Spring is just around the corner and we just can’t wait to get our hands dirty – and wet, at least I can’t! Included among my gardens are quite a few ponds, both formal and informal, casual, sun, and shade, with one even inside a greenhouse. Water gardens are just like earth gardens, offering seasonal interest and tasks, except mercifully little weeding is involved.
If you neglected to clean your pond in the fall, now is the time to do it. Clean and remove all dead leaves and rotting organic matter. Check your pump for debris near the inlet, as well as for frayed electrical wires or signs of oil. If you detect any oil, replace the pump immediately, as leaking oil can kill both fish and plants. If your pond is home to a good number of fish, add a filter starter to your biological filter to get things going. For ponds with just a few fish, this is not necessary, as the filter will start itself. Lastly, ensure the electrical outlets are ground fault outlets, as too many people fall victim each year to the deadly combination of water and electricity.
Most water plants are heavy feeders, so now is a good time to feed them. The easiest way is to use water-garden feeding tablets, which you simply push into the soil near the roots. These tablets are specially formulated to slowly release the correct balance of plant food. Be sure to follow the instructions on the packet, as too much fertilizer risks clouding the water. Understand that the plant food will also nourish the algae, which will turn your pond water green. For plants that are outgrowing their containers or are too big for their location, now is a great time for dividing. My rule of thumb is to divide about one-third of my plants each year, so that each pond is only partially disturbed; water lilies should be divided about once every five to six years.
Remember that bodies of water take a lot longer to warm up than the earth in your flower or vegetable garden. Nonetheless, this is the start of the water garden year. Even though the plants in your garden seem to be bursting out of the ground while your pond is just sitting there in a dormant state, it won’t be long before your water lily pads appear, along with the frogspawns.
One of the earliest plants to bless your pond is Caltha (marsh marigold). This is one of the most popular of all the marginal plants. Also known as kingcup, Caltha palustris is a bright-yellow waxy flower, which holds its head proudly above heart-shaped leaves on a 30- to 45-centimetre stem. These grand leaves make an impression in your pond even when there are no flowers. C. palustris ‘Flore Pleno’ has cute double yellow pompom flowers that appear above nice compact mounds, 15 to 30 centimetres high. Often these plants are completely decked out with flowers. This plant is ideal for any size water garden. C. palustris var. alba is compact with white flowers, and stands 15 to 30 centimetres high. The unfortunate aspect of this plant is that it tends to be inconsistent, sometimes blooming well, and other times poorly. A better white is C. leptosepala, which is a mid-sized marsh marigold with beautiful white flowers.
This plant is often difficult to find. Now for the really big one, try C. polypetala, which reaches up to 90 centimetres high and has large yellow blooms. This plant is not for small ponds but is superb for sizeable ones.
Not many of the plants have the attributes of Aponogeton distachyos (water hawthorn), which usually blooms both in the spring and autumn. This water plant has lovely oblong leaves with brown blotches. It can spread up to 60 centimetres wide, and remains one of very few plants I have found that does well in moving water. Each flower has waxy white petals and black anthers. The flowers emit the most beautiful vanilla fragrance, making them a joy around your pond.
Another of my favourite plants, which is seldom used, is Lysichiton americanus. Its lack of popularity may be due to its common name, “skunk cabbage.” This plant has had a bit of a false rap, as it grows naturally in swamps where the smell often comes from the surrounding rotting vegetation and stagnant water. While worthwhile growing, Lysichiton is not for the small pond as its beautiful leaves can easily reach 90 centimetres long with an arum-like flower with a yellow spathe often 45 centimetres high. There is also a smaller white variety, L. camtschatcensis, about 60 centimetres high with nice white spathes.
Meanwhile, other life in your pond, such as your fish, should be starting to come to the surface. It’s okay to feed them but don’t use a protein food – your fish have spent many months not eating at all, so it is best to start them off slowly. I recommend giving them Cheerios – yes, Cheerios! If you have koi, and the temperature in your pond has reached 7°C (45°F), now is the time to feed them brown bread with natural yogurt on it, then follow with Cheerios. As koi do not have a stomach, the yogurt helps to kickstart their digestive system following a long fasting period.
Now, with the emergence of our fish and our pond plants, we can once again start to really enjoy our water gardens.
Past president of both a koi club and a koi and water garden club, Merv Zakus has been building water gardens for more than 15 years.