Water gardens, also known as aquatic gardens, are a type of man-made water feature. A water garden is defined as any interior or exterior landscape or architectural
element whose primarily purpose is to house, display, or propagate a particular species or variety of aquatic plant. Although a water garden's primary focus is on plants,
they will sometimes also house ornamental fish, in which case the feature will be a fish pond.
Although water gardens can be almost any size or depth, they are typically small and relatively shallow, generally less than twenty inches in depth. This is because most
aquatic plants are depth sensitive and require a specific water depth in order to thrive. The particular species inhabiting each water garden will ultimately determine the actual surface area and depth required.
When the aquatic flora and fauna is balanced, an aquatic ecosystem is created that supports sustainable water quality/water clarity. Elements such as: fountains, statuary,
waterfalls, boulders, underwater lighting, lining treatments, edging detailing, in-water and bankside planting and watercourses can be combined with the pool to add visual
interest and integration with the local landscape and environment.
Stream gardens:
On a constructed stream, placing rocks in the path of the water makes small patterns, rapids and waterfalls. The rocks disrupt the waterflow, causing splashing and bubbles to form,
which can make pleasant sounds and micro-habitats for plants , fish, and wildlife. Well placed rocks can stimulate splashing water that adds oxygen to prevent hypoxia,
with the more bubbles - the more dissolved oxygen in the water.
Aquatic Flora:
Water garden plants are divided into 3 main categories: submerged, marginal, and floating.
- Submerged plants are those that live almost completely under the water, sometimes with leaves or flowers that grow to the surface such as with the water lily. These plants are placed in a pond or container usually 1–2 ft (0.30–0.61 m) below the water surface. Some of these plants are called oxygenators because they create oxygen for the fish that live in a pond. Examples of submerged plants are:
- Water lily
- Hornwort
- Marginal plants are those that live with their roots under the water but the rest of the plant above the surface. These are usually placed so that the top of the pot is at or barely below the water level. Examples of these are:
- Iris or Flag
- Water-crowfoot
- Bulrush
- Cattail
- Taro
- Arrowhead
- Lotus
- Pickerelweed
- Floating plants are those that are not anchored to the soil at all, but are free-floating on the surface. In water gardening, these are often used as a provider of shade to reduce algae growth in a pond. These are often extremely fast growing/multiplying. Examples of these are:
- Mosquito ferns
- Water-spangle
- Water-clover
- Water Lettuce
- Water Hyacinth
Algae:
Algae are found in all ponds. There are hundreds of species of algae that can grow in garden ponds but they are only usually noticed when they become abundant. Algae often grow in very high densities in ponds because of the high nutrient levels that are typical of garden ponds. Generally alga attaches itself to the sides of the pond and remains innocuous. Some species of algae, namely the dreaded 'blanket weed' can grow up to a foot a day under ideal conditions and can rapidly clog a garden pond. On the other hand, free floating algae are microscopic and are what cause pond water to appear green.
Fauna:
Fish
Often the reason for having a pond in a garden is to keep fish, often koi, though many people keep goldfish. Both are hardy, colorful fish which require no special heating, provided the pond is located in an area which does not have extremes of temperature that would affect the fish. If fish are kept, pumps and filtration devices are usually needed in order to keep enough oxygen in the water to support them. In winter, a small heater may need to be used in cold climates to keep the water from freezing solid. Examples of common pond fish include:
- Ricefish (Himedaka)
- Mosquitofish
- Rosy Red Minnows
- White Cloud Mountain minnow
- Goldfish (Common, Comet, Shubunkin varieties, Wakin and the Fantail varieties. With the possible exception of some of the fantail varieties, the fancy goldfish are not suited to pond life.)
- Crucian carp
- Koi (Nishikigoi, Butterfly Koi and Ghost Koi)
- Mirror carp
- Carp
- Weather loach
- Golden Orfe
- Golden Tench
- Eel
- Catfish
- Bluegill
- Black bass
- Snakehead
- Goby