On behalf of the International Waterlily & Water Gardening
Society [IWGS], I offer ongoing aquatic plant technical support
to the Aquascape, Inc. network of Certified Aquascape Contractors
[CAC]. This support is implemented through their internal message
board and is usually a very easy gig. Aquatic plant culture,
after all, is a fairly straightforward discipline with few surprises.
Keeping aquatic plants alive and flourishing is well within the
grasp of most anyone since most of the extant literature on this
subject is dedicated to their eradication rather than their well-being
Last month however, things got a bit thorny. The Republic
of Texas, which has an ego to match its square mileage ... just
had to have a Texas-sized problem with aquatic plants
Michael Nickles, owner of Paradise Ponds, a pond design and
build firm based in San Angelo, Texas USA (home of the International
Waterlily Collection [IWC]) posted this question on the CAC
message board on September 12:
Plants wont grow in pond
Large Pond 300'x 100' x 6' avg depth
System is 4 years old
Problem: Plants have failed to grow. Replanted multiple
times with various species. The only thing that has survived
are regular cattails (but they look weak and small) and a few
waterlilies (bloom rarely and have extremely small pads)
Pond is filled and maintained by two wells
Water testing from a laboratory revealed the following:
pH when received 7.66
Bicarbonate as HCO2 185
Total hardness as CaCO3 3060
Calcium as Ca 536
Magnesium as Mg 418
Sodium and/or potassium 809
Sulfate as SO4 2637
Chloride as Cl 1364
Iron as Fe 0.69
Total solids, calculated 5949
Phosphate as PO4 20ppm
Nitrate as N 1.5
Nitrite as N 0.0
(results reported as milligrams per liter)
So Stroupe ... What say you?
Stroupes putative solutions were quickly exhausted with
Where is this pond?
Sun or shade?
Water depth [planting]? Lilies and marginals ...
Time of year planted?
Possibility of herbicide contaminants?
Test pH again with just a simple test kit. High pH is the single
most common cause for this.
What about the soil the plants are potted in? Herbicide or other
contaminant residue possible there? Have you used the same soil
source each time?
Are you even using soil or are you planting directly in gravel
In the meantime I'll forward your test results over to
someone smart to look them over to see if any red flags appear,
and then we'll compare notes again ...
Mr. Nickels replied back quickly with this information;
Pond is located in Texas, zone 7
Full Sun except for a few perimeter trees
No herbicide contaminants
Bare root plants planted directly in gravel (as is every pond
I have done with the same plants from the same vendor)
Will check the pH again.
Plants have been introduced in the spring, summer, and
fall for three years with no success. Plants that normally "take
over" any other pond will die in a matter of days if not
one day. I watched ------ and water ------ die about 8 hours
My perhaps overly-confidant reply based solely on the morbidity
timeline of some of the deceased:
The death of ------ and ------ is probably unrelated to
the other plant deaths ... based on the info you've furnished.
This sounds like they got overheated in transit which will cause
them to crap out in a few hours after setting out, which is fairly
common even outside of Texas. They were "dead men walking"
when you got them I'm guessing.
We'll put them aside for now and concentrate on the waterlilies
My expert has already passed this off to another expert,
and I'm baffled, but we will throw this out to the entire international
water gardening community if need be ...
Nothing like a good "whodunnit".
My expert was Jim Purcell, co-owner of Oregon
Aquatics and a personal friend. He (much to my disappointment)
demurred, and passed this question off to Randy McDonald of McDonalds
Aquatic Nursery in Los Angeles, California USA, who replied thusly
Well, my thoughts on this, as I quickly review the information
given, is like a doctor looking at the laboratory results of
a blood test. I'm not used to such technical, chemical analysis
of pond water because, normally problems such as these, are easily
interpreted without all of this extra work, at least for me!
In any case, the first thing that is a red flag for me is the
fact that the relationship of calcium and magnesium is way out
of whack. The ratio of magnesium to calcium cannot be any tighter
than 3 to 1, calcium to magnesium and ideally 4 to 1. This water
sample is very close to one to one which would definitely lead
to dwarfing (stunting), and, or, contorted, deformed growth at
best. Any good growth for any type of water plants, or even terrestrial
plants with this ratio of calcium to magnesium would be a violation
of everything that has been published in regard to this critical
balance of these salts (ions when in solution).
The second thing that disturbs me about the pond is the
bottom aeration. As I'm sure you know, cattails, lilies, and
other true aquatics are adapted to and even prefer a bottom substrate
that is not aerated, in fact, the more anaerobic conditions I
give cattails and waterlilies, the better, faster, and stronger
the growth. Just recently I tested this on viviparous leaf production
of lilies. Tiny lilies that normally take a long time to develop
under more aerobic conditions, developed and grew large in anaerobic
conditions in a fraction of the usual time.
The third thing is that all of this filtration can only
lead to a lack of ammonium for the nitrogen source for the plants'
use. Everything in the way of nitrogen would only be available
in the form of nitrates, something only terrestrial plants and
algae like and use as their nitrogen source. So, another nail
placed in the coffin of trying to get the plants to grow normally.
Waterlilies and cattails prefer a backwater condition to grow
normally. Most people in the trade know this as it is pretty
well outlined in every book on the subject. The reasons aren't
ever given in these books as to why this is true, which is baffling
to me. It might help with the thought processes in the arrival
to solving such problems as you are writing about. One fact remains
after all is said and done. They like the backwaters, the sedimentary
areas of deposition of both organic matter and colloidal particles,
because that is where the anaerobic conditions occur, which lead
to all of the chemical properties and bacterial interactions
that they need, as dictated thru the millennium of time. This
leads me to state my conclusion to the above information: "When
in doubt to why a pond isn't working, in regards to growing plants,
look and study a real pond." What they have created in this
scenario is a pond that is perfect for the breeding and culture
of fish, not plants.
At this point ... being way out of my normal operating bandwidth,
I thought Id present this problem to the 2000+ member Water
Gardeners International/Victoria Adventure group online.
Chantal Piefer of Houston, Texas USA, responded to Randys
second-hand post with these observations:
Very good point. In what part of Texas is this pond? Parts
of Texas are highly alkaline, meaning plants go chlorotic and
have limited access to the nutrients they need, especially iron
uptake. Texas A&M in College Station is in one of the areas
that is highly alkaline and I think they RO (reverse osmosis)
their water for the greenhouses. Also well water tends to be
much more mineralized -- could rainwater be collected to feed
the pond? I can imagine that the evaporation they get and the
constant topping off just increase hardness. Also what's the
substrate of the pond -- if it's gravel, it should be something
that doesn't contribute to hardness, etc. Limestone would be
inappropriate. If it's concrete, there a general curing process
(I'm not exactly familiar with it but vinegar or acid baths are
involved) that helps to remove excess lime. If it's earthen,
test the soil. Someone familiar with really controlling water
conditions may be able to recommend a scheme for bringing pH
and harness under control, but, at that volume, I can't imagine
it would be cost effective.
Let us know how this goes. Good luck.
Then AJ Hicks, Chandler, Arizona USA had this to say;
If it were me, I'd haul a few buckets of the stuff off-site
and put them side-by-side with buckets of plants grown in water
from another source. If the prolific floating plants (water hyacinth
and water lettuce) expire horribly at the CSI pond, then surely
they would make for excellent experimental species.
You might also consult with agricultural or water quality
people -- probably even the same ones who did the test. See if
they think it's too salty to grow stuff.
Or, heck. What does it taste like?
Bicarbonate as HCO2 185
Total hardness as CaCO3 3060
Calcium as Ca 536
Magnesium as Mg 418
Sodium and/or potassium 809
Sulfate as SO4 2637
Chloride as Cl 1364
Iron as Fe 0.69
Total solids, calculated 5949
Phosphate as PO4 20ppm
Nitrate as N 1.5
Nitrite as N 0.0
So -- low nitrate and nitrite indicate it's not surface
water, or there'd probably be a good slug of N -- more than 1.5
ppm combined anyway. Plus, the other dissolved components are
more representative of saltwater intrusion. How far is this from
the coast, and how much pumping are they doing locally?
Note that as a "secondary standard" (mainly for
taste and appearance), sulfate is limited at 250 ppm:
Which puts the sulfate in the water sample in the "holy
cow" bracket. Iron is more than twice the secondary standard.
Chloride is more than five times the standard. Total dissolved
solids are capped at 500 ppm, or about 1/12th that of the calculated
quantity from the water sample.
Now that I look at it real hard and squint a bit -- yeah.
It's saltwater intrusion. There's no other way to get such a
spectrum of ions like that, in those strengths. The only other
way would be some sort of drilling thing, i.e.: some drilling
rig hit a salt dome and there was groundwater intrusion which
has spilled over into the wells. Or maybe a hurricane storm surge
or something like that, but it's some bad saltwater damage that's
killing those plants. It's pretty obvious now that I look at
those values again. The mix of values (versus "pure"
sodium + chloride, because there's lots of
sulfate, lots of calcium, lots of magnesium) leads me to believe
from ocean water rather than a subterranean salt dome.
So- where do I send the bill for my consulting fee? :D
Not a geologist, but I play one o -- no, scratch that.
I'm a geologist.
Now this is starting to get interesting as well as fun ...
Ive successfully diverted attention from my rather glaring
inability to solve this problem, and have managed to successfully
engage some real professionals in the process. I feel a bit like
Huckleberry Finn whitewashing the fence...
An interesting observation came in from Cologne, [with water
as hard as nails] Germany, from Jamie Vande who wrote:
Assuming the readings for ions is ppm, the Ca+ level is
very high for fresh water. Marine water has 420ppm and is considered
high. The pH is too high for many plants as most stop growing
around 7.4. The readings for hardness cannot be correct! The
level noted would be cement! There is certainly a decimal point
of mismeasurement in there. Hardness is typically measured in
dGH or ppm. Extremely hard water has a dGH of 30 and 530ppm.
Also, with the given Ca+ reading, the Mg+ reading is very
weird. Mg+ is normally higher than Ca+.
In general, the readings given are suspect to me. Whatever
they actually are, I believe the problem is the hardness and
pH. Where did this water come from? Something has definitely
Hope this helps.
town with water as hard as nails
This is really cool! People from all over the world are starting
to contribute their expertise to help a Texas contractor solve
his problem with dying pond plants ...
My response to AJ -- and I hope Ive managed to reconstruct
these responses in something relatively close to chronological
Thanks AJ...How could one determine if these combinations
produced conditions which were too salty to support plant growth?
Provided the plants are getting enough sunlight, I'd ask
1) What's the water temperature? Is there any chance the
well water is being pumped so fast the pond isn't getting warm
2) What happens when pot plants are watered (and showered
-- leaf exposure would be required) with the same water?
3) The water has too many ions in it. I'm thinking either
it's too cold, or there's herbicide contamination. However, TDS
is awful high. There may be another reactive species in there
that doesn't come to mind immediately. Check with the local agricultural
guys or the state water bureau, and see if there's something
peculiar about that specific location. I mean -- combined sodium
and potassium at 809 ppm is interesting, but -- heck, I'm sure
some folks in Florida would have a chuckle at that level being
AJ almost sounds like Columbo (lead character in another
American TV show) with that folksy, homespun, aw shucks
demeanor, coupled with what is obviously a high degree of technical
proficiency and a generous willingness to share it ...
Wishing to somehow remain engaged with all of these exceedingly
intelligent and well-informed folks, I then offered the following
supplemental information after a bit of research based on AJs
theory and a further consult with Michael Nickles:
The pond (see photo) is located in west Texas in the heart
of the Permian Basin. Potassium salts (potash) are mined from
this area which is also dotted with oil and gas wells. The pond
is approximately 75 miles due east of the southeastern corner
of New Mexico and is quite a distance from the Gulf of Mexico.
All of the terrestrial landscape plants receive 90% of their
water from overhead irrigation with water from this same well.
According to the contractor, even salt-sensitive plants such
as crepe myrtle show no adverse effects from the watering. The
pond water will be retested shortly in order to compare results
with the first test.
A similar pond less than half a mile away has flourishing aquatic
plants with well water.
The floaters which deteriorated the same day they were placed
in this pond were brought from a location two hours away under
optimal conditions so they did not suffer from shipping trauma
as I previously thought ... there was something in the water
that effected their rapid deterioration within the same day.
Rich Sacher, hybridizer, water garden retailer, renaissance
man, and Hurricane Katrina survivor had this to contribute, which
he playfully titled, Jumping In with Aerobics:
This large Texas pond under discussion ... no one has said
(or I missed it) if it is a natural bottom pond, concrete or
liner. Sort of important to know. Also important ... are the
plants in pots ... are they ever fertilized ... or, if planted
in the pond bottom, is any supplemental fertilizer pushed in
among their roots?
I have noticed over the years that some smaller liner ponds,
when they have overly efficient biological filters, may be so
devoid of dissolved nutrients that hyacinths, water cabbage and
free floating anacharis will turn yellow and starve to death
in the crystal clear water. And of course, in the case of the
Texas pond, extremely high salt concentrations could tie up any
soil nutrients which would otherwise be available.
I disagree, however, with the statement that waterlilies
prefer anaerobic conditions. While there may be a wide range
of tolerance for anaerobic soil conditions among various water
plants, potted tropical waterlilies definitely prefer pots with
holes in their sides and near the bottom, to allow water passage
through the bottom root zone, thus providing aerobic conditions
in the soil. Here is why I believe this:
When unpotting tropicals at the end of the season, from
holeless pots only 10 inches (25 cm) deep, I would always find
the bottom 3-4 inches (7-10 cm) of soil to be black, smelly and
full of dead roots. The anaerobic conditions at the bottom of
the pot eventually killed off the roots in that zone, and their
slow rotting contributed to intensify the anaerobic condition.
This would happen to every waterlily by the end of our season,
every year, until I started perforating the pots.
If the pots are lightly perforated with even as few as
5-6 small slits near the bottom, the root system grows and thrives
all the way to the bottom of the pot ... all through our eight
month long growing season. The resultant growth of the waterlily
is thus greatly enhanced throughout the entire season. These
perforations allow passage of oxygenated water into and out of
the root zone at the bottom of the pot, preventing anaerobic
The slits in my pots are only one inch (2.5 cm)long, and
tight enough that no soil comes out. (I stab each pot a few times
with a sharp steak knife!) Root systems of tropical waterlilies
are so vigorous in perforated pots that, half way through the
season, we often need to do a "chop and drop" on our
display plants ... unpotting them, chopping off the bottom 3-4
inches (7-10 cm) of root ball, and dropping them back into the
pot with more soil, so their crowns are once more even with the
I do not doubt that some aquatics will do well growing
deep into anaerobic Soil ... the lotus is one that comes to mind.
But my belief is that the top few inches of soil in a pond (or
in a pot) are able to have enough water exchange, along with
the accompanying oxygen, that this top layer is fairly aerobic,
rather than anaerobic. It has also become clear to me that by
preventing anaerobic conditions in the growing pot, tropical
waterlilies grow faster, larger, and later into the season.
Having now aired my observations...I hope y'all start perforating
Good aerobic exercise, if you have a few hundred to do!
Dan Robinson, Texas USA, added these questions: At one
time did the pond support plant growth? What was the source of
the EPDM liner? Not all EPDM "liners" are pond safe.
Sometimes roofing liners are substituted and may have coatings
that may be toxic to plants/fish.
Marian Ritchie, Texas USA, offered this comment: What about
the gravel you used. Where did it come from and so forth? Do
you ever fertilize the plants? I think the answer is going to
be that something simple is out of whack. Sometimes we just over
think everything! Good Luck and I hope you can solve this problem
soon. Happy water gardening.
Dan Robinson weighed in again with this tongue-in-cheek solution:
Forget growing plants. Bottle the water and sell it to aquarium
shops as an algaecide.
Canadian pond professional Jeannie Suffern had this to say:
On a general note, we have found in Alberta, [Canada] that
aquatic plants do not do well in ponds filled with well water,
especially if there is a high content of sodium, soda and sulphur.
The hyacinths are usually the first plants to die off.
Some further discussion was taking place simultaneously on
the CAC Message Board.
A couple highlights from the message board:
From Cliff Motel McCready [dont even ask]:
Lots of good information here. My initial reaction was salt
intrusion without even reviewing the lab analysis. AJ made the
point very clear to me when he mentioned the high levels of sulfate,
calcium, and magnesium (all found in salt contaminated wells).
We had a pond in Foley, Alabama USA, (12 miles from the Gulf
of Mexico) a few years back in which EVERY aquatic plant we installed
died within a week with the exception of the cattails. (They
were stunted also.)
What is the fish load like? I believe the only realistic
solution for this large of a pond is to over load with "large"
fish and monitor the nitrate levels and check salinity frequently
during peak growing times (late spring and summer).
Also: How deep is the well??????
From B.J. Linger, CAC in New Jersey USA: Hey Mike, not
that it helps ... but ... when I was there with you in the winter
a couple of years ago ... I distinctly remember a white salt
line on the rocks around the edges!
Jim Purcell of Oregon Aquatics finally commented privately
with these insights which I felt presumptively free to share
in this article:
Interesting. The consensus seems to be that there are too
many mineral salts, and probably in the wrong proportions as
well. Using the water to spray and water pots of terrestrial
plants is a good idea; putting plants side by side in tubs using
different waters is even better, but more work.
One thing I was thinking they should do is test the wells separately.
If the water from one tests out a lot better than the other,
they could perhaps use only one well.
If it is salt water and they cant get rid of it, salt tolerant
estuary type plants may be the best option. It is very limiting,
but you deal the cards you are given. Maybe some mangrove species
will grow there -- that would be cool.
Also, while it is possible that the ------ and ------ fried from
overheating in transport, it is not a forgone conclusion by any
means, and I would not rule out the water for them, either. If
they were on their way out from shipping, there should have been
some indication of that when the box was opened. As suggested,
they would be perfect candidates for comparative water source
studies, as they are easy to handle and react quickly.
Dennis and Luana Mitchell, Wailuku, Hawaii USA, had these
questions to add to the mix too:
What an interesting situation. We've seen ponds similar to this
here on Maui. Plants just don't grow. They don't die within 8
hours, but they never last more than a month.
1. Are there fish in this pond? Are they ok?
2. What is the dissolved oxygen?
3. Is there algae in the pond? What type(s)?
4. Has the pond been tested for copper levels?
5. This is a liner pond, correct?
6. Are you sure everyone is telling the truth? (There's always
somebody in the mix who's not being completely forthcoming with
the total truth.)
7. What trees surround the pond? They are not eucalyptus trees
Somehow, and I don't know exactly what's going on chemically
but these ponds can usually be improved with MASSIVE aeration.
And oddly, it only needs it for 6 months to a year.
Keep us all posted!
Dennis and Luana
AJ Hicks again:
From this, I fall back on my bet-hedging consisting of
"The only other way would be some sort of drilling
thing, i.e. some drilling rig hit a salt dome and there was groundwater
intrusion which has spilled over into the wells."
I hail from natural gas country in western Pennsylvania,
where the natural gas frequently comes "brine," a salty
solution that must be captured and disposed of properly. The
brine contains concentrations of heavy metals that are very nasty
-- mainly strontium and barium, IIRC, but there are certainly
others. These salts are left behind from the oceanic deposits
which form the shale layers, which then undergo post-depositional
changes that produce the hydrocarbons we value so highly, i.e.
natural gas and oil. These products are pumped together (hydrocarbons
+ brine), the brine set side for reinjection into other wells
that have usually been dead for many years, and the natural gas
and oil then go on to make valuable products like shiny plastic
If the brine is not captured, it ends up leaking into rivers
and streams -- hardly quite so much of a problem in west Texas
perhaps, but very serious in Pennsylvania. Some capture tanks
leak, and the salt water (being salty) leads deer to feed on
the water and salt crust that results, with predictable mortality
-- usually to deer that are in utero. I seem to recall barium
and (to a lesser degree) selenium are the problem species, although
it's now going on 15 years; the memory is hazy, and Google is
With this in mind, a repeat water test -- along with a
panel for heavy metals -- is recommended. Either the well has
tapped into marginally saline waters, or there is some oil/gas
drilling contamination or drainage or somesuch.
I would suggest the reason why the terrestrial plants are
doing OK is that the exchange capacity of the soils is, for the
time being, accommodating these element problems. If the area
is desert dust-to-lawn, the surface soils are probably reasonably
accepting of these ions, but their capacity will likely be met
at some point. From there, they too may succumb. The pond plants,
with a very low soil to water ratio, have met their match already.
While I am familiar with the area thanks to my time as
a grad student in geology and geochemistry at New Mexico Tech
(and as an occasional caver in southeast New Mexico which includes
that spectacular Permian reef with similar geology to Midland),
I have a friend who is a PhD in geochemistry who spends half
of his time in Carlsbad. I'll bounce the problem off of him.
Dennis and Luana completed the thread discussion with these
Hmmm ... It'll be interesting to see what the heavy metals
results are. I'm guessing there is copper in the water. Not enough
to hurt the fish, but enough to kill the plants. Very strange
indeed. And you're sure no one has used a chemical in the pond
at some point? How about spraying around the pond? (We had someone
spray Roundup on weeds surrounding his pond and it killed all
Our question about everyone being forthcoming with the
truth was directed more towards the property owner/caretaker.
Usually contractors are very open, but we've had some troubles
with homeowners/caretakers NOT being so honest. For example:
homeowner says -- "My pond is constantly green and smells.
It must be all YOUR fault! You have to come out to my house and
clean my pond for FREE!" We go out there and see that the
homeowner failed to tell us they have a HUGE flock of ducks!
Best of luck! This is a tricky one. Just remember... usually
the simplest answer is the correct one.
Dennis & Luana
After distilling all the advice from the folks at V-A with
what we already knew, my recommendation to Michael was this:
OK ... after hearing all the ideas from some very informed
folks, here are my recommendations:
A) Repeat the water tests and include salinity, heavy metals,
B) Taste the water ... hey ... you're a CAC!
C) Forward the test results, assuming the new ones are consistent
with the previous ones -- to the local extension agent and have
him come out there if he will. This is a free resource so why
When we nail this down I'd like to post the results on
the WGI/VA thread so everyone who helped us out can get closure
as this is a rather unique situation.
Michael has agreed to follow these recommendations but we
do not yet have the results of the retesting and additional tests.
Kit and I thought it would be fun to let the WGI/V-A members
review all the evidence ... then offer an opinion before the
results are in. Its also quite possible that the results
of these final tests will not be conclusive, and we may not have
definitive closure even then. Well thats how real life
is sometimes ... inconclusive.
Regardless of the ultimate outcome, this problem with aquatic
plants in Texas simply serves to illustrate to what a wonderfully
diverse and caring international pond community we all belong.
Its been a real pleasure participating in this exercise!
As soon as all the test results are in, theyll be posted
and published. In the meantime ... what do YOU think is the problem
with this pond??