Don't Treat Your Algae Too Early

When a mild winter occurs, algae can begin appearing on the bottom and surface of your pond.  This can lead to the desire to treat the algae, even when the water temperatures are very close to freezing!

What one needs to realize is that no matter what you do to a pond and no matter what kind of conditions the pond water is experiencing, algae will grow.  If there is water, there will be some algae growth, with very few exceptions.  Winter temperatures may slow the growth, but it will still occur.  Keep in mind that there are algae colonies that persist in the subzero conditions of the Arctic!  It is a very aggressive and persistent plant that can live in every temperature zone that nature provides.

That being said, algal growth under the freezing conditions usually experienced in northern Indiana in the winter is usually limited due to snow covering the ice and darkening the water.  However, this algae is still present and will appear once the sun is available and allows the algae to produce enough oxygen in order to lift itself from the depths of the pond. 

Pond dyes can aid in limiting how much of the pond is available to the algae, but it will not limit shallow areas from producing algal growth.

During a mild winter, algae have a better opportunity to grow, due to the greater amount of sunlight available because of the minimum ice coverage on hand.  This will allow algal colonies to break free earlier and become noticeable as mats in January and February.  Refreezing of the mats does not harm the algae; it will survive and thrive once conditions improve.

It is important to know that the algae are growing very slowly in conditions below 40°F.  If one treats algae with copper products before the water temps reach 40°F, then the copper will not be utilized adequately by the algae, and it will survive the treatment.