My tropicals overwinter in their warm greenhouse climate,
returning to the ponds in mid-June. Zone 4 1/2 allows only a
very short season for waterlilies, about three months.
Each winter I sprout hybrid seedlings in the basement. Then
in the spring a temporary holding tank in my small greenhouse
holds these hybrid seedlings. Whenever I spot especially interesting
hybrid plantlets in the tank, I transfer them outside in mid-June.
To filter the water in the large pond, I employ a Hayward
300 pound sand filter designed for swimming pool use. A wonderful
Tsurumi submersible pump forces the pond water into the basement
through a 1 ½ inch (3.8 cm) PVC pipe. After passing through
the Hayward, the filtered the water flows back outside to enter
the upper pond via a small waterfall. The system includes the
original swimming pool pre-filter and pump. I use them in conjunction
with the Tsurumi pump to backflush the system. To perform this
task, usually every 4 or 5 days in summer, I hook up a small
air compressor to shake up the sand in the filter
as it backflushes. A 50 watt UV light does a great job of keeping
the water clear.
Tropical Waterlily Seedlings
in The Basement