Dividing aquatic plants, and providing fresh water

It is springtime for plants in the greenhouse, including aquatic plants which are adapted to having their roots always damp or entirely submerged in water.

Before plants get too far into the new spring season, now is a good time to address the overgrown roots from last season. One option for an overgrown plant is to divided it into two parts; or, the root ball can be cut down to a smaller size; or, more simply, a plant might be moved into a larger pot. Today, I was directed to use all three techniques for some of the aquatic plants.

Umbrella sedge Cyperus alternifolius

A clean tank and water, with repotted plants at the far end

With the plants removed from the tank for repotting, it was an opportunity to replace the murky water in the open tank. But, it is not only the tank water needing to be replaced. The majority of the dirty water sits in a large reservoir below the tank. A pump in the reservoir pushes water up into the tank to find its way back down through drain holes. Over time, the water becomes murky without critters and natural filters used by Mother Nature to keep her waters clean.

Today, approximately 50 gallons of water had to be drained from the open tank, and 200 gallons drained from the reservoir. The process took about 2 hours to complete. The water used to replace the dirty water was filtered and deionized by reverse osmosis (RO). The water comes from an osmosis system installed in the basement of the greenhouse and pumped up to the various rooms.

Care must be taken to ensure the plants are grown in RO water. Aquatic plants are not adapted to the strong concentration of minerals found in tap water.

Overgrown plants and dirty tank water, waiting to be replaced

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