The Samaan Grove Wetland System

Wetland Inhabitants - Plants
by Kevin Kenny - Click images to enlarge

Bog Plants

The bog plants of Samaan Grove are diverse and are meant to clean surface water runoff. We also wanted to create a water garden that would improve land values and foster a good relationship between the residents and the natural environment. The following is a brief description of the plants you will find at Samaan Grove as of the date of this report. We will continue to search for other plants that are attractive and improve the effectiveness of the wetland system. We may also eliminate some species which become too difficult to handle.

Rushes, Sedges. Throughout the length and breath of the island you will see rushes growing in conditions ranging from damp soil to drains with water depths of up to .5 meters (1.5 feet). They are very aggressive and will dominate any area. The only time we ever saw them recede was at the first wetland SWW#5, where the local rabbit grass dominated and eventually smothered the rushes. These grass-like plants of the Cyperaceae are better known by their more common name, sedges. Creeping rhizomes, three-sided stalks and an inflorescence composed of a series of scales (each one subtending an individual flower) characterize them.  

Corkscrew rush, Juncus effusus spiralis. We imported seeds from the US and gave them to Peter Moll at the San Antonio Nursery, Port of Spain, Trinidad, to propagate. It turned out to be one of the easier of the imported plants to grow from seed.

Juncus effusus spiralis >

Local rush

Cattail, Typha latifolia. We have not yet introduced cattails to the wetlands because of their very aggressive nature. We plan to do so as the bog areas develop. They will grow in water depths of up to .3 metres (1 foot). Cattails produce extensive fleshy rhizomes, with stems growing to 2.7 metres (9 feet). They provide an excellent breeding habitat for many water fowl and cover for the more shy species.
Swamp fern, Acrostichum aureum, grows all over Trinidad and Tobago. Plants appeared naturally and were not transplanted. They exist in the wetlands at Buccoo, Pigeon Point and at Tobago Plantations.  

  American lotus, Nelumbo lutea. These plants were grown from seeds purchased on EBay. At first we had great difficulty getting the plants to grow. They developed a white fungus which enveloped the seed, eventually causing the new roots and stems to rot. We overcame this problem with regular water changes and were able to get a number of full sized plants.
They were transported to Tobago and placed in the lake at Petit Trou Point at Tobago Plantations awaiting the completion of the lakes at Samaan Grove. We were delayed in getting the Samaan Grove ponds finished on time, and the plants eventually grew out of their pots and spread all over the deeper areas of the holding pond. At different times of the year we noticed a die-off of the leaves which, when first observed, caused us some concern. Within a month or two they would spring back to life, growing new leaves all over the pond.

Lotus at Petit Trou Point, Tobago Plantations
This new growth corresponded to the periods when there was a flow of fresh water entering the pond at the start of the rainy season. It has taken some time for the aerial leaves to develop as the waterlilies and rushes at the edge of this pond kept them in the deeper water. Eventually we were able to retrieve some tubers from the edge of the pond. We transplanted them into a pot in the Tobago office pond P-24 where they have done very well. We plan to introduce these plants next year in SWW#6.  

Purple Pickerel Rush, Pontederia cordata. We got these Pontederias from Peter Moll. The photograph at the right, taken in May 2004, shows the preparation of the area where we planned to place these wonderful bog plants. We added 15 centimetres (6 inches) of top soil to the clay pond liner to provide a good substrate for them to grow in. We chose to plant them right at the edge of the shelf as we were uncertain they would survive when not immersed. We placed 12 plants approximately 1 metre (3 feet) apart allowing room for them to develop and spread. 

< Flowering

The plants seem to love the conditions as can be seen in the picture below right taken in January 2006, eight months after planting. At the end of dry season in May 2006, when the water was at its lowest, we were pleased to see that they continued to do well.

The first planting on the edge of the shelf at SWW#6

January 2006
This shelf area dries out in the dry season with the pond dropping about .5 meters (1.5 feet), exposing parts of the shelf. What is especially good about these plants is that they make excellent habitat for the water fowl. Both common gallinule and black-bellied tree ducks have been seen with young in this area although no actual nests have yet been found. 

May 2006 at the end of the dry season
You can see the waterline clearly marked on the plants.

Pink Pickerel Rush, Pontederia cordata pink form, has not done as well. The 12 plants we received were placed east of the purple in similar conditions. Perhaps because of their smaller size they seem to have problems with the water depth. We have since transferred some of them to shallower water to see if their growth rate improves. The picture on the right shows when they were first planted. After we started to lose some of the plants we transplanted one into a container at the office and it has done quite well. 

What is of interest is that when we transplanted both the purple and pink into the same container. The purple quickly dominated the space, forcing us to remove it and place it in a separate container. Once this was done the growth rate of the pink improved and the plant seemed less stressed. This may also be the reason that the pink did not do well in the pond. In order to help them through their first season we placed two pond tabs next to each of the plants regularly to give them a boost, after which they were left to fend for themselves.

Black taro and our white night blooming waterlily
Black taro, Colocasia sp. Many people in Trinidad and Tobago do not realize that this plant loves wet soil and will thrive at the edges of ponds and water courses. It was originally imported from Hawaii and has become a very popular local horticultural plant.
The local green variety of Xanthosoma is used to make a delicious soup called "cal la loo". Green taro (the dasheen plant) existed naturally in the drains that ran through the estate and did not take long to establish itself along the edges of some of the ponds.
We tried to transplant some in SWW#6 but they died when the area was flooded. Both black and green varieties like wet soil but do not seem to do well if their roots are continuously covered with water. They grow in a vide variety of soil conditions.  

. Local green taro in SWW#6 did not survive.

Iris, Neomarica longifolia and Iris sp. The local yellow or walking iris (Neomarica longifolia) is not a natural water iris but will grow in moist soil. We planted over 100 of these in various places and soil conditions, but they did not do very well. To solve this problem we imported a mix of water Iris seeds from the US which were given to Peter Moll to propagate. Although half of them have since sprouted we have not yet transplanted them.

Irises' exotic flowers have an obvious appeal and their roots are useful as filtering agents, which is why we have targeted them. Louisiana Iris can be planted along the edge of ponds or directly in shallow water. We have great hopes for these plants and feel that, once acclimatized, they will compete with the Nariva red night blooming waterlily as one of the signature plants in the wetland.  


Canna, Canna glauca. This plant likes wet soil and the common yellow variety can be found growing in drains and ditches of both islands in water depths of up to 12 centimeters (5 inches). We were able to get a red hybrid, below, which seems to like similar conditions.

The yellow variety grows well at the edges of all the lakes but does not spread into the deeper water. It grows in different parts of the estate in very dry soil but we suspect that the roots have grown down to the water table.  

Red hybrid v | Local yellow Canna >



Initial planting in November 2004
Papyrus, Cyperus papyrus. Giant Papyrus, which is not native to the islands, was found growing at the Caroni Swamp in Trinidad, where we obtained a number of rhizomes. They were first planted at Petit Trou Pond but did not do very well. We transplanted them into the first wetland SWW#5 where they thrive.

Six months later they had grown into robust plants. Today, some two years later, we have to cut them back to ensure they do not dominate the entire wetland area.   
This plant grows to 3 metres (9 feet) in height. It will also grow in conditions varying from direct sun to partial shade. Cut leaves that were allowed to float free have since formed plants in other parts of the wetland. 

Waterlily, Nymphaea

Trinidad and Tobago have a number of local waterlilies that can be found throughout the islands. Visiting Nariva Swamp some years ago, we were surprised to see the abundance of lilies in the area.

Local copper vessel at the entrance to Samaan Grove
We arranged for our landscaper to make a trip to Nariva where he purchased a number of plants from the local residents. The people who live and farm in the area are very poor and he was received quite warmly. No one had ever offered to pay for the plants that grew in the drains outside their houses. By the end of the day they gave him all he could carry for $30.00 US.

Night Blooming Waterlilies

White (probably Nymphaea lotus). The first time we saw this plant in bloom, it was early morning and we thought someone had thrown garbage all over the Nariva wetland. We were amazed when they turned out to be flowers. They open at night around 7:00 pm and stay open until the following morning around 10:00 am when the day starts getting hot. They like plenty of nutrients and grow to enormous size when fed with pond tabs in our wetlands. They also reproduce at a great rate. We had only one plant in Pond 6, and a year later had over twenty large specimens. These all grew naturally from seeds and now provide us with an abundant local supply.

Red (possibly a form of N. lotus). Like the white, the flower opens early in the evening and will stay open until the following morning. It grows from tuber and is easy to propagate. When my staff brought a number of large plants from Trinidad, we had a great deal of difficulty preventing them from floating up. Eventually we devised a system using bent rebar to hold the plants underwater until the roots took hold. During that time a number of them still managed to float.

To our amazement we realized that each root stock was made up of multitudes of small root balls that could be broken off from the main plant. We were able to get about 50 plants from the first large root ball which we planted at the edge of the lakes. In a few months we had massive plants with leaves measuring over 50 centimetres (20 inches) in diameter. We got this growth because we supplemented each plant with pond tabs. It was amazing to see the effectiveness of these great fertilizer tablets. Once the plants settled we decided to discontinue the use of the tablets to see how they would acclimatize in their new conditions. Not surprisingly there was a die-off in the following year. These ponds are lined with clay which has very little natural nutrient. The plants flourished in places where fresh water enters the pond, bringing with it new silt that contained nutrients.

This has proven to be one of the easiest plants to propagate by simply planting these root balls anywhere we want a lily to grow. In fact we had so many root balls we started throwing them in different parts of the lakes. Not surprisingly they established everywhere we threw them.

We call Lake 1 Red Lake because of
the number of red waterlilies that
grow on its edges. (We may have to rethink this name as it is proving
difficult to keep other lilies out
of the lake.)


Pink (possibly a form of N. lotus or a natural hybrid between the white and red). We had heard about the pink night bloomer when we first visited Nariva, but were only able to get two plants. We lost one in the last dry season when the shelf dried up. We had hoped that its root was buried deep enough for it to survive but it has not reappeared. We transplanted the surviving plant to deeper water before the end of the rainy season.


Day Blooming Waterlilies

Tobago white (possibly N. pulchella). This lily can be found throughout Trinidad and Tobago. It is of particular interest to this project as it was found growing profusely in the Buccoo marsh pools. During the dry season these ponds completely dry up and in some cases are burnt by seasonal fires that scorch the area. Almost as soon as the water returns in the rainy season the plants spring to life and within a few weeks cover the shallow ponds.


La Brea Blue (possibly N. capensis).
  This lily was found at the Pitch Lake in south Trinidad. We were able to retrieve two plants which were placed in Lake 2A. The flowers are still quite small, about one-fourth their regular size as seen in Trinidad. We hope to add many other coloured waterlilies to the lake which we plan to call "Carnival".


Nymphaea mexicana.

We have kept this lily in containers because of the reputation it has for taking over and displacing other aquatic plants. It will be introduced in an area where it can be contained and if necessary eliminated.  

Victoria amazonica


Without a doubt the queen of the water plants at Samaan Grove is Victoria amazonica. It took many years of research to track down a source of supply. The first plant was imported from a nursery in the US and arrived via air freight in good shape. However, our plant quarantine division did not accept the documentation supplied and had the plant dipped in an insecticide which dissolved it instantly.

Eventually our internet searches turned up the Victoria-Adventure web site and we were able to source seeds from Kit and Ben Knotts in Cocoa Beach, Florida. Kit took the time to teach us how to propagate this wonderful species and we have been friends ever since. There were many challenges in getting Victoria to grow but we did eventually succeed.


Perhaps the most painful experience we had was when someone attempted to steal the fully grown plants that had been transferred to Samaan Grove resulting in their destruction.

These magnificent lilies flower almost every night. The flowers are coloured white on the first night, turning dark pink the following night, before dying back to become a seed pod. To date only one of these seeds has sprouted naturally and we were unable to grow this plant to maturity. We are sure that over time we will see many new plants emerging from the ponds in the places where these plants first grew and flowered.  


< ^ Our aquarium setup where
we grow the plants from seed

Floating Plants

The only one of the many floating plants available to us that is being considered at Samaan Grove is water poppy (Hydrocleys nymphoides), which grows in the Nariva Swamp. It will survive in water depths of up to 40 centimetres (16 inches) deep but prefers shallow conditions with depths of 10 to 15 centimetres (4 to 6 inches). It likes rich topsoil which would indicate that it should do well on the shelf at SWW#6.

The photo at the right was taken at Nariva and shows the plant only growing at the side of the wetland. We plan to introduce this plant after the shelf has matured.

Submersed Plants

One of our main plans for all the lakes and ponds built has been to have the sides and bottoms entirely covered in submersed plants. This would help keep the lakes clear by preventing the soil from suspending in the water. The five types of plants we are experimenting with are tape or eel grass (Vallisneria americana), Sagittaria subulata, Amazon sword plant (Echinodorus amazonicus), hair grass (Eleochariss acicularis) and various types of Cryptocoryne

Vallisneria americana. The one grass that has done very well is Vallisneria. It was placed in SWW#6 which receives runoff from Lake1B. It took a good six months for the plants to establish. Once the rains arrived in June 2006, growth of this grass exploded and has almost covered the entire bottom of this pond.

^ v Vallisneria americana

One of the main problems we encountered in the early days was the appetite of the ramshorn snails that seem to feast on the young leaves. It took a few attempts and a large number of individual plantings for the grasses to grow faster than the snails' ability to consume them. Once the first plants colonized they spread around the edges of the wetland pond. What continues to limit the growth down to the very bottom is the lack of clarity of the water, limiting sun to the underwater leaves. 

Sagittaria subulata. This is one of our favourite underwater aquarium plants but has proven difficult to grow at Samaan Grove. We placed a number of young plants in three separate ponds with little early success. It is difficult to say what conditions impeded their growth.

Sagittaria subulata
We have since planted it in the new lake in Samaan II along with the Amazon sword plant and the results have been encouraging. Ribbon shaped leaves grow up to 24 centimetres (9.5 inches) long and may be as much as 1.5 centimetres (.6 inches) wide. The plant reproduces by runners and is already forming dense colonies on the sides of the lake which help to stabilize the soil.   

Cryptocoryne. We have also been planting Cryptocoryne in all the lakes and ponds with little success to date. These plants were received from Peter Moll who had imported them to sell to the aquarium trade. He gave us two batches, one of which was planted at Samaan Grove while the other was kept in an aquarium. Most crypts do not like a lot of light and prefer clear water. They will also grow in moist soil so it is difficult to understand why we have not had better results.

Amazon Sword Plant, Echinodorus amazonicus. So far we have had tentative success with Amazon sword plants. The submersed leaves seem to hold silt and have not grown well. We transplanted them in Lake 0 and are now starting to see better results.  

Hair grass, Eleocharis acicularis. On a visit to the Nariva Swamp in 2002, we had lunch at one of the villager's homes and were fascinated by a pond in his back yard. The pond was completely covered with hair grass seen in the photo below left. He claimed that it was filled with only rain water which was the reason it remained so clear and clean. Ten feet away there was a much larger pond and the water clarity was terrible. In our opinion it was the hair grass that produced the different result.

To commercial lake managers, the genus Eleocharis should be avoided. Most of the species are problematic weeds that clog waterways. We plan to use this grass at the very end of the wetland system just before the fresh water enters the sea. This is where it grows in Trinidad. We have never seen it growing in Tobago.

Eleocharis acicularis ^ >

Moisture Loving Plants

Heliconia. We introduced a number of Heliconias as background plants in many of the wetlands. They seem to grow well in moist soil conditions and provide excellent habitat for wildlife. We are still experimenting with different varieties.

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