Floating Plants

Fairy moss (Azolla caroliniana)

  • Hardiness: Zones 5-11
  • Height: Less than 1″
  • Flower: Not showy
  • Foliage: Lacy bright green fronds that turn reddish in full sun, forming multilayer free-floating mats 4 cm thick
  • Comments: Leaves normally not eaten by fish; overwinter indoors; naturalized in shallow ponds, ditches and sluggish streams. The sporophyte of Azolla caroliniana commonly survives throughout the year in temperate areas (with hard frosts and prolonged ice cover). It is the best adapted of all species for subsistence on mud.

Parrot feather (Myriophyllum Brasiliensis)

  • Hardiness: 5-11
  • Height: 6″ – 12″
  • Foliage: Small leaves in whorls; aerial foliage have a deeper blue-green color, red stems
  • Comments: Often used in aquariums as an oxygenator; submerged plant but will root and develop aerial foliage in shallow water;
  • obtains nutrients directly from water; soil planting not necessary
  • The larger variety Myriophyllum Aquaticum can become invasive and is being removed from many suppliers availability list.

Water hyacinth (Eichornia crassipes)

  • Hardiness: Zones 8-11
  • Height: 6″
  • Flower: Pale blue to lavendar flowers with yellow spots on 6″ spikes
  • Foliage: Balloon-like petioles swollen with spongy tissue; rosette of pale green, shiny, rounded leaves
  • Comments: Requires abundant sunlight and warm temperatures; long feathery dangling roots;
  • Varieties: Dwarf Hyacinth – grows to 6″ – 10″ in height; Florida Native Hyacinth – grows to 12″ – 18″ in height in Alberta 
  • Invasive in warmer climates
  • water hyacinth

Water lettuce (Pistia stratiotes)

  • Hardiness: 8 – 11
  • Height: 10″
  • Flower: Inconspicuous white flowers
  • Foliage: 10″ rosette of velvety soft green, deeply veined leaves; whitish green on the underside, Feathery roots; 
  • Comments: Prefers shady conditions. Needs to be acclimated to outdoor environment when purchasing from a greenhouse. Strong sun and breeze will dry the leaves if not acclimated.

Water poppy (Hydrocleys nymphoides)

  • Hardiness: Zones 9-11
  • Height: 2- 2.5″ on water surface
  • Flower: short-lived light yellow flowers with a red and brown center, borne in abundance; flowers stand above the water
  • Foliage: Thick, shiny dark green heart-shaped leaves; 2 to 4″ wide leaves on long, trailing stems
  • Comments: Will survive in water up to 12 to 15″ deep, but prefers shallow conditions (6″); prefers rich topsoil; overwinter indoors in shallow tub but keep moist and provide good light

Salvina Natens

  • Hardiness: Zones 7-11
  • Height: ½” high on surface of water. Flotation is made possible by pouches of air within the leaves.  
  • Flower:      None
  • Foliage: The stem is floating, filamentous and branched. Sets of 3 leaves form on a stem: 2 small green hairy ones above water and one that serves as the root structure below the water. These small units reproduce rapidly.
  • Comments: Salvina blocks sunlight from reaching very far underwater and removes nutrients, which also prevents Algae from developing. 

Pennywort (Hydrocotyl Umbellata)

  • Hardiness: 5-10
  • Height: 6” – 8”
  • Flower: none
  • Foliage: Trailing vine growth; rounded leaves suggestive of pennies. When iron is low, the leaves will turn yellow at the edges. Overall growth will be slower, and leaf size smaller when nutrients are lacking.
  • Comments: Grows well in shade ponds and in waterfalls.
  • Massive root system. Can be free floater.pennywort roots

Water Clover (Marsilia Mutica)

  • Hardiness: Zones 6-11
  • Height: Leaves float on pond surface, spreads, and will grow in sun or shade
  • Flower: none
  • Foliage: Leaves resemble a four-leaf clover, and have reddish-brown stripes that splits the darker green on the top half of the leaflets and the lighter green of the lower half.
  • Comments: Plant 4 inches to 9 inches below the surface of the water. It also will grow in damp soil. It is cold hardy but will not survive in temperatures below 10 degrees celcius.
  •  If crowded, it sends up aerial growth in addition to surface growth

FROG BIT (hydrocharis morsus-ranae)

This plant is on the Prohibited Invasive Species list in Alberta. Hydrocharis morsus-ranae spreads rapidly by way of long, cord-like stolons, easily giving rise to a floating mat of interconnected plants. It is capable of over-wintering by forming vegetative buds, called turions, located at the base of the plant.  Hydrocharis morsus-ranae has rapid vegetative spread and the ability to form dense mats, which can limit light penetration and fill the water column in shallow areas. In doing so it can strongly affect native aquatic life. It can also inhibit boat traffic and limit recreational activities.

Water Snowflake (Nymphoides indicum variegata)

  • Hardiness: Zones 8 – 11
  • Height: 6″
  • Flower: White frilly flowers
  • Foliage: Small circular green or varigated pads float across the surface giving a look of miniature waterlilies
  • Comments:  A great surface marginal plant that spreads quickly

 

Water Mint (Mentha Aquatica)

  • Hardiness: Zones 4 – 11
  • Height: 8 – 12″
  • Flower: Miniature lavender-pink blooms that attract many butterflies
  • Foliage: Bright green leaves can be used in teas and jellies.
  • Comments: Spreads quickly, Excellent natural filter planted in biofalls. Grows in sun to part shade.

 

Duck Weed

Duckweed tend to be associated with fertile, even eutrophic conditions. They can be spread by waterfowl and small mammals, transported inadvertently on their feet and bodies as well as by moving water. Duckweed is an important high-protein food source for waterfowl and also is eaten by humans in some parts of the world as it contains more protein than soybeans.The tiny plants provide shelter cover for many aquatic species. The plants are capable of absorbing excess mineral nutrients, particularly nitrogen and phosphates. Duckweed prefer high-nutrient wetland environments, such as sloughs. Often mistaken for algae on a pond. Scoop up some of the plant and if you see tiny little roots – its duckweed.

String Algae

This plant is only being added as many new pond owners do not know what this is. It grows on rocks and plants, as well as any other surface it can attach itself to. Most pond owners like to eliminate it from their pond, as if it is allowed to grow unchecked, it will envelop plants and fish.