They are not Illegal in NY and most other northern states due to the die off that happens when it gets even close to freezing temperatures. They readily sell them in most water garden stores for about $1.50 per plant.

They do not pose a risk to waterways up norh due to the frost and cold temperatures.


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1/10 - 1/4 acre pond plus 16 ft deep/ Plus 40 ft by 20 ft by 6 ft deep koi and fathead minnow pond next to it. Upstate NY