keep the ambient temperature low and the humidity high.  Many of these species will do well down to 4.45C (40 degrees Fahrenheit), but not much cooler.

 

As a rule never allow the temperature around most of your Anthurium specimens to drop below 12.75C (55 degrees F).   It is best to keep them well below 32C (90 degrees F) that is not particularly difficult if you grow them in some form of shade or filtered light.  Some species will tolerate short periods of cold like that found in Central Florida but most won't survive anywhere outdoors north of zone 9.  The are zone 10 and higher species!  Most will die quickly if exposed to a freeze.  Ssince most grow faster when the temperature is in the 21 to 29.5C (70 to 85 degree F) range you may find your specimen will appreciate being allowed to live outdoors during the spring and portions of the fall.

Humidity, a little or a lot?

 

Humidity is extremely important!  Do everything possible to keep the humidity high around your Anthurium.  These species live in a jungle that often has a humidity level near 100%!   If you live in a climate that has a low humidity such as southern California you will  need to provide a method to increase the humidity around your Anthurium.  In our artificial rain forest the humidity is always 85% or higher due to the waterfall and pond in the center of the room as well as frequent watering!  Some growers keep their Anthurium species near a swimming pool to allow for a constantly high humidity.   Air circulation is equally important since the air is almost always moving in the rain forest.  Avoid stagnant air since that may encourage mold, fungus and insect predators.

If you can't give the species rain forest humidity conditions then there is a simple alternative.  Place an attractive shallow dish filled with water beneath the plant's pot.  Fill that pan with gravel, preferably one that does not have too much limestone.  Fill the pan and gravel with water and then sit your plant and pot on top of this gravel bath in to create a micro-climate around the Anthurium.  It works!  Water will evaporate around the leaves and fool the plant into believing it is living in a humid rain forest environment.  When you water the excess will simply drain into the gravel pot. 

Why do you want to avoid limestone gravel?  If you use the soil mixture we suggest, you've just created a soil mixture with a pH below 7, likely around 6.5.  The Anthurium will appreciate that pH level!  If you add limestone to the mix, the pH can be raised to above 7 and the Anthurium is not as likely to appreciate that level with the exception of a few species that do live in higher soil pH areas of the tropics.

 

How do I know my plant is an Anthurium and not a Philodendron?

All aroids produce an inflorescence so the production of a spathe and spadix alone does not prove the plant is an Anthurium.   Anthurium species have two unique features that can easily be observed by a plant collector.  Those features are known as the geniculum and the collective vein and both can be seen on any Anthurium specimen.  The geniculum is located at the top of the petiole that is the stalk that supports each leaf.  The geniculum allows the leaf to rotate and orient itself in order to better collect sunlight.   The geniculum looks and works something like your knee or elbow.  Just like your elbow allows you to bend and rotate your arm the geniculum allows the leaf of an Anthurium to rotate itself up, down or from side to side.  The geniculum may be swollen and obvious in many species but barely noticeable except to the touch in others.   Aroid expert Julius Boos explains, "the geniculum acts like a ''wrist'', and actually allows the leaf blade to turn or rotate to align itself with the light source and occurs only on some aroid genera including Anthurium and Spathiphyllum but not on others."  

Any leaf contains several different vein forms.  The centralized rib vein is known as the mid rib and there are large veins known as the basal ribs, primary lateral veins, interprimary veins with the smaller known as the tertiary veins.  The tertiary veins are the repeatedly branched veins that arise from and are connected to the primary lateral and interprimary veins. The reticulate veins are the smallest visible vein form found within small areas called areoles (also a condition known as areolate). The primary lateral leaf veins on any Anthurium connect into that collective vein.  The area between the leaf lobes is known as the sinus.

The collective vein is a specialized vein submarginal vein found near edge of a leaf.  Collective veins come in pairs (one on each side of the leaf) and are simply the union of part of all of the primary lateral leaf veins that extend all the way to the tip of the leaf (apex). A submarginal vein that lies parallel as well as near the leaf margin (edge) into which the primary lateral veins run. The collective vein almost completely encircles the leaf in some species but in others begins approximately 1/3 down from the top of the blade and emerges from one of the primary lateral leaf veins to run around the bottom of the blade and up the opposite side to reconnect with a primary lateral leaf vein on the opposite side as a continuation of a primary lateral leaf vein.  Collective veins may be observed in Anthurium, Syngonium, Alocasia, Colocasia, Xanthosoma, Arisaema, some Amorphophallus as well as other genera.