The best aquatic plant choice for a garden pond would be waterlilies. — AFP photo
AT times, we are tempted to have those majestic flowers floating in the lake or river to be grown in our garden.
Yes, water lilies have captured many hearts, just like what happened to my friends who visited my orchard last month. However, the general misconception is as lovely as the lilies are, growing them in a home garden is not possible either because the pond is not big enough or there is simply not enough body of water to hold aquatic plants.
I would like to take the opportunity to explain the various sizes of water lilies and also the methods of growing them in small containers or ponds.
I still have these little beauties in large basin-shaped pots.
So as to satisfy one’s earnest hope to grow aquatic plants in a home garden, I have decided to write it down here to share with you.
1. Various types of aquatic plants that we can grow as a hobby or for landscapes.
⦁ Aquatic flowers vary on size, appearance and their growing attributes. That being said, picking out the right pond plants can be surprisingly tough – some are floating; some are submerged plants; there are bog plants and emergent plants, how the heck do we even start? Floating plants can actually clean the water in the pond, especially one that has gone murky due to the faecal waste from the fish. This is exactly why a very old friend of mine, Mr Song, had once come running to me, asking for some ‘pistia’, or water lettuce.
The pistia is a free-floater appreciated by many pond owners for its decorative lettuce-like growth pattern and also for its easy maintenance.
a) Pistia (Pistia stratiotes) is a free-floater appreciated by many pond owners for its decorative lettuce-like growth pattern and also for its easy maintenance. The long roots provide refuge for young fish and aid in filtering harmful nitrates coming from the murky water.
The water hyacinth is a real jewel of the aquatic world, yet this species is difficult to grow in our climate. — Photo by Peter Prokosch
b) Water hyacinth (Eichhornia crassipes) is a real jewel of the aquatic world, yet this species is difficult to grow in our climate. There were some nurseries, in their attempt to attract customers during the festive seasons, had even recommended for the bulbs to be kept in the freezer to initiate blooming!
c) Hornwort (Ceratophyllum demersum) or commonly known as coontail, is a species of submerged, free-floating aquatic plant with a cosmopolitan distribution, but it was a harmful introduced weed to the Kiwi Islands. It has allelopathic quality, in that it excretes substance to inhabit other phytoplankton and blue green algae. It is used as a model for studies of plant physiology, apart from for the breeding of a number of fish species.
d) Duck weeds and water lentils are a sub-family flowering, floating aquatic plants inhabiting wetlands or slow-moving rivers and ponds. It reproduces asexually by cloning itself continuously. It can easily become a weed clogging waterways.
e) Nymphaea (waterlily) and Nelumbo (lotus)
The best choice for our garden ponds would be waterlilies. What about lotus? These jewels of the aquatic world have been symbolic in both ancient and modern times. These are celebrated for their beauty, and have been immortalised in many arts and religions. Fragrant blooms are a lovely addition to fish ponds. The key to success is to have enough sunlight and sufficient nutrients for plants being embedded in containers.
These are herbaceous perennial aquatic plants that are differentiated by the way they grow – a waterlily tends to sprout from the bulb or corm in the water or mud, but the lotus would hold its leaf above the water surface and it produces stolon roots for food; China exports this crop to our market too.
The colour types of a water lily are blue, purple, yellow, red, white, pink and orange as well; lotus is usually white, pink or yellow. On types, there are hardy and tropical types. Here, we have only the tropical varieties such as the day-blooming water lily. There are several dwarf versions (Nymphaea pygmaea helvola) that are suitable for small vessels meant as indoor displays under full-light condition.
There are two types of lotus – N. nucifera and N. lutea, different in growth regions as in Asia and Australia, against the American lotus with yellow flowers.
2. How to grow waterlilies?
⦁ First, suitable site for planting – it can either be in a pond or in a large shallow basin. Obtain the rhizome and divide it into sections for more planting, or just regrow it for pond-planting; it is better to use a plastic porous basket with holes on the sides. Line the holes with fabric to hold the medium without leaking it into the water.
⦁ Soil or medium – fill it to the brink of the container and bury the rhizome, except the growing point, which needs to be above the soil level. Keep it to one side of the container. This should allow the roots to grow out properly. Fill in some gravel to cover the soil to avoid spelt into the water as it is being lowered into the pond – a depth of one to two feet is good. Never use potting mix as the lighter content would float. Use the top soil, can do.
⦁ Water level – adjust it to the depth required and leave enough room for the spreading leaves. A small pot is good for the mini varieties, but not suitable for the large ones.
⦁ Fertiliser – it works best to insert pellets of slow-releasing fertiliser in the medium close to the growing rhizome. Loose fertiliser needed to be packed in cloth before putting it in the medium. Do not throw the fertiliser into the water as this could change the pH level, which is bad for the fish and also the plant.
3. Pruning
⦁ Waterlilies would open under the morning sun and in the afternoon for a few days, or fall into the water where seed pods would be formed. The ripe seeds would be embedded into the soil below and eventually, germinate into a new plant. Pruning the ageing leaves and the old flowers would ensure more blooms.
Happy gardening!