Hydrilla is Florida's most problematic invasive aquatic plant — and Bay County ponds are particularly vulnerable. Here's what you need to know about effective control.
Of all the aquatic plants we manage across Bay County and the Florida Panhandle, hydrilla (Hydrilla verticillata) is the one that most consistently exceeds property owners' expectations for how fast and completely it can take over a water body. A pond that shows only a thin underwater carpet of hydrilla in the spring can be completely choked — surface to bottom — before summer's end. And once established, hydrilla does not respond to the consumer products or seasonal approaches that might partially address other aquatic weeds.
Florida classifies hydrilla as a Prohibited Aquatic Plant. The state's aquatic plant management program spends millions of dollars annually managing hydrilla in public waterways — which gives you some sense of how seriously the problem is taken and how difficult complete eradication is. In private ponds across Bay County, the challenge falls to the landowner, and without professional management, hydrilla typically wins.
Hydrilla's extraordinary resilience comes from its reproductive strategy. It reproduces by four separate mechanisms — stem fragments, seeds, tubers, and turions (dormant buds) — any one of which can produce an entirely new plant. This means that even aggressive mechanical removal or partial herbicide treatment that fails to address all four reproductive pathways will produce regrowth, often in the same season the treatment was applied.
Hydrilla also tolerates low light conditions better than almost any other aquatic plant, allowing it to survive in depths where photosynthesis is marginal for competing species. Once it establishes a dense canopy, it shades out native plants that could otherwise compete with it.
Florida has two genetic biotypes of hydrilla — Monoecious and Dioecious — with slightly different characteristics. The Dioecious biotype is more common in North Florida including the Panhandle region and tends to be more cold-tolerant. Both biotypes respond similarly to management approaches, but understanding which type is present can inform herbicide selection.
Systemic aquatic herbicides are the most effective long-term control method for hydrilla. Fluridone is the most widely used product for hydrilla management in Florida — it works by inhibiting carotenoid biosynthesis, preventing hydrilla from producing the pigments it needs to survive. Fluridone is applied at low concentrations maintained over an extended contact time (60–90 days in slow-moving water), which is why it requires professional application — achieving and maintaining the correct concentration requires careful monitoring and coordination with water inflow and outflow conditions.
For ponds where fluridone's extended contact time is not feasible, endothall and diquat provide faster-acting contact control. These products work quickly but do not address tubers and turions in the sediment, typically requiring multiple treatment cycles across seasons for sustained control.
All aquatic herbicide applications in Florida must be performed by a licensed applicator. Panhandle Pond and Lake Services is a licensed aquatic herbicide applicator, fully compliant with all FDEP regulations.
Our Weedoo TC-12 aquatic weed harvester provides immediate surface clearance for hydrilla infestations — cutting, collecting, and removing large volumes of vegetation in a single operation. Mechanical removal does not address the full root system or the tuber and turion bank in the sediment, but it provides immediate aesthetic improvement and reduces the biomass load that would otherwise die and add to sediment nutrient levels. Mechanical harvesting is most effective when integrated with subsequent herbicide treatment.
The most effective approach combines mechanical removal for immediate surface clearance with targeted herbicide treatment to address root systems and reproductive structures, followed by a monitoring and maintenance program to detect and treat regrowth before it re-establishes. This approach also minimizes the oxygen depletion associated with large-scale hydrilla die-off following herbicide treatment.
Don't wait until it covers your entire water surface. Early intervention is significantly less expensive than emergency treatment of a fully-established infestation. Call us for a free assessment.
Get a Free On-Site AssessmentThe best hydrilla control is preventing introduction in the first place. The most common vector for hydrilla introduction to private ponds in Bay County is boats and trailers that have been used in public waterways with known hydrilla infestations. Before using any boat in a new water body, inspect and remove all vegetation from the hull, prop, trailer, and any equipment that has been submerged. Never transport live aquatic plants of any kind.
Panhandle Pond and Lake Services serves Bay County and all surrounding Panhandle counties. Call (850) 819-9798 for professional hydrilla assessment and treatment.
Related reading: Aquatic Weed Identification Guide — Florida Panhandle | How to Control Aquatic Weeds in Florida Panhandle Ponds