Professional non-chemical weed control

Thermal Weed Management

Compare hot air, hot water and electric systems according to weed maturity, root structure, surface construction, access, utilities, carrier availability and the output required.

Explore thermal ranges Choose a method
3 methodshot air, hot water and electro-thermal treatment
13 range familieshandheld, pedestrian, tractor and vehicle systems
76–80°Cleaf tissue damage begins below visible charring
Year-roundno spray drift and useful wet-weather capability

Choose the heat-transfer method

Three ways to create damaging heat in the plant

All three methods rely on heat damage, but the heat reaches the plant differently: externally through hot air or hot water, or internally when electrical current passes through plant tissue. The practical choice depends on root depth, surface, access, safety controls and route logistics.

Ripagreen Easy Plus hot air weed-control kit

Directed hot air

A fast, water-free route for young annual weeds, moss, path edges, street furniture, bunkers and other targeted work.

  • Portable lance, wheeled hood and vehicle-mounted formats.
  • Propane supplies the heat; Ripagreen mixes approximately 94% ambient air with 6% gas.
  • Most effective when growth is young and detritus has already been removed.
  • Less heat penetration below the surface than hot water.
Eco Weedkiller Pro SP hot water weed-control unit

Hot water

A contact treatment that transfers heat into plant tissue and the upper soil profile, with stored-energy and on-demand systems for different work patterns.

  • 25, 150, 300 and 600 litre stored-water systems are available.
  • Pro SP models are nearly silent during treatment because the water is heated before use.
  • On-demand Pro systems support continuous refilling and higher daily output.
  • Typical planning allowance is 2–2.5 litres per square metre at full vegetation cover.
Zasso Zap electro-thermal walk-behind weeder

Electro-thermal treatment

Electrical current passes through the plant and creates resistive heat inside the tissue, damaging the vascular structure from within rather than heating only the exposed surface.

  • Walk-behind surface-contact, handheld lance and tractor-mounted formats.
  • Useful where heat needs to act through the plant structure and toward the root zone.
  • No flame, hot-air plume or water tank at the treatment point.
  • Requires trained operators, controlled exclusion zones and electrical safety procedures.

Hot-air ranges

Portable lances, pedestrian hoods and vehicle systems

Select the range around access, working width, gas-cylinder logistics and whether the operator works independently or from a support vehicle.

View the complete hot-air range →

Hot-water ranges

Stored-energy and on-demand water systems

Select the family around tank capacity, available charging supply, route length, refill strategy, operator count and whether pressure washing is also required.

View the complete hot-water range →

Electro-thermal ranges

Surface-contact, lance and tractor-mounted electrical systems

Select the range around treatment width, root depth, access, carrier capacity, generator output and the level of reach required. Electrical current is the delivery mechanism; heat generated inside the plant is the mode of action.

View the complete electric range →

Thermal method finder

Start with the site rather than the machine

Use three operating conditions to identify the most suitable hot-air, hot-water or electric range family. The result is a starting point for a demonstration and site assessment.

Technical planning factors

Thermal output depends on preparation and timing

The machine is only one part of the programme. These operating factors have a direct effect on treatment speed, repeat visits and consumable use.

Remove detritus first

Soil, leaf litter and organic debris support new germination and can shield plant tissue. Sweeping or mechanical removal improves visibility and reduces fire risk before hot-air work.

Treat early growth

Young, fleshy plants have less stored energy and normally require less heat than mature woody growth. Plan repeat visits around emergence rather than waiting for full establishment.

Do not chase charring

The target is rapid heat transfer into plant tissue, not burning the leaf black. Excess dwell time reduces output and can increase surface or fire risk.

Plan water by green area

For hot water, estimate the actively vegetated square metres rather than the total route area. Full-cover treatment typically requires about 2–2.5 litres per square metre.

Match the work pattern

Stored hot water suits stop-start and noise-sensitive work. On-demand systems suit long shifts and refilling. Hot air avoids water transport, while electric systems require generator capacity, electrical controls and trained operators.

Control heat hazards

Assess dry combustible material, LPG handling, scalding, electrical exclusion distances, buried or overhead services, public access, thin plastics and reflected heat. Use trained operators and the controls required by the site assessment.

Integrated Weed Management

Thermal treatment works best after the growth medium is addressed

Use sweeping, edging or renovation to remove accumulated soil and detritus, then use thermal systems on the smaller annual weeds and moss that re-emerge. This changes the workload from repeated clearance of established growth to planned treatment of early growth.

Explore mechanical preparationView the Bracknell trial

Range and support links

Move from method selection to a working specification

Hot-air weedersBrowse Ripagreen and HOAF handheld, pedestrian and mounted systems.View hot-air ranges → Hot-water weedersBrowse Garden, Pro SP and on-demand Eco Weedkiller systems.View hot-water ranges → Electro-thermal weedersBrowse pedestrian, lance and tractor-mounted systems that generate damaging heat inside the plant.View electric ranges → Bracknell IWM trialReview site diagnosis, intervention planning and measured programme results.Read the trial → Book a demonstrationTest treatment speed, access and handling on a representative site.Arrange a demonstration → Talk to a specialistSend the site type, weed mix, route length and available carrier or utilities.Contact Kersten →

Frequently asked questions

Thermal treatment in practice

Does the weed need to turn brown or char during treatment?

No. The objective is to transfer enough heat to damage the plant cells and stop photosynthesis. Visible charring usually indicates unnecessary dwell time.

Which thermal method has more effect below the surface?

Hot water conducts heat into the upper soil profile, while electrical current can generate heat through the plant structure and toward the root zone. Hot air is strongest on exposed young annual growth and moss, especially after soil and detritus have been removed.

Why is electric weeding included as thermal weed management?

The electrical current is the delivery mechanism, but its practical mode of action is heat generated inside the plant. That internal heating damages chlorophyll, vascular tissue and plant structure without applying an external flame or water jet.

Can thermal systems be used in wet or windy weather?

They are not affected by spray drift in the same way as herbicides and can remain useful in wet weather. Operators must still control the hot-air plume or water jet safely and stop work when site conditions make that impractical.

How should I choose between stored and on-demand hot water?

Stored-energy Pro SP systems suit quiet, stop-start routes and can retain working temperature for many hours. On-demand Pro systems suit longer shifts, continuous refilling, multiple operators and combined cleaning tasks.

How much hot water should be allowed for treatment?

A practical planning allowance is around 2–2.5 litres per square metre where vegetation covers the complete surface. Actual use varies with plant size, density, weather and operator technique.

Is thermal treatment a one-pass permanent solution?

No weed-control method removes the need for monitoring. Thermal treatment is most efficient when used early and repeated as required within an integrated programme that also reduces the soil and detritus available for new weeds.

Specify the route before the machine

Bring the surface, weed mix and logistics to a demonstration

Kersten can compare hot air, hot water and electro-thermal treatment on a representative area and help define tank capacity, gas or electrical supply, voltage, working width, hose or arm reach, carrier and treatment frequency.

Book a demonstrationTalk to a specialist

Frequently Asked Questions

Thermal weed management works by briefly exposing plant leaves to a temperature of around 80°C. This intense heat causes the cells in the plant leaf to burst, rendering the plant incapable of converting light energy into chemical energy (photosynthesis). This effectively causes the plant to starve, leading to its demise. Visible scorching is not required for terminal damage.

Thermal weed management is most effective on young, fleshy, hungry plants. It is less effective on old, established woody plants, as they may have sufficient amounts of stored energy in their stems and roots to overcome temporary food shortages caused by the thermal treatment. The method targets the plant's ability to photosynthesize.

No, it is a common misconception that a plant must be visibly scorched to suffer. A plant leaf only needs to be briefly exposed to a temperature of approximately 80°C to sustain terminal damage. This exposure bursts the cells in the leaf, preventing the plant from performing photosynthesis and ultimately leading to its starvation.

Kersten offers various thermal weed management solutions including Ripagreen Thermal Lances, Hoaf Weed Burners, Eco Weedkiller Hot Water systems, and Electric Weeding Equipment. These solutions utilize either hot water or hot air techniques to effectively manage and control unwanted plant growth on different surfaces and in various applications.

Yes, hot air is likely the most ecological thermal weed control method. This technique, along with hot water, offers an environmentally friendly alternative to traditional inorganic chemicals for managing weeds. It works by damaging plant cells with heat, thus stopping photosynthesis and leading to the plant's eventual starvation without chemical intervention.