Sorry, I grow in the UK and didn't check the location of the OP (Pensylvania). I have also been led to understand that trade in Water Hyacinth is banned in many US States, as well as possession in a couple.
Hi Rob, Water Hyacinth isn't indigenous to your side of the pond either. If I am not mistaken, you all have had your fair share of problems with this plant "escaping" too. The plant is so darn pretty and so darn functional (great nitrate uptake factory) that people freely trade it amongst themselves and drive across state boundaries to purchase it from road side stands and nurseries where it is still legal. This plant reproduces at such a rapid rate that people who can't pass it on to others think nothing of tossing it in composters. The compost obviously gets used at some point in time and we all know the seed of this monster is viable for years. This does not include people who have no knowledge what so ever of this plant’s "attributes" who have "seeded" inland bodies of water. *There are hundreds of examples over here where people were unwilling to bag up and throw out their excess Water Hyacinth so they placed their plants in local ponds and lakes in a misguided attempt to “beautify” the area. These ponds and lakes are generally connected to streams and such that obviously flow somewhere so the plant ends up down stream where it infests other watersheds. Recent hurricane activity in our southeastern states proved that Water Hyacinth could be transferred to other inland bodies of water where it flourished. So much for all the people who claimed they could keep it under control in their backyards. Our government hasn't done the greatest job educating the public. The information is out there but you sometimes have to dig for it so don't feel bad about having suggested it. I hate to do this but I have to admit that I used to have it in one of my ponds. It was given to me by a friend's Mother In Law who had “extra”. The pond was in full sun so it grew well, very well. As mine multiplied, I diligently removed and composted the excess. I had no idea what a beast this was even in states where it doesn’t overwinter until I sent a photo of my front pond where my beloved Water Hyacinth was growing to another friend (Biologist) who told me to get rid of it fast before it ended up in one of the natural ponds because of all the heron around here. Embarrassing is about all I can say however I enjoyed crystal clear water for one entire season using no mechanical filtration.
Has anyone seen Cornell University's Pimental Report from a few years ago?
This might prove interesting reading-
Didn't know that about the seeds. Interesting. The UK has never had a problem with the plant, though I don't know about further south into warmer parts of Europe. Mine has never flowered in the UK in the few years I have been using it - prob too cold despite being in a greenhouse. In fact the plant this year has been so efficient at starving the water that it is very weedy in my utric tanks this year! Half it's normal size and showing no signs of making all those offshoots. Might pop some more back into my brother's pond to get some divisions of it up and ready for next year's season.
*does a google image search* Ohhh! My mom bought one of them for the mini pond last year! It never flowered but I thought it was a neat little thing. It must not be illegal here cuz she bought it from a pretty popular aquarium/petshop place. Anyways, I'm pretty sure it has become dead by now, it's got water but no sunlight. The weeds completely ate the pond. It's more or less just like a trap door now. You try and walk on the weeds and fall in a small pool of water. xD I should trick someone with that.... hmmm... *starts devising a plan*...
...wow look how far off subject I've gotten!...*click*