Winter Weeds & Algae01/04/2021 Winter temperatures mean that nothing will grow in your pond, right? Wrong! Even in winter, algae and weeds are capable of growing in your pond. Maintaining your pond throughout the winter allows for better control over growth that will appear in the spring. As algaecides and herbicides near freezing temperatures, they will lose their effectiveness. Most herbicides and algaecides are designed for action above freezing, targeting the plants at their best growing conditions. They are not engineered to function in near freezing conditions and are not designed to be freeze proof. Plant growth and uptake slows down to nearly nothing in freezing temperatures. Due to this, the plant simply picks up too small an amount of chemical to harm it. Rule of thumb is to only use aquatic algaecides or herbicides if the water is 45 degrees Fahrenheit or above. So if you shouldn’t use algaecides or herbicides in freezing temperatures, what does winter pond maintenance look like up north? Adding pond dye and beneficial bacteria will limit the amount of light that penetrates through and lowers nutrient levels in the pond. These products are designed to effectively treat in cooler temperatures. They will not kill any weeds or algae, but they do limit how quickly they can grow in cooler water. Sanco offers three shades of pond dye that will keep your pond clear and beautiful year-round. Crystal Blue, a royal blue dye, settles out dissolved solids and keeps water clear. Similarly Ocean Blue maintains your pond in the same way, but has a turquoise coloration. In contrast, Black Out enhances your ponds natural coloration by creating a mirror-like effect that reflects the surrounding foliage and growth around your pond.