The Oakland Press – Water Gardens
The Oakland Press
“Water, like fire, is a good servant, perhaps, but is painfully liable to develop into a master.”
That’s what R.J. Farrer wrote about water gardening in 1908. And, he added, it is “cruelly hard to keep in order and control.”
Of course, in Farrer’s day it was devilishly difficult to build and maintain a water garden with plants and fish. Extensive plumbing, large, high voltage pumps and a truck full of concrete was necessary to put it altogether. In short, true water gardens with all their diversity were strictly for the wealthy.
Today, thanks to the development of plastics and polymers, water gardens are affordable and incredibly easy to install. Thick waterproof liners eliminate the need for concrete. Low-voltage miniature pumps move and aerate water continuously.
Now, enchanted with my new water garden, I had no idea just how static my landscape had been. The small pool and waterfall became the epicenter of life in the landscape, and took on almost magical ambiance.
But despite the ease of construction, the long-term care still can be cruelly hard to keep in order and control. Look for the simplest oversight to trip you up.
For the first year or two my large in-ground water garden functioned perfectly. I’d planted in with water lilies so their flat surface leaves would shade the water and keep fish cooler in the summer. I used aquatic butterfly iris for architectural interest, Horsetails and rushes offered unique textures. All of these plants grew in plastic pots that sat underwater at varying depths.
During the warmer months I planted annuals in the water. These were “floaters” which did not anchor in soil at all. My water hyacinth and water lettuce dragged their roots through the water, extracting nitrogen to naturally control algae bloom. They were continually moving, creating new compositions from moment to moment.
Reluctant to incest in expensive koi fish. I stocked the pond with the cheapest feeder gold fish I could find. Twenty cost me $10 at a pet shop. They adapted well to their new outdoor environment and grew at a startling rate.
And then in year three the algae bloomed, No matter what I did it just wouldn’t quit. Changing the water, changing plants and skimming daily did not seem to phase it. Even a double dose of floaters didn’t help.
Only then did I realize those 20 tiny gold fish were now big fat mature goldfish the size of trout. Each one consumed food and excreted waste that was loaded with nitrogen.
Nitrogen is essentially fertilizer, and it created such a rich environment that algae, which are plants, flourished, In the summer months is exploded at a startling rate. I fought it and fought it until the realization that it was the fish that caused it sank in. The 20 Large Fish in a small pong excreted more nitrogen than the floaters and other plants could extract. All my work and worry to diagnose the algae problem was solved in five minutes. I kept the five best goldfish and gave away the rest to a friend starting their own ponds. The algae problem corrected itself; harmony returned to my water garden.
The lesson of the too-large goldfish illustrates one great truth about water gardening. Things are always in a state of flux. Fish are always growing. Plants are too. Even climate anomalies take their toll.
The need to divide plants is ongoing because these grow twice as fast as terrestrial species. They’ll outgrow the pot quickly, often in a single season, sending bundles of roots out into the water. Trimming and tending is essential to maintaining the vital balance of water, plants and fish.
Water gardens can be easy and they can be hard. When you don’t tend them diligently it takes but a few hot days to turn as inspirational koi pond into pea soup. Ignore it and you’ll surely meet a most demanding master, cruelly hard to keep in order and control.
By Maureen Gilmer
(Maureen Gilmer is a horticulturist and host of “weekend Gardening” on DIY Network. E-mail her at firstname.lastname@example.org.)