Notes On The Cultivation Of Aldrovanda Michael Hammond 9624 Aspen Place, Manassas, Virginia 20110 USA mormhammond@aol.com August 14, 2003 As a hobbyist interested in carnivorous plants I've never had much luck in growing Aldrovanda. I've tried growing them in all kinds of bowls and aquaria. I've used the purest water and maintained it at a low pH. Once I even brought home a quart or so of the actual water in which the Aldrovanda were growing. What invariably happened was the plants became smaller and smaller until they disappeared. Then I was informed that Aldrovanda should be grown with other companion species of aquatic plants. Since I had a number of outdoor water tanks with various potted and floating water plants growing in them, I decided to give that method a try. I used several 30 gallon tanks and even a 240 gallon rubber lined tank. I floated the Aldrovanda among the potted water lilies and strands of Elodea. As the weeks passed I watched my incredible shrinking Aldrovanda. Hope springs eternal and this spring I had new hope. On my patio I have a nearly 1000 gallon rubber lined pond with a 26-sq. ft. sand and peat bog at one end. All kinds of plant and pond life were growing in this bog pond including several fantail goldfish to police up any mosquito larvae that might be missed by the dragonfly naiads and diving beetles. My plan was to fence off a small area in the shallow water among some plants adjacent to the bog. I stocked the enclosure with this spring's purchase of ten Aldrovanda strands. By the middle of June it was evident that these poor plants were on death row. The source of my Aldrovanda has been Meadowview Biological Research Station in Woodford, VA headed by Dr. Phil Sheridan. As often as I am able, I do volunteer work for Meadowview. One day in June Phil asked how my Aldrovanda was doing. I sadly and somewhat ashamedly reported that it was slowly declining as in the years previous. He suggested I take a few more strands home with me gratis since I had sweated pretty good that day. I declined and told him I was reluctant to doom anymore plant material to certain death. Phil said, why don't you take some pond sediment from the Aldrovanda growing area along with the Aldrovanda. Grow them in an aquarium with some companion plants. With renewed hope, I left that day with ten new strands of Aldrovanda in a gallon of Meadowview pond water and a good shovel full of Meadowview pond bottom sand and muck. When I arrived home I sat up a ten-gallon aquarium as follows: Bottom sediment from Meadowview was added to the aquarium along with Utricularia, Sparganium, and Sagittaria. I added a few plants from my bog pond, Juncus, elodae, potamogeton and an unknown plant from the Po River near Meadowview. The aquarium was then filled with rain water and topped off with the ten strands of Aldrovanda and the gallon of Meadowview water. In an effort to be a little scientific I used a water test kit called Quick Dip from Jungle Labs, Inc. These are the results of the test on the new Aldrovanda set up:
Nitrate 0 Nitrite 0 Total Hardness - 25 ppm (GH) very soft Total Alkalinity - 0 (Low) pH - 6.2 I double checked the pH with another type of wide range pH test kit and got a reading of 5.5. I placed the aquarium outside in the full sun. It settled out nicely but did have one algae bloom which I expected. I'm happy to say that the Aldrovanda has thrived. Some of the strands even branched. As the tips grow, the older proximal ends necrotize and eventually fall away. My strands ranged from 3.5 to 5 inches long About the first week of August, hook shaped flower heads appeared near the growing tips.