What is Blanket Weed?
Blanket weed is a type of algae, scientifically called filamentous algae. It’s also commonly known as string algae or silk weed. Pond owners often struggle to identify blanket weed because it occurs in different forms.
Typically, it appears either floating on top of or submerged within pond water as clumps of thick green, hair-like strands. These dense clumps have no leaves, stems or roots but will attach themselves to pond walls.
Ornamental ponds with high sunlight exposure and organic nutrients create the perfect environment for it to thrive.
Not sure if you have blanket weed?
Watch this video:
5 Pond Problems Caused by Blanket Weed
- 1. Aesthetics. Blanket weed ruins the appearance of a pond.
- 2. Not only does it make ponds unappealing, it’s often a sign of chemical imbalance in the pond. (Yes, even if the water looks clear!)
- 3. It consumes large amounts of oxygen from pond water. This creates a harmful environment because aquatic plants and fish are forced to compete with it for oxygen. Especially in summer, when pond oxygen levels are low.
- 4. Floating blanket weed deprives submerged oxygenating pond plants of sunlight. Preventing their process of photosynthesis and further reducing pond oxygen levels.
- 5. Fish can get tangled in submerged string algae. When unable to escape, fish can potentially suffocate and die.
What causes blanket weed?
It has two main causes, excessive sunlight and nutrients. Nutrients in pond water, caused by the build-up of organic matter, act as a food source. While sunlight stimulates growth through the process of photosynthesis. These two factors also the reason it is often a recurring problem.