Expert: Long Island Gardener - 7/16/2008

Question
I just finished reading your detailed message on keeping cala lilies healthy and alive. I have a question. I bought a large potted cala lily, yellow in color with lots of blooms still on the stems. Over the past weeks I've noticed that all these blooms are turning greenish. They are still healthy looking but I wonder what has happened to the bright vibrant yellow that originally I thought was stunning. This plant is on my deck in the full sun in Alberta Canada. Zone 3, but we are still having summer weather here. Any advice is appreciated including how to keep this alive during our long winters.

Answer
I admit I have not grown Yellow Callas, but I must tell you that you are not the first person to observe their Yellow Callas turning into Green Callas for no apparent reason.  See the Dade County Coop Extension cheat sheet on Callas:

miami-dade.ifas.ufl.edu/programs/commorn/publications/calla-lily-production.PDF

and I quote: 'As the 'flowers' grow and age, they do not wither and dry out as most flowers do, but remain erect and seemingly fresh as the seeds develop within the spathes.  Their color darkens, taking on tones of Red or GREEN.'

See that?

I lift that language not because I think your Calla is reaching the point of seeding -- it may be, or it my not be -- but as a guide to some of the color changes you can expect from a perfectly Normal Calla.

Note also that in today's plant world, Perennial in commerce does not always mean 'perennial' in Webster's dictionary.  Modern science breeds for profit.

As a result, many so-called perennials are not vigorous enough to return the way they were originally programmed, before we messed up their genes.  The Dade County government plant people warn their fellow Dadeians, 'Seven seasons of trials in S FL have shown that the decid Callas are not garden perennials here.  They grow and flower well, then go dormant, never to be seen again.'

Now, 'dormant', by definition, means 'temporarily out to lunch', not 'permanently out of business'.

But these Callas make people rich.

Calla Lilies are VERY HOT right now.  Keeping a specimen that came from one of those intense Calla-making machines means rescuing a bulb that has been heavily chemicaled up with all kinds of alien hormones and cell-enlargers -- like Giberellic Acid, which artifically expands individual cells the way force-feeding a duck will get you foie gras.  There's a lot of recovering to do after you go through one of those machines.

Much of the time, those mills sap every last ounce of energy to get those plants to bloom so that you or someone who loves you will buy one.  For every horticultural extension scientist studying ways to keep a Calla healthy, there are a dozen scientists studying the effect of chemicals with names as long as a sentence, and hyphens and numbers, on cells, to discover the next patent-worthy plant drug.

I can only guess that the fading is related to age, perfectly normal.  You know, all flowers fade routinely, and when they do, it is a sign that you should remove a faded flower from the plant to prevent it from expending a lot of resources making Seed.

Remember, Color is intended to promote pollination.  It attracts the pollinator.  When the pollinator is out of the picture, figure Mission is Accomplished, Seeds are now in production.

Most flowers lose at least some of their color to strong sunlight.  In the future, you can max out longevity of blooms if you protect them from direct rays and heat.  Also make sure they are not exposed to any kind of ripening fruit or dieing cut flowers; the ethylene gas produced is known to cause fading.

Now let's talk about after-care.

This is REALLY important.  Because this is when new tuber growth takes place.  This is where future flowers begin.  Do this right, and next year will be its prettiest possible self.

Colored Callas as you may know are planted in the Spring for Summer bloom.  They're NOT hardy in your climate, but you can certainly give them the care they need to survive and bloom in the future.  Just dig them up and keep them cool, dry and dark.  DO NOT store in a plastic bag (no air).  Any time between 10 weeks and 10 months later, plant them back in the pot, and grow as usual.

One more thing.

These do not last forever, not even with the best scientific care.

Your heirs will not be inheriting their grandmother's Calla tubers.  In fact, you won't even be growing this in 10 years.  Callas are created for beauty and profit.  Not for longevity.  That's capitalism for you.  Out with the old, in with the new.  Thanks for writing.

THE LONG ISLAND GARDENER