This is one of the most common questions we get from pond owners. Weeds can compromise how we use a pond and make them feel more like a swamp than the swimming hole we want them to be. They can also cause problems with pump intakes, fishing and even basic aesthetics. So how do you manage excessive aquatic plant growth in a pond?
Aquatic plants, just like plants on land, need a few basic elements to thrive, and by limiting these elements we can limit the growth in our ponds. The two main elements that all plants need are light and nutrients. In ponds we address light penetration into the water by adding pond dye. Pond dye essentially creates a highly reflective surface on your pond so that less light reaches the bottom, where plants start to grow every spring. Pond dye works best at depths greater than six feet and will not be as effective in the shallow areas around the edges of your pond. Pond dye works on the premise that plants grow poorly without light, so blocking it will reduce the growth in the main body of the pond. Pond dyes are available in blue, which you commonly see at golf courses, as well as black, which give a more natural Muskoka water look. Pond dyes are most effective if added early in the spring as soon as the ice is off the pond and before plant growth starts. They are non-toxic and safe for humans, pets and wildlife alike so are a very low risk approach. For more information about sizing and dosage please see our pond dye products on page 6.
The other main component that aquatic plants require are nutrients (also called compost, fertilizer, or organic matter). Nutrients in a pond can come from many different sources but on a basic level they are food for plant growth. The nutrients most relevant to plant growth in a pond are the organic matter on the bottom that started out as last year’s plant die off, leaves blowing into the pond or even grass clippings. To manage this nutrient layer, we need two main elements; aeration and probiotics. Aeration provides the oxygen needed to allow nutrients to breakdown aerobically (with oxygen) which is much faster process. We will take a more detailed look at aeration options and the details of how it works on page 14. Essentially by add oxygen into the water we will not only increase the speed of nutrient breakdown but allow probiotic treatments to be more effective as well.
Probiotics target the nutrients that are used for plant growth and accelerates their breakdown while redirecting it into the food chain. The main type of probiotics we use for weed growth addresses the organic matter that accumulates at the bottom of the pond. By using probiotics, we take a natural process and greatly accelerate it so that we can essentially turn back the clock on the aging process of your pond. As a natural process it is extremely safe for pond users, pets and wildlife. This process will take time to accomplish, just as it takes time for a pond deteriorate. It will however, mean that you are not simply dealing with the symptoms of your pond aging but the source of the problem.
