My Green Wet Thumb: Sublime Sagittaria Derek P.S. Tustin

Last summer was an interesting one for me. As I’ve both aquarium and bog plants, and equally obvious that written here, I expanded into the world of pond gardening. they have been used in aquariums for about as long as One of the most interesting things to me during my set-up there have been aquariums. But this ease of growth has of the tub and later the pond, was how many plants were also lead to them being a problem. Various species actually suitable for both an aquarium, and for a pond. have been labeled as noxious weeds in several US However, of all the plants that I tried, the one that states, are banned entirely in the Australian state of captured my interest the most, and the one I have found Tasmania, and have become a weed in irrigation myself thinking about and planning for next year, are the systems and drains for crops such as rich in 50 plants in the Sagittaria genus. countries.

In the past I have had Sagittaria plants (“sags” as they are The genus name of these plants, Sagittaria, is derived commonly known) in my aquariums. The extent of my from the descriptive word for the shape of the leaves, knowledge was that they were similar in appearance to “sagittate”, which means “arrow-shaped”. They are part plants from the Vallisneria genus (“vals”), and that the way of the Alistamaceae family, the water plantain family that to tell them apart was that vals had a serrated edge that also includes the swordplants of the Echinodorus genus. you could feel if you ran your finger along the edge, and Another point of interest is that Sagittaria can absorb that sags did not. large amounts of toxic metals from their environment, which makes them very useful in soil remediation. But as I tend to do when something captures my interest, I began researching the Sagittaria genus of plants, and was Usually when I write about a genus of plants, I try and even more intrigued. I can’t wait for spring to arrive and give some broad descriptions of the various plants in the for my pond to start up again. Rest assured, I plan on genus. However, with the Sagittaria genus, it is very having a variety of sags in my outdoor garden next year. difficult to do. Some grow small (Sagittaria natans or dwarf sag with mature leaves as small as 5 centimeters Most of you who keep plants only in aquariums will know or 2 inches), while other grow extremely large (Sagittaria these plants as sags. However, if you keep them only in montivedensis or the giant or Aztec sag, with leaves ponds (or ponds as well), you will probably know them growing in excess of 80 cm or 32”). But even with these better as arrowheads. But if you lived in western North wide variations, there are many similarities amongst all America a couple of hundred years ago, you would have plants in the genus. known them as “Wapato”. Wapato was the word in the Chinook Jargon trade language for what later came to be There are usually two types of leaves possible. The first known as “duck potato” or “Indian potato”. (Just to fulfill are submerged leaves. They are strap shaped, very similar to Vallisneria leaves. It is possible to only have you educational quota for the day – Chinook Jargon was a pidgin trade language used along the western coast of Sagittaria produce submersed leaves by pruning leaves North America, roughly from California to the Alaskan that reach the surface. The second type of leaves are panhandle, in the late 1700’s / early 1800’s. It was made emergent, and usually shaped like an arrow, hence one from the co-mingling of words from various indigenous of their common names. They often reproduce by native languages, as well as French and English. It was runners, and usually have fleshy creeping roots know as rhizomes. Flowers, which will only grow if the emergent not a Native American language.) type leaves are formed, will always be lower that the leaf Apparently the tubers from various species, most height. The flowers will be either white or sometimes specifically Sagittaria latifolia, were the prime starchy food pink, about 3 cm (1”) in diameter, are formed in in the historical diets of Native American, Central groupings of three at the end of the flower stem. If American and Asia populations. With the introduction of successfully fertilized, the flowers will produce clusters of the potato (Solanum brevicaule) from Peru in the 18th what are known as “fruitlets”, which contain oblong century, the popularity and use of the “duck potato” seeds. The seeds float very easily and in nature can be declined, but it is still eaten in Asia and Hawaii. When carried long distances, where they eventually sink and steamed or roasted, the tubers are reported to have a start the cycle over. sweet and nutty taste. (Educational Interlude #2 – Did you know that the potato we eat today is actually from They prefer silt or clay mud (with organic soils not being Chile, is scientifically known as Solanum tuberosum recommended) and shallow water. When grown in a tuberosum, and is not the same potato, Solanum pond, they should have a sunny or partially shaded brevicaule, that was initially introduced? Well now you position at the edge of the pond, with a water depth of no do!) greater than 30 cm (12”).

So with the long history of being used as a food source, it One of the greatest problems with the Sagittaria genus is the extreme confusion surrounding the proper naming of should be evident that these plants are easy to grow as (continued on page 16)

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My Green Wet Thumb: Sublime Sagittaria (continued from page 8)

these plants. This past summer I purchased a plant water should also be 15 cm (6”) above the crown of the identified as Sagittaria lorata. It did extremely well in my plant. Male flowers are usually found on the lower part of pond, even flowering and I submitted it to the Aquatic the flower stem, and female flowers on the top, but they Horticulturist Awards Program (AHAP). However, while can sometimes be mixed. It can be found across Canada, researching this article, I discovered that Sagittaria lorata but is rarer in Alberta and more common in British is actually another name for Sagittaria subulata, a plant Columbia. that I had already submitted for points. (Oh, to be honest and fair, I am publically asking our esteemed AHAP chair, Sagittaria natans – Dwarf Sagittaria Paul McIntosh to rescind my points for S. lorata. However, Native to the Atlantic coast of North America (from Maine it did flower, so if you could apply the flowering to S. to Florida), it usually only grows submerged. The leaves subulata, I would be appreciative.) Following this article are dark green and grass like with a rounded tip. The you will find a chart detailing what I have been able to leaves range from 5 cm (2”) to 30 cm (12”) in height. If the discover regarding valid types of Sagittaria, the various water is too shallow, leaves will tend to float on the surface sub-species, and the incorrect synonyms that some plants rather than growing emersed. White flowers may form and may be known under. Should you be interested in they will float on the surface rather than growing emersed. propagating or submitting species of Sagittaria for AHAP It is considered to be a hardy form of the Sagittaria genus. points, this chart should be of some assistance. Sagittaria graminea – Narrow-Leafed Arrowhead Many of the plants on that list are locally unavailable, but Native to the eastern half of North America (as far west as occasionally you can obtain some locally. Here are Wyoming and from Labrador to Cuba in the east), it has several that are commonly available: also become established as a noxious week in Australia. It grows in water up to 200 cm (80”), but will only form Sagittaria sagittifolia – Common Arrowhead emersed leaves if grown in water less than 50 cm (20”). Native to both Europe and Asia, it produces previously Flowers are white (occasionally pink) and form 2 to 12 mentioned tubers that are still eaten in Asia and Hawaii. three-flowered groups on the flower stems. There is a The leaves can be up to 45 cm (18”) long, and produces particularly sought after variation, Sagittaria graminea white flowers. There is also an interesting variation called ‘crushed ice’, that has green leaves variegated with Sagittaria sagittifolia ‘flore peno’. The flowers are creamy white stripes. Saggitaria graminea is considered considered to be “double-flowered”, look like puff balls, to be a hard example of Sagittaria. and bloom for a longer period than the regular flowers. The water should be 15 cm (6”) above the crown of the As you can see, there are many varieties of Sagittaria plant. It is considered to be a hardy plant. available. Whether you be growing them in an aquarium, or in a pond, these plants are unique and beautiful. Sagittaria montevidensis – Giant or Aztec Arrowhead Native to South America, it grows to more than 80 cm or Sample Species Profile 32” in height. Flowers are produced in clusters at the end of the stems, and will be produced all year. The flowers Latin Name: Sagittaria sagittifolia are white, each with a dot of crimson at the base. It is a Common Name(s): Common Arrowhead short-lived perennial (a perennial being a plant that lives Height: 30 – 45 cm (12” – 18”) two years or more), but it provides an abundance of Width: 10 – 15 cm (4” – 6”) seeds. In our area, it can be wintered indoors where it will Light: low - high o o o o go into dormancy through the winter. It is considered to be Temperature: 16 C – 28 C (61 F – 83 F) a tender plant. PH: 6.0 – 9.0 Hardness: slightly hard – moderately hard Sagittaria lancifolia – Lance-Leaved Arrowhead or Growth: fast Bulltongue Arrowhead Difficulty easy Found in the Southeastern United States, especially in the Origins: North America, South America Everglades, it is also found in South America. The leaves, and Asia which can grow to 80 cm (32”) in height, are more spear Source: Various than arrow shaped and are dark green in colour. The flowers are white with a yellow centre. A variation, Sagittaria lancifolia ‘rubrum’, has red stems. It is considered to be a tender plant.

Sagittaria latifolia – Duck Potato The plant described above that was used by Native American populations as part of their diet. It can grow up to 90 cm (48”) in height, and produces the mentioned tubers at the end of its roots. The tubers can be detached and eaten, or detached a planted. The surface of the

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