The above authors referred to the use of generic cat litter as a form of hydroponic planting media. The idea fit my situation well, and I have had very good success with water lilies and marginals. Blooms have been good, and I have shared many vigorous rhizomes with Society members, DBG, the Denver Zoo, and neighbors.
- I use ceramic and plastic containers, or tubs, so that my water garden enhances my wife’s terrestrial garden. Containers are easy to maintain, and minimize usage of water and electricity.
- Without a deep pond, plants must be brought inside for the winter. Garden space, and indoor storage space, is limited.
- I would have had to buy heavy soil. Taking it from the lawn or my wife’s garden would have been a problem.
- Each fall, I strip the leaves and roots from each rhizome as if I was dividing the plant. The rhizomes are then stored in small sealed plastic storage boxes with damp sand. The sand supports the rhizome to prevent breakage, and keeps the rhizome damp and above the water (the sand and boxes are dried and reused each year). The boxes are labeled and stored in an attached garage where it is dark and doesn’t freeze. The storage technique allows me to have many different plants without huge storage space requirements, and gives me plenty of rhizomes to share.
I have only tried the type that resembles cat litter because of the above reference.
- It can be expensive when starting out. However, it is reusable year after year. In the fall, I sift out the organic matter, debris and clay binder (from the fertilizer tabs), dry the media in the sun and store it in a dry place. I also purchased the media over time as I added new plants.
- It can “get everywhere”. Minimize spillage by working inside buckets, containers, on trays or hard surfaces. Picking it out of grass or gravel is impossible.
- The media does not clump. When cleaning the rhizome in the fall, the media falls off of the roots when immersed in water. I simply work the rhizome roots with my hands as I am trimming.
- The media does not float after being wetted, although some of the media will float until it becomes wet. When planting, I plant the rhizome the same way as with clay soil, then wet the media from above before placing the planting pot in a container. Placing a rock on the rhizome is essential to keep the rhizome from floating.
- The media does not cloud the water. When dry media is poured from the bag, there is dust, but it dissolves and disappears especially after being wetted from above. I would not recommend breathing the dust.
- I find the media easier and cleaner to work with, in comparison to mud. I do not need to hose off the rhizome with jets of water. I am not working with mud or dried clumps of clay.
- The plants are as easy to fertilize in media as in mud. For lilies and marginals, I fertilize with one tab (from the Club) every two weeks.
- The media works well with any water plants. I use it with lilies, lotuses, Snowflakes, Water Hawthorns and marginals.
- In the spring, I plant the rhizomes as soon as the season appears to start, so as to give the rhizomes as much time as possible to develop their roots. I put the planted pots in buckets of water, and move the buckets of plants in and out of the house as weather permits. I may also place pots in my larger containers, or the in-ground containers.
I use planting pots with fine slits in the sides and bottom. I suspect that the slits and media allow the water and fertilizer to migrate more freely (than with clay) towards the plant roots, and from the pot into the container. Roots are always growing through the slits into the container. I use floating and submerged plants to soak up excess nutrients and control algae.
I do not know how fish will do with the media. I suspect that fish may sweep the media with their fins, or carry the media in their mouths. A layer of gravel could be used to prevent the fish from moving the media.
I have been using “Pond Care Aquatic Planting Media”. It contains zeolite to help control ammonia levels. I have had good luck using it for lilies and marginals.
I recently found a source for generic media that is sold for use on athletic fields. It is “TURFACE MVP”. See also http://www.turface.com for product information. This same product is widely used at DBG and City Park greenhouse for succulents and other plants, which is how I found out about it.
I have not found any generic cat litter, without additives, at local pet stores or supermarkets. If you find generic calcified clay cat litter, be certain that it is not scented, and that it does not have “clumping additives”.