Category: Plants

How to keep, grow and propagate plants.

Water Plants for Ponds and Bogs

When we think of a backyard pond the first few images that pop into most of our minds are those of fountains and fish, usually a goldfish. I think these images must come from viewing too many water features in restaurants, garden centers, and public gardens. We also visualize their bottoms covered with copper pennies, nickels, dimes and assorted small pebbles and toys. These same ponds are also surrounded by potted tropical plants and some even have fake plastic plants “growing” out of the water. But I think we can do much better and create a pond that comes much closer to nature.

Plants that grow in water come in all sorts of shapes and sizes. Many of them flower and most produce interesting leaf shapes. Recently the gardening world has seen huge growth in the popularity of water features from tiny tabletop fountains to very large backyard ponds. The overall benefit from this interest is the increased availability of products: in equipment, hardware, plants, fish, and ornaments, there is an almost overwhelming choice. The problem gets bigger when we have to try and decide what kind of water feature we want to construct: Small? Large? Fish? Plants? I know some people who just gave up, bought a book, and just looked at the pictures. Some even put the scanned pictures on their computer as wallpaper.

My focus in this essay isn’t on the actual pond or the fish but on what you can put in your pond that takes little care, no daily feeding, and provides an summer’s worth of interest. These are water plants, and I confess absolutely my most favorite part of a pond.

Water plants can be divided into many different groups based on their characteristics; my two basic groups are: hardy (meaning they will live through our winter) and not hardy. The “not hardy”s include all tropical/exotic water plants, all annual water plants, and what I call the iffies.

But probably the most useful way to group water plants is by water depth, or how much water they will tolerate above their crowns (the growing point where the leaves emerge). These groups are:

Submerged: plants that grow below the surface of the water, and can be rooted or free floating. Sometimes called oxygenators; e.g. hornwort

Floating: free floating plants who’s leaves rest on the surface of the water and who’s roots hang in the water column; e.g. duckweed.

Rooted Floating Leaf: rooted plants (deep or shallow) whose leaves float on the surface of the water; e.g. water lily

Emergent: rooted plants with crowns above the water surface and leaves that don’t float; e.g. bulrushes

Marginal: plants that grow at the pond edge in wet boggy soil and can tolerate some water over their crowns during the spring; e.g. marsh marigold

Before going to a greenhouse be sure to have the following questions settled in your mind, there is nothing worse than coming home with more plants than water and having to frantically dig more ponds or run to Home Depot to clean them out of rubbermaid containers.

How big is my pond? Is it a small rubbermaid container (or in my case several cat pans), a deck sized ½ whiskey barrel, a preformed drop in pool with narrow plant ledges, or a large lined pond with lots of room?

Is it located in the full sun or shade?

Are there fish? Minnows, goldfish, or koi?

Is there still water or moving? Fountain or circulated?

Be aware of the following: fish like to eat plants. Koi in particular will demolish plants: potted ones are their favorites. Fish also need cool water for oxygen levels to remain safe, while water lilies like very still and warm water. Warmth, sunlight, and fish poop make for great algae growth, especially hair algae (the bane of most ponders). Consider also that a pond without at least some fish will be a haven for mosquitoes

Here is a list of some water plants I grow. Not all of them are hardy or native but are instead just plain fun to have for flowers or interesting leaves.


Hornwort (Ceraphyllum demersum): not rooted. Look for nice green, loose bunches, any with brown stems are dying and bunches with very tightly held leaves never seem to survive long after being bought. I think this has something to do with what stage of cold dormancy they are experiencing. Not winter hardy if frozen solid.

Canadian Pondweed (Elodea canadensis): best if rooted. Great for ponds without koi, or better yet in a phytofilter (a plant filled pond used as a natural filter). Native, but not winter hardy if frozen solid.

Bladderwort (Utricularia vulgaris): rooted or not. Sends nice yellow snapdragon like flowers above water surface. It is carnivorous, as the little bladder parts eat infusoria, Daphnia, and fry. Native and winter hardy.


Duckweed (Lemna minor): a necessary evil, provides food for koi, shade at the surface of the pond (less algae), lessens water evaporation, and sucks up nutrients. Native and hardy

Ivy-leaved duck weed (Lemna trisulca): free floating delicate duckweed. Native and hardy.

Azolla (Azolla caroliniana): same as duckweed, but it’s a fern, and not native and not hardy.

Frogbit (Limnobium spongia): a nice free floating or partly rooted plant. Same usefulness as duckweed, but sometimes has tiny bottlebrush white flowers. Make great landing places for bees, dragonflies, and other critters. Not native and not hardy.

Water Lettuce (Pistia stratiodes): make nice velvety green clumps of leaves like floating butter lettuce. Sometimes has tiny white flowers. Needs warm water. Hates cold. Sucks up lots of nutrients. Not native and not hardy.

Water Hyacinth (Eichornia crassipes): beautiful clumps of dark green leaves, wonderful lilac flowers. Temperamental: likes full sun and very warm quiet water to bloom. Removes lots of nutrients from the water. Not native and not hardy.

Rooted Floating Leaf

Water Lilies (Nuphar sp): one of the most desirable pond plants. All hardy ones must have their root stock protected from freezing either in a deep water pond or wrapped in peat moss in the fridge, or placed in a very cool part of the basement/heated garage in a bucket of water. I have one and am hoping it survived the latest over wintering in the fridge. Its best to consult a specialist nursery for advice as to good local choices (Bearberry Creek Water Gardens, Sundre, Alberta 403-638-4231)

Yellow Water Crowfoot (Ranunculus gmelinii): nice little plant with yellow buttercup flowers. Sometimes over winters, native, but only iffy hardy.

Emergent and Marginal

It is very important to note what water depth these plants grow in. Some will tolerate a wide range of water over their crowns; while others will die if planted too deeply. For example, native mint: I killed it regularly when I permanently submerged the crown in as little as 1″ of water. The plant tolerates being submerged for a while but needs to spend most of its life in very wet soil or with its crown just above the water

Great Bullrush (Scirpus validus): a wonderful tall plant for water up to 4’ deep, dark blue green leaves 2’-7’ tall, clumps of brownish flowers in summer, native and hardy.

Common Cattail (Typha latifolia): lives in water 1’ to 2’ deep. A great plant for phytofilters. Needs a large pond if used as a decorative plant as it grows very tall and very fast. Be careful of the growth tips they are very sharp and strong and can puncture liner ponds. I have mine planted in a open sided container similar to a large milk crate lined with weed cloth. I can drag it out of the pond and divide it when necessary. Native and hardy.

Water Plantain (Alisma plantago-aquatica): another great native plant. Grows in 6″ deep water, has large wide decorative leaves. Sends up a tall 1’ spike of babies breath like flowers in the summer. Native and hardy.

Blue Flag (Iris versicolour): a water loving iris from eastern Canada. Grows in boggy soil and up to 2″ water. Produces beardless Siberian-iris style flowers in late spring. Easy to grow from seed. Many colors to choose from. Native and hardy.

Yellow Water Iris (Iris pseudacorus): taller than blue flag irises. Produces yellow or cream beardless flowers in late spring. Can tolerate slightly deeper water, up to 1’. There is a great stand of this iris in the Japanese section of the Devonian Botanical Gardens in Devon SE of Edmonton. Non-native (of European origin), but hardy

Water Sedge (Carex aquitilis): a nice grass like plant for pond margins. Tolerates 1″ water above its crown. To tell the difference between sedges and rushes remember this: sedges have edges, rushes are round; sedges have solid triangular stems and leaves that are flattened and also triangular, rush stems are round and hollow without joints like grasses; the leaves are round too. Native and hardy.

Knotted Rush (Juncus nodosus): thin round stems in a nice green color. The interesting little brown tufts in summer are the flower parts. Grows in 2″ water. Native and hardy.

*a note on rushes, sedges, and bog grasses: there are many species native to Alberta, but most are very hard to identify. I have a number of them growing in my ponds but I haven’t listed any more than the two above because I can’t be sure of their names.

Marsh Marigold (Caltha palustris): a bog plant that produces lots of bright yellow flowers in early spring. Single and double flowering cultivars are available. Keep crown above water level. Native to eastern Canada, hardy.

Arrow-leaved Coltsfoot (Petasites sagitattus): a bog plant with large downy silver leaves, flowers before leaves emerge. Native and hardy.

Palmate-leaved Coltsfoot (Petasites palmatus): same as above but with maple leaf shaped leaves really nice plant. Native and hardy

Wild Mint (Mentha arvensis): bog plant that has nice 6″ candelabra spires of tiny lilac flowers. The leaves have wonderful mint scent. Used as a medicinal plant by the Cree. Native and hardy.

Non-Hardy Ornamentals

The next few plants are just for fun in an outdoor pond. None are hardy over winter but some can be cultivated in an aquarium

Bacopa (Bacopa caroliniana): full sun, small blue flowers, grow partly submerged.

Umbrella Palm (Cyperus alterifolius): tall umbrella like leaves, sun to part shade submerge to 6″ or leave crown above water, fertilize regularly, snails can damage new growth.

Water canna: I haven’t tried this one but the flowers look nice.

Lobelia (Lobelia cardinalis): spikes with red tubular flowers, maroon leaves.

Monkey Flower (Mimulus guttatus): blooms with yellow snapdragon shaped flowers.

Houttuynia cordata variegata: striking red, green and cream leaves, white flowers in summer.

Variegated Pennywort (Hydrocotyle sibthorpioides): cream and green leaves.

Water Clover (Marsilea mutica): clover shaped leaves that will float on the surface

Jungle Val(Vallisneria americana): an aquarium plant that does very well in a pond, but remember to remove it well before winter.

You can also try putting other aquarium plants into a small pond. Or use a patio whisky barrel or other smaller container. You will see that many of our common aquarium plants will flower readily outside in the sun.

Plant Care

In nature water plants grow in a variety of soils, quite often they are clay based. I have found using very heavy soil causes anaerobic decay and often the plant dies. Using garden soil causes large outbreaks of algae especially hair algae. I now use a sand-based mixture formulated for pond plants that I found at a garden supply center. It is easy to mix up your own: use 50% quartz playground sand (3mm to 5mm) or sand blasting sand, 25% well rotted peat moss and 25% unscented pure clay based nonclumping cat litter. Mix up and use as needed. Don’t use dry or baled peat moss, but go to a landscape bulk supply center and bag up some heavy wet peat moss. If you have no choice take the dry stuff and pour lots of boiling water over it and leave it for a few days to soak. I pot almost all my plants in plastic-mesh aquatic pots. These pots have open lattice sides and bottoms. I line them with landscape fabric to stop the soil mixture from leaking out. After potting I push an aquatic plant tab fertilizer into the soil beside the plant, then top off the soil with some pea gravel to keep everything in place.


Bearberry Creek Water Garden Catalogue 2001, RR2 Sundre, Alberta Canada T0M 1X0

tel: 403-638-4231

Gadd B, Handbook of the Canadian Rockies, 1986 Corax Press

Johnson D, Kershaw L, MacKinnon A, Pojar J, Plants of the Western Boreal Forest and Aspen Parkland, 1995 Lone Press

Robinson P, Reader’s Digest Complete Guide to Water Gardening, 1997 Reader’s Digest Assoc

Wright, G, Alberta Water Gardening, 1999 Gary Wright

Water Garden Websites

Other Sources for Plants and More Information

Hawaiian Botanicals; 6011 No7 Rd, Richmond, BC, V6W 1E8; 604-270-7712 (water lilies and lotus)

Moore Water Gardens; Box 70, 4683 Sunset Rd, Port Stanley, Ont, N5L 1J4; 519-782-4052

Parkside Gardens; 251 Demetri Way, Saltspring Island, BC, V8K 1X3; 250-653-4917

Reimer Waterscapes; Box 34, Tillsonburg, Ont, N4G 4H3; 519-842-6049

Segger Koi Farm; 5371 Ross Rd, Abbotsford, BC; 604-857-7783

The Lily Pool; 33241 Pollock Rd, Keswick, Ont, L4P 3E9;905-476-7574

Water Arts Inc; 4158A Dundas St. W, Etobicoke, Ont M8X 1X3; 416-239-5345 ?

Tropical Plants in the Wild

Early this year I was able in observe tropical aquatic plants in their home environment and notice what the natural conditions are like. A big surprise to me was the environment I found some of these plants. Sure, the floating plants and marginal plants were on the side of rivers and ponds but there were some notable exceptions. The location was Costa Rica, home of incredible biodiversity: whether it be insects, plants, birds, or mammals, Costa Rica is right at the top with one of the highest number of species per area. But as for the aquatic plants, I really didn’t notice that many species because I was rather busy looking for birds.

The first surprise was an old familiar plant that I kept in one of my first tanks: this was Heteranthera reniformis. Looking nothing like its feathery cousin, the water stargrass (H. zosterifolia), this plant looks like a miniature water lily with hard, small, and round heart-shaped leaves. It grows in water-logged soil or very shallow water (as in long-term puddles) and also along the edges of streams. I found it growing on the sandy shallows of a stream that passes by the lava flow of the Arenal volcano. The remarkable thing wasn’t the plant itself but where it was growing. Arenal is an active volcano and the water temperature reaches 42C in some of the pools. With the exception of algae and this plant the stream was devoid of vegetation.

Beside the road, high in the Cordillera de Tilarán, I made two interesting discoveries. First, anywhere the soil was damp I found a type of pennywort (Hydrocotyle sp.). While we are used to seeing the aquatic species, this was most definitely a terrestrial form for the areas they frequented were not likely to flood. In fact under heavy rain the small ditches where they were would allow the water to flow very fast and carry a lot of sediment. The second discovery was an orchid, Sobralia powellii that grew profusely beside the road. I had never thought of orchids as ditch flowers!

On the Caribbean side I saw first hand the challenges that aquatic plants face in a forest environment. The frequent showers mean greatly fluctuating water levels. The forest canopy allows little light to reach the water and the fallen leaves stain the water dark, so the little light doesn’t penetrate far. I had seen black water streams before, but never ones so dark. I expected tea-colored water but in some places the water was as dark as Coke.

In the shallow streams the soil was clay with a thick layer of decomposing leaves, ideal habitat for Apistogramma and banjo catfish. The water here was very clear. In this setting I found, of all things, a water lily (Nymphaea sp.) with white flower buds.

In the larger streams the water was very muddy and I didn’t expect to see any submerged plants. Yet I saw pieces of what looked like Egeria densa close to shore. The shores themselves were mostly bordered by water hyacinth (Eichhornia crassipes) with a small species of Salvinia growing in the sheltered water between the plants. Flowers were not plentiful at the time and there were mats of these plants floating down the river. The largest mat was over three meters wide and contained grasses and a flowering creeper growing on top of the water hyacinth. Talk about biodiversity!

The final surprise came as a large patch of papyrus growing on a stretch of the river. The common papyrus (Cyperus papyrus) is an African plant, so what were these plants doing in Costa Rica? The family Cyperaceae has a worldwide distribution, so it is possible that these were of a Central American species. Another possibility, perish the thought, is that the plants are descendants of introduced ornamentals planted in someone’s garden. At any rate, they looked very out of place.

That’s pretty much all that I saw of aquatic plants. Considering that they were not the main focus of my trip I am very pleased to have seen them in a natural setting. I also learned to expect the unexpected.


Riehl, Rüdiger, and Baensch, Hans A. (1986). Aquarium Atlas. Melle, Germany: MERGUS-Verlag.

Riehl, Rüdiger, and Baensch, Hans A. (1993). Aquarium Atlas Volume 2. Melle, Germany: MERGUS-Verlag. ?

Aquatic Hanging Gardens

Ever noticed how nice a piece of driftwood covered in Java fern (Microsorium pteropus), or Java moss (Vesicularia dubyana) or even just plain algae looks? I call such pieces aquatic hanging gardens because the plants are not at the bottom as one would expect. This month I will cover how to make one of these gardens.

First let’s tackle the driftwood. Aquarium stores can provide driftwood of three types: mopani wood, mangrove root, and softwood attached to a slate. All three types are very convenient because they stay submerged, but they are not cheap.

Mopani wood is very dense, almost rock hard when dry and comes with two tones; a light beige and a contrasting very dark brown. It comes from Africa and sinks readily. I have never used it, so I can’t comment on its merits as a hanging garden platform. I would suspect plant roots would have difficulty attaching to mopani.

Mangrove root* is one of my favorites. It is hard, with a gnarled surface, very dark brown, splinters quite easily and sinks without having to be waterlogged. Its gnarled surface and the many cracks make it ideal for plants to anchor their roots (I even had a Hygrophila polysperma attach itself to a piece). The dark color contrasts well with the green from the aquatic plants.

The softwood attached to slate comes in many different sizes and shapes. They are basically pieces of branches or roots screwed onto a slate. Their surface has been sandblasted so it is fairly smooth and light colored. The wood darkens when it is waterlogged. I’ve only used this kind of wood once and it didn’t last long enough for me to try attaching plants to it. I find these pieces look very artistic but not very natural, so I tossed the piece I had and replaced it with some driftwood I had collected. If using this kind of wood I would make some grooves on it before attaching a plant.

A fourth option is to collect your own. If you live near a clean lake that is outside a national or provincial park then you are in luck. A lake or reservoir with fluctuating water levels is ideal. Get a measuring tape (driftwood looks a lot smaller outdoors) and hike out to the shore that the predominant wind blows towards. In there you should find quite the supply of driftwood. Once you find a suitable piece and bring it home you must soak it in boiling water. This will kill any water “bugs” living in the driftwood, drive out air trapped in the wood pores, and leach some of the tannin. The latter will turn your aquarium water yellowish or even brown. This is harmless to fish but your significant other may not like the looks of the tank. The tannin will also discolor whatever pot you cook the driftwood in, so be warned. The driftwood can be coaxed to stay submerged by screwing it to a piece of Plexiglas or plastic margarine container full of sand or gravel. Eventually (a few weeks to a few years) the driftwood will become waterlogged and sink on its own.

Now that you have a piece of driftwood it is time to think how to plant the hanging garden. Vertical sections, forks and broad surfaces make ideal planting areas. Java fern can be attached to vertical sections and forks making the driftwood look like it is sprouting leaves. Forks also make it easier to hide fasteners from view. Broad surfaces exposed to light will get covered with algae and make good attachment points for Java moss. The dwarf anubias (Anubias barteri var. nana) can also be attached to broad surfaces.

There are many ways to attach plants to driftwood. One way is to tie the plants loosely with fishing line, this is particularly so with Java moss. Plants with a rhizome can also be stapled or pinned to the driftwood. Make sure the pin or staple does not go through the rhizome but over it. Also be careful so you don’t cut the plant as you staple it. Don’t worry about a few pins or staples rusting in the tank, just make sure you and the fish can’t get scratched by them. If you are lucky the driftwood will have holes you can put a rhizome and a couple of small leaves through, or cracks that you can wedge the rhizome into.

If your Java fern or Anubias arrangement doesn’t look good right away, be patient. It will take several weeks for the plants to re-orient themselves to the light and grow enough to hide the fasteners. Meanwhile the old roots can be used to hide the fasteners or serve as attachment points. The new roots are the ones that will attach themselves to the driftwood. They will find the cracks and crannies in the wood and secure the plant firmly. As the plants grow you may need to trim them a little so the driftwood can still be seen.

These hanging gardens have added a new dimension to my aquascaping. The plants make the driftwood look very natural and the fish love them. I have a patch of Java fern attached to a large piece of driftwood that almost reaches the surface and is near the filter outlet. The Java fern undulates gently in the current and serves as a staging area for my Corydoras sterbai as they dash to the surface for air. The fern also traps food for the Corydoras and preserves the driftwood from the hungry mouths of the clown plecos (Peckoltia vittata) and the bristle-nosed pleco (Ancistrus dolichopterus) that use it as their home. In contrast a piece of driftwood that I left bare is now almost gone, all eaten away.

If you were wondering what to do with that Java fern, Java moss, or Anubias you picked up at the auction here is an opportunity to do something unique. All you need is driftwood and some patience.

*Though that is the trade name, I hope it isn’t really from mangrove trees. Mangrove habitats provide a barrier to sediments that can kill coral reefs and are also fish nurseries. ?