Adding pond plants to your pond and understanding their role for maintaining a healthy pond
Although it is probably the fish that provide the biggest wow factor in ponds, especially when it contains large colourful fish such as KOI. It is the combination of both fish and aquatic pond plants which make for some of the most beautiful and natural looking ponds. Plants can also have a big effect on the overall health of your pond and if correctly balanced will make you pond much easier to maintain.
Plants produce oxygen for your fish and will also use/remove much of the nutrients that would otherwise be used by blanket weed or algae. This means adding the correct amount of plants will go along way to helping ensure your pond stays green water free! It is not to say you need plants to have clear water but Without them you would need to spend more on pond equipment such as aerators as well as an additional or more powerful filter, UV lamp or pump. Therefore even if you are going for a Koi pond where plants are unpopular and are eaten by the fish, you could still create a small second pond for a waterfall to flow from or into where your plants could be planted.
Once your pond is built and contains water you can add your plants straight away remembering that different plants perform a different job. The first essential type that must be added if you are keeping fish are oxygenating plants, these add oxygen into the water for the fish to breath. Many other varieties of plants can be added to make your master piece more attractive and well balanced. Aquatic plants generally fall into one of these categories:
Deep under water plants such as Water Lilies
Deep water Aquatic plants like these such as hyacinths and soldiers and water lilies root into the bottom of the pond and grow up to the surface where flowers and leaves project on or out of the water.
As well as looking beautiful, water lilies provide the essential service of covering a percentage of the water surface from the sun. When the sun shines directly onto your pond it provides algae and blanket weed with the ideal conditions they need to survive and rapidly grow. That is Sunlight and water, much like any other plant. Obviously you can combated this somewhat with a well planted pond but covering the water and stopping the sunlight getting in will also stave the algae of the sunlight it needs and help maintain clear water.
When you first get your lily it is best not to just drop it straight into the water before any leaves have grown. Suspend it 4-6 inches under the water until several leaves have grown to the water's surface and then gradually lower it to the desired depth depending on variety, which can range from 6" to 30" depending on size. Please note until your lily is fully established and has a healthy root system the leaf quality or flower colour may not be at its full potential.
Oxygenating plants grow under the water's surface and help pond life by giving off oxygen bubbles into the water. They also absorb the mineral salts used by algae so having enough of these can be very important for a health pond. See here for more details about Oxygenating plants
These aquatic plants float freely on the surface of the pond and do not need to be planted in a pot or soil. As well as providing shade for your water they can also be excellent natural food for your fish. There are many varieties of these available such as duckweed, frogbit and azolla.
This category contains the largest variety of aquatic plants withg many varieties of grasses and flowering plants. They generally sit on a shelf a few inches under water with most of the plant being above the water's surface. These generally come already planted within a pot and you simply sit them on a shallow shelf in your pond or within a boggy area.
Bog plants are similar to marginal's but simply sit in a bed of wet mud.