A pond of any size is a soothing and visually peaceful feature in any backyard. But no pond is quite complete without the addition of water plants. And while looking after water plants isn’t difficult, it helps to have a little know-how before you get started.
Location, Location, Location
Water plants are fussy about the conditions you give them, so before you start digging consider where you are locating your pond. The shade of a large tree, for example, may look inviting on a steamy summer’s day, and the thought of trickling and gurgling water completes the picture, but most water plants won’t be happy with too much shade. In fact, water plants typically prefer full sun and for water lilies it is an absolute must.
Plants make a pond look natural and add beauty to your landscape. They also help to keep your pond’s ecosystem in balance by absorbing toxic chemicals from the water. They shade the water to help reduce algae, and they also provide cover for your fish. It’s wise to grow a few different types. Here’s a primer to get you started:
- Deep Water Aquatic Plants
Water lilies (Nymphaea) are by far the gardener’s most popular choice. While their roots and stems are submerged and anchored at the bottom of the pond (often in a pot) the leaves and flowers float above the water. Some forms are hardy types, available in white, yellow, red, pink and apricot, and survive cold winters. Others are tropicals and though they are frost tender, they are worth considering anyway. Tropicals come in the blue to purple colour ranges, which don’t appear in the hardy types. They are often enormous in size and have a gorgeous fragrance that is unmatched, with some types blooming in the evening. Tropicals generally cost more than the hardy types, but their attributes make them a worthwhile indulgence.
- Submerged Plants
Submerged plants oxygenate your pond and help to keep it clean. Oxygen is released from the foliage during photosynthesis and passed directly into the water making it able to support other forms of life (like fish). Submerged plants absorb minerals dissolved in the water and help to suppress algae by competing with it for nutrients.
- Marginal Plants
Marginal or bog plants grow at the pond’s edge in shallow water. They are an important ornamental element in most ponds. As well, they attract a variety of wildlife and aquatic insects to the pond.
- Free Floating Plants
Free floating plants have roots that dangle in the water, and get all their nourishment from the suspended roots. The floating foliage provides shade for fish, and reduces the amount of sunlight reaching into the pond, thus helping to reduce algae. It also plays an important oxygenating role in the pond.
Algae and Mosquitoes
The most frequent problem associated with water gardens is the growth of algae. Algae are encouraged by sunlight. A good rule to follow is to try to have at least 50% of the water surface covered with plant material. In so doing you reduce the amount of sunlight that gets to the bottom. Scavengers like the trapdoor snail and the use of oxygenating plants will also help to reduce algae.
Since water is the mosquito’s favourite breeding habitat, your pond will inevitably attract them. You can control mosquitoes quite easily by introducing fish into the pond.
Fish for Your Pond
Different species of fish have different needs, so it’s important to consider carefully the kinds of fish you introduce to your pond. Fish feed at different water levels, so make sure you can offer them a pond deep enough for their dining preferences. Koi for example, require water about a metre deep. Garden centres that sell fish usually have knowledgeable staff who can help you decide which fish are best suited to the pond environment you have to offer.