I noticed one of my many elephant ear plants, (and also my smallest) Colocasia esculenta var. Illustris is what I'm pretty sure it is. It's definitely a colo. It started growing this. This picture was taken yesterday and already today the spathe is open and reflexing. I couldn't find much practical information on pollinating any aroids, especially Colocasia, but I read a lot of technical information, most of which I already knew from the research I made before acquiring these plants a few years ago. That day the picture was taken, I went to every nursery in town and out of six, I found one colocasia plant in bloom. It looks like it will open tomorrow or the next day.

How do I go about cross pollinating these? The newer plant has one larger, nearly open inflorescence, and another one starting to form. Are the two plants blooming to close together in time to pollinate? I know they reach male anthesis and female anthesis at different times to prevent selfing, but I don't even know what comes first (though from pollinating other, less tricky plants I'm guessing male), or how to tell when they reach the times. When do I need to pollinate and how do I do it. If I need to, tomorrow I can take a picture of the second plant. It's a blue, purple color with a yellow inflorescence with a red base, really need looking.

Please help!
Andrew

Blooms on Aroids in general are female-receptive first, then later (next day) the pollen drops. So in your case, you need to look for pollen on the bloom that opened first, and then save and/or use it on the second bloom when it opens. Here is where the trickiness comes in - I haven't done any crosses using Colocasia but in my experience with other aroids, some are receptive in the early evening, some in late evening, some in early morning and some in later morning. I don't know when Colocasia is female receptive, so you will have to check frequently when the bloom begins to open, especially to see if there is a fragrance emitted and if the spadix gets warm. Both of those are signs of female receptivity. Often the period of receptivity is short, being just an hour or two, so timing is of the essence.

Good luck,
LariAnn
Aroidia Research

How do I get the pollen into the closed part of the spathe where the female part of the spadix is?

You'll need to cut away (carefully) a portion of the spathe that is covering the female flowers. I use a scalpel but whatever you use, be careful to avoid cutting into the female blooms.

LariAnn

Hi Andrew,
Good luck and please let us know how it turns out.

I couldn't get the picture to turn out very well, but it looks like it's pollinated! The female flowers are enlargening

Good news Andrew. In you're photograph it looks like the inflorescence is rising from a petiole with an uncharacteristic zig-zag bend in it. Is that correct?

Yes, when I first saw that I thought it was typical for all petioles with an inflorescence following, but the other two I have seen don't have it. Ever seen one before?

No, I haven't Andrew. The only Colocasia to bloom for me is a gigantea. We don't have a photo in the DB and I only found a few on other sites and it's hard to tell from them.
http://www.pacificbulbsociety....
http://www.flickr.com/photos/r...