Read about Joe Tomocik


Nymphaea 'Cynthia Ann'

 Diary of a Professional
Water Gardener

Chapter 3
Fall 2007

by Joseph V. Tomocik
Click images to enlarge


This year I have taken seven trips lasting from two to eight days in pursuit of native trout.

The similarities of trout waters and water gardening are striking! It seems that my visits with the "trout fly" soon relate back to water gardening and my work at Denver Botanic Gardens.

In late September I visited the exciting Deschutes River in Oregon with my brother Tom. The Deschutes is a world-class fishery draining the Eastern slopes of the Cascade Mountains. It flows north into the Columbia River, which eventually spills into the Pacific Ocean.

Common to the mighty Deschutes is an abundance of volcanic-origin lava rock, steep canyon walls, rattlesnakes and an impressively managed fishery. Representing an excellent example of a sustainable ecosystem, the Deschutes is lined with an abundance of expertly maintained convenient picnic and parking areas. The way to the prime fishing holes is steep and dangerous. Steps are a blessing to the anxious anglers.

Only two trout 11-13 inches (28-33 centimeters) can be kept. Regulations are clearly posted. One gets the idea that the quality of fishing and integrity of the area will long be in tact. Leading botanic gardens including Royal Botanic Gardens, Missouri Botanical Garden, North Carolina Botanical Garden and Denver Botanic Gardens are entrusted to play leading roles as stewards of the environment. 

Green Team

Denver Botanic Gardens operates a task force, the Green Team, to promote conservation and sustainability. For example, they placed numerous receptacles throughout the Gardens and designated Thursday as the day to take the bus, walk or bicycle to work. The Green Team oversees procedures to dispose of waste properly.

Last summer we completed a major renovation of the Japanese Garden pond using the latest and most efficient methods and materials. Two old water pumps force water through our main waterway. New water- and energy-saving VFD (variable frequency drive) pumps will soon replace them.

An extension of conservation is prolonging and enhancing the quality of life. Denver Botanic Gardens will again enthusiastically display next year Nymphaea 'Pink Ribbon' (Songpanich), a recent plant introduction spearheaded by WGI. A portion of the sales from the plant will go to fighting breast cancer.   

Redsides Trout and a Favorite Marliac Waterlily

The native resident rainbow trout of the Deschutes (Oncorhynchus mykiss gairdneri) is acrobatic, strong and shaped like a football. Upon first seeing the "redsides" trout, I associated it with one of my favorite small hardy waterlilies. When I saw this gorgeous trout described as "brick red", I knew I was on to something.

Nymphaea 'Indiana' (Marliac) has long been one of my favorite tiny hardy waterlilies. It too is "brick red" and distinctive. It has a tight Marliac root and grows well in a two-gallon (7.6-liter) container. It is excellent for container gardens. Anyone having this waterlily has a real gem!


Horsetail on the Deschutes

Dramatic sunsets, cascading falls and heron are all part of the magnificent Deschutes. Horsetail (Equisetum laevigatum) thrives there too, just a bit above the riverbed.

Earlier I had seen E. arvense along the South Platte drainage near Denver, CO. With a near cosmopolitan distribution, the horsetails are also called scouring rush, as the stems can be useful in scouring pots. Sold as herbal remedies, horsetails are suggested to be effective if treating kidney and stomach ailments.

With jointed, decorative hollow stems, the spore-producing horsetails are wonderful ornamental aquatic plants sold by many quality nurseries. The compact and easily cultivated dwarf horsetail (E. scirpoides) grows to eight inches (20 centimeters).  

On the Way to the Gardens…

I have always marveled at the landscaping, bubbling fountain and clear water of an exclusive apartment complex not far from my home. Just a couple of days ago I noticed the pond had an unsightly algae bloom. And the fountain was not functioning! 

Three summers ago at the Gardens' Monet Pond, we added two fountains with a timer and adjustable jets. The fountains aerate the water, making it difficult for algae to take hold. Their softly falling water makes gentle music for the ears and a striking visual impact for the eyes. Fish survive better in the oxygenated water.

Moreover, every morning a rainbow appears!

Adding a single feature produces five benefits. How is that for being efficient?  

What do you do with them in the winter? Hardy Waterlilies!

And so you now have the most frequently asked question about our water gardens. My reply is often, "Which plant are you asking about?"

Visitors are a bit startled when I explain that we have plants from Alaska to South America and Africa.

With our minimum winter temperatures at times reaching -20 F. (-29 C.), Denver, CO., is in USDA Plant Hardiness Zone 5. Most hardy waterlilies survive outdoors to Zone 5. Thus, they successfully over-winter outside in our Gardens. We take steps, if necessary, to insure that the rhizomes do not dry out or freeze.

Beginning the last Sunday in September, the very capable Colorado Water Garden Society volunteers assist with our over-wintering chores. They remove hardy waterlilies from the pools and place them in one of several locations.

We store them in metal tanks or rubber tubs between our greenhouses after removing leaves for sanitation reasons. During the first or second week in December, we place two-inch (5-centimeter) foam sheets in the tanks and then cover them with plywood. We remove the foam and plywood during the first week in March. The loss with this method is zero or minimal.

We move other hardy waterlilies into bins or bring them together in two groups in the Monet pond, which is now drained. These plants are then covered with bags of leaves or pine needles two- to three-inches (five- to eight-centimeters) high. It is important that you cannot see the pots as you peer through the bags of mulch. If there are gaps, plants will freeze and be lost or severely damaged from the cold and freezing temperatures.

Hardy waterlilies can also be lowered to the bottoms of pools. Larger pools are much safer than small pools. Each situation is truly different and should be carefully monitored. Sometimes we may need to apply additional mulch. Having two-three inches (five-eight centimeters) of ice form in our tanks is not enough to damage the plants.

Denver's cold winters and nights are partly responsible for the exceptional performance of hardy waterlilies in Colorado. Not allowing them to enjoy a long, cold dormant period seriously affects their health and performance.

See you at poolside,
Joe T.   

WGI ONLINE Journal Table of Contents

Water Gardeners International
Home | Join WGI | Members' Exclusive | Gateway to Water Gardening