Water Gardening

Where a water garden grows, beauty and tranquillity flows! It’s easy to bring your beloved body of water back to life with stunning plants and flowers that add colour and texture to the environment. Transform your pond into a tropical oasis by planting these bold beauties available at GCA Garden Centres this October. Here’s our shortcut to a sure-win water garden. 

Louisiana Irises

These easy-going, seductresses of the pond are simply a must for the backyard oasis. Louisiana irises can be grown in pots, raised beds, dug out beds, shallow water, and at the edge of ponds or streams. They produce bold, flamboyant flowers from September through October in all the glorious colours of the rainbow, ranging from pure white, yellow, orange, red, purple, violet, magenta, blue, lilac and pink. Louisiana bloom best in full sun, but will make do with part-time dappled shade. The price to pay for this beauty is a lot of feeding! Visit your nursery for Bio Ocean, which you can serve at least twice a year during autumn (when they should be replanted) and again about a month before they flower in spring. 

Nymphaea – aka Waterlilies

Nymphaea are total water nymphs and have lured many a wary green thumb into a lifelong devoted relationship with water gardening. While individual blooms may only last 3 to 4 days, a well fertilised Nymphaea will flower profusely from September through April. Their exquisitely perfumed blooms come in shades of white, yellow, peach, salmon, pink, red and blue, which rest gracefully above their floating leaves. Waterlily leaves provide shade and cover for fish, while offering a handy perch place for bees, frogs and other friendly pond critters. They require full sun, all day, and prefer tranquil waters with a depth of 15 to 50 cm above the plant’s container. Transplant waterlilies into larger pots using aquatic plant soil (available from GCA’s) and fertilise regularly with Bio Rock Root Builder.

Colocasia – aka Elephant Ears/Taro

With a handsome host of colours and textures to choose from, bring the jungle to your backyard oasis. Add character to your pond by planting Colocasia esculenta ‘Tea Cups’ with attractive tall, dark-burgundy stems topped with quirky up-turned leaves, just like giant teacups. Get fancy with Colocasia antiquorum ‘Black Beauty’ and ‘Illustrous’ – these medium-sized elephant ears have luxurious velvety-black leaves and thrive in full sun or dappled shade. Elephant ears have a jungle-sized appetite and thrive in rich, moist, organic soil or shallow water at the pond’s edge. If your elephant ears are sulking, feed them with Bio Ocean and give them more water, or better yet, relocate them to your pond and live on the wild side! 

Thalia – aka Alligator Flags

Nothing says tropical like lush, overlapping foliage. Thalia dealbata and Thalia geniculate will certainly deliver with their bold paddle-shaped foliage, parading in and around your pond. Thalia dealbata has dusty blue-green leaves, whereas Thalia geniculata has eye-catching red stems. They flower during summer and will flourish in full sun, performing best in rich clay-loam, sandy and mucky, moist to wet soil. Try growing these island-style beasts in large pots to add height and ambiance to your water garden oasis. They have no serious pest or disease concerns and are excellent additions to bog gardens and ponds of varying sizes, growing in standing water of up to 60cm deep. An added bonus is that Thalias are super winter hardy, withstanding temperatures as low as -17° C.

Cyperus –  aka Sedges

These statement-making perennials are often overlooked as background or filler plants, but they can easily start a vibe on their own. The Giant Egyptian Papyrus (Cyperus papyrus) boasts towering mop-heads that offer a thread-like explosion of green fireworks – how’s that for trend-setting? The dwarf Cyperus prolifer has neat and compact, tuft-like leaves that effortlessly bring in sophistication to the backyard oasis. Try also the Umbrella Sedge (Cyperus alternifolius), a medium-sized alternative, with drooping, ribbon-like parasols atop bright green round stems. Sedges prefer full sun for strong growth and like moist soil or shallow areas where their arching stems can droop flirtatiously over the water. They are also a favourite nesting site for Weaver Finches, so that’s certainly a bonus! 

Top tips to keep your water plants blooming

Transplant your newly acquired water plants into larger pots, keeping their mature size and your available space in mind. Use a 50:50 mix of potting soil and garden loam with some added Bio Rock Root Builder mixed in for all your marginal aquatic plants and irises, to keep them lush and beautiful. Top with a layer of river sand or gravel to prevent the potting soil from floating out.

For waterlilies use a specially formulated aquatic plant soil or mix your own using 1 part very well composted kraal manure to 4 parts garden loam, with Bio Rock Root Builder added to the mix to keep them blooming. A 50 cm basin works wonders and can last a waterlily for 2 seasons.

For koi ponds where it is important to maintain good water quality and limit nitrates and ammonia in the water, marginal aquatic plants can be planted in washed gravel, but they will not grow as lushly as they are solely reliant on the available nutrients in the water (and will help keep the water clean). 

Feed your water plants as they are heavy feeders and will quickly exhaust all the available nutrients in their growth media, particularly in small cramped pots. Use Bio Rock Root Builder, organic or slow-release fertilisers (Bio Ocean), and apply by making a hole in the soil next to your plant. Make sure to administer the correct amount of fertiliser (as per the manufacturer’s instructions) and then remember to cover it with soil. Waterlilies in small pots can be fed with Bio Rock every second month throughout the growth season (September through March).

Prune yellowing and dead leaves regularly to keep your pond looking neat and to prevent organic matter from accumulating and decaying in your pond.

Keep an eye out for pests, such as aphids on waterlily leaves and marginal plants. If possible, remove and isolate infected plants from the pond and treat with appropriate organic insecticides. Rinse plants thoroughly before returning them to the pond if there are fish or wildlife present.

Though they are not generally considered pests, koi and ducks can make a quick meal of water plants. Care and should be taken when planting to protect your treasures from these ravenous beasts. 

Ponds and water gardens are a gorgeous way to attract wildlife to the garden as they provide a waterhole for thirsty bees and birds, as well as much needed breeding ground for frogs, toads and dragonflies. Include sufficient shallow areas around ponds to provide easy access and exit routes for frogs and toads and their young can often drown if they cannot escape. Enjoy all the wonders water has to offer this summer.

Source: Life is a Garden