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Southeastern USA 

For quick success with waterlily seeds, tubers and Victoria --

Get Yourself into Hot Water!

by Rich Sacher, New Orleans, Louisiana

Many waterlily and Victoria growers have discovered that a warm 90° F (32° C) hot tub treatment stimulates tropical waterlily seeds and tubers into growth. Here's how I do it.

The Hot Tub 

I use a black plastic tub, two feet (0.6 meter) square and one foot (0.3 meter) deep, for my greenhouse hot tub. I put two 1500-watt aquarium heaters in this tub, and keep it filled with water. One heater suffices; the second one is insurance in case the first one fails. I set the heaters at 90-92 F. (32-33 C.) degrees, and keep a clear Plexiglas sheet over the tub to retain heat, especially at night. Glass or Saran Wrap works, too. Any of them retards evaporation and helps prevent heat loss. I add a goldfish or two to control mosquitoes, and some underwater grasses to keep the water clear. 

  Any waterproof container deep enough for the aquarium heater works. I once used a tall, deep vase to germinate Victoria seeds, since that was all I was working with at the time. It held two quarts (two liters) of water, and was deep enough to completely submerge the heater. I placed the seeds in a Ziploc bag of water, barely submerged in the vase. This made it easy to remove the bag and check their progress. 

Seeds of Tropical Lilies

Tropical waterlily seeds respond to 90° F (32° C) temperature for promoting fast germination. Please understand that I am talking about TROPICAL waterlily seeds, NOT seeds from hardy lilies! I have no experience germinating hardy lily seeds, but I read that sometimes they germinate while being stored in water in a refrigerator. Hardy waterlily seeds must be kept wet. By contrast, many tropical waterlily seeds can be dried and sprouted later. Hardy waterlily seeds seem to require a period of COLD, wet storage before they germinate. I would not recommend putting them in 90° F (32° C) water until research shows what effects that may yield.

To sprout seeds of tropical waterlilies, place seeds in Ziploc bags of water, along with their name tag. Float the bag of seeds in the hot tub. Examine the seeds weekly. Remove and plant those that germinate sufficiently, and return the remaining dormant seeds to their hot tub for subsequent germination. Not all seeds germinate at once, so practice patience during the germination period that can stretch to six weeks or more.

The seeds of most Australian waterlilies respond to germination in bags of warm water. Their bigger size allows for easier handling than the smaller seedlings of most other tropicals.

If you prefer to plant seeds in soil, cover them with a layer of fine sand. Place the seedling tray into the hot tub to promote faster germination. If you have fish or snails present, employ some method of keeping them away from the seed pan. Otherwise, the fish or snails may eat or dislodge the seedlings as they grow. Use screening or a raised, clear plastic covering over the seed pan to protect against fish and snails. I sometimes use two clear plastic for the soil, the other for a top...and paper clip them together at the rims. Once the seedlings emerge, relocate the seed pan to a sunny pond where with 75-80° F (24-27° C) water where they should progress quite nicely. Their relocation makes more room in your hot tub for more seeds or tubers.


Many tropical waterlily tubers remain viable but dormant for many months...sometimes for several years. Use the hot water treatment to break their dormancy, thereby forcing the tuber into growth. This is particularly useful for getting an early start on the growing season. Many tubers do not begin growth until the pond water consistently maintains a temperature around 85 F. (30 C.). By then, half the growing season may be lost. However, by starting the tubers into growth in March or early April, you gain a significant head start on the growing season.
You can force many Australian waterlily tubers into growth with three or four weeks of hot tub treatment; without this early intervention, these tubers may not sprout until July or August...too late to produce sizeable plants for the current season. Sprout tubers in Ziploc bags of water, or just dump them loose into the hot tub if you are confident you can correctly identify the plants that emerge.
^ Note this photo of Nymphaea immutabilis, forced to sprout in early April, following three weeks of 90° F (32° C) hot tub treatment. The plantlet is ready for removal from its tuber. Pot the plantlet. After a few more weeks in the hot tub, the tuber should produce another plantlet.  

  This spring, I took 20 Victoria 'Longwood' seeds, removed the seed coat at the operculum with a razor blade, and placed the seeds in a sealed plastic sandwich bag of pond water. Then I placed the bag in the hot tub with various dormant waterlily tubers. Within five days, the water in the bag turned tan, because some of the pigments from the cut seed coat leached into the water. Whenever this happens, I change the water in the bag, so it stays clear and makes observation easier. In 15 days, a third of the seeds had sprouted their filiform leaves.   
I like to remove the seeds from the bag at this stage, and plant them. However, other growers wait for the first or even second hastate leaf to form before planting the seeds. The seed contains enough stored food to support these first leaves. However, once some tiny roots appear, I plant the seeds in soil. (See details on the Victoria-Adventure site.) I return non-germinated seeds to their bag of water, and put them back into the hot tub.

Once Victoria seeds germinate, you DO NOT have to keep the young seedlings at hot tub temperature! Plant them in 75-80° F (24-27° C) water with full sunlight, and they grow very nicely. The hot tub temperature simply speeds up the seeds' germination. From the initial 20 seeds I started with, 15 germinated within three weeks, and 11 of those took root and now thrive in six-inch (ten-millimeter) pots. This method typically produces a better than a 50% success rate...not bad for Victoria, which can be difficult to start. I attribute my success to the hot tub!

Finally, I think too many Victoria addicts obsess over the quality of their water, adding chemicals to control algae, or making frequent water changes. A Victoria seedling does not need light to germinate, only warmth; after it shows hastate leaves, then it needs light.
Once a Victoria seedling floats its leaves, it does not care if there are algae in the water! Basking on the water surface, the leaves enjoy all the sunlight they want. Algae indicate an excess of nutrients in the water. This is a GOOD thing, as far as the Victoria seedling is concerned. The Victoria tank photo shows abundant algae growth on the water surface. Note how happy the Victoria seedlings; please leave them alone until they need repotting! 


In summary, it takes heat, not light, to break dormancy of Victoria seeds, tropical waterlily seeds, and tropical tubers. They require light once they produce some leaves, so the hot tub can be small if you remove the sprouted material every week. Keep seeds and tubers that have not started growth (including tubers from which you have removed plants) in the hot tub for further development. So...if you want success in a hurry...don't be afraid to get into some hot water! 

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