waterlily question

[andi_mn]

me again...wondering...since waterlilies Live in dirt and water, why do they sometimes rot?

[Vickie]

I loose lilies too but there is  something called crown rot. I think it only affects hardy lilies. Don't panic you probably don't have it. But here is what it says.

Crown rot is the main water lily killer, first turning leaves yellow and diminishing flowering. It is very contagious. Lift your plant and remove any healthy-looking sections of rhizome. Wash and replant these, then quarantine them in a holding tub until you know that they are disease-free.

[karen J]

There are a lot of different kinds of rot as well- crown rot being the most recognizable. I don't want to sound pessimistic, so the optimistic thing to say is that there are ways that lilies protect themselves from rot & fungus. Kind of like a human adaptive immune system, it can't be reduced to NPK. Good dirt, good water quality, good sunlight, enough (not too much) fertilizer, micro-nutrients, etc.
Which brings the question- Why the rot? Can you describe it? Is there a waterfall nearby?

[turtlemike]

  Do you mean the leaves or the rhizome ? 

  The leaves always "rot" this time of year as the plant goes dormant. Some lilies with mexicana in their heritage never fully go dormant and will have leaves and buds all winter just below the ice. Others will lose all of their leaves and buds except some small leaves that look like lettuce that cluster around the crown all winter. That is true dormancy.

 Someone told me that those leaves were called indicator leaves because the plant uses them to sence the lengthing days of spring to know when to start growing.  Has anyone else heard this or is there other ideas about this.  Do these leaves provide food nessary for surviving a long winter? What happens if you remove them?  Are they just the result of dormancy hormones stunting the last leaves of the year as the plant enters full dormancy but serve no funtion?  The later is what I tend to believe.  I am speaking of hardies of course.

[emm]

The only lily that I regularly have problems with rotten rhizomes is Nymphaea 'Colorado'.  After trimming off the rotten bits in the spring there is sometimes very little rhizome left (2") but it always rallies and is in full bloom with multiple blooms daily by July.  I wonder if it is just barely hardy where I live in Ontario, Canada.  I believe that one of its parents is N. Mexicana which I think prefers the warmer temperatures.

emm

[turtlemike]

  That sounds possible.
I don't know what a lily that is planted too far north acts like. As long as it doesn't freeze the only other thing I can think of that would make it die is it starving before spring.