Pond Boss Forums AQUATIC VEGETATION Controlling unwanted plants Eradicating water lilies

As you are probably realizing cornmeal will not affect the lily growth. I don't think you will ever be able to adjust the chemical -nutrient balance enough to reduce growth of water lilies. To organically control the water lilies (fragrent or spadderdock type) you are in for a lot of effort.

Repetitively cutting the new growth will in theory eventually cause them to die. But you could be come very frustrated and tired before the lilies completely die out. Any new leaves at the surface are sending food reserves to the roots for future growth. You figure out how often to cut off newly appearing leaves.

The Bad News. Quickest way to organically get rid of them is to drain the pond and scrape out the sediments. This may be the last option for you but it is quick organic removal. Time frame is sometimes important and valuable.

I personally do not see how use of a synthetic herbicide would ever be considered organic.