Valdor® Flex is a herbicide that controls a broad spectrum of weeds. When applied prior to germination, Valdor® Flex keeps the soil weed-free for up to 4 months by creating a dual barrier at the soil surface. The 2 active ingredients, Iodosulfuron and Diflufenican, complement each other and improve the result compared to applying the active ingredients individually. Utilising the latest generation of water dispersible granule (WG) formulation, Valdor® Flex quickly dissolves in water and stays stable in the tank for a minimum of 24 hours.


Valdor® Flex is best applied before the emergence of weeds. Valdor® Flex can be applied all year round (ground weather conditions permitting), with a single application per year.

  • Apply before weed emergence

  • For post weed emergence, tank mix with glyphosate or fatty acids


Valdor® Flex can be applied to all permeable surfaces and railway ballast to provide effective weed control in a number of environments from industrial sites to public spaces. If weeds are present Valdor® Flex can be applied with glyphosate or a fatty acid to achieve control of existing vegetation.

Non-crop areas (permeable surfaces overlying soil) such as: gravel paths and driveways, porous surfaces alongside roadways and fence lines, porous strips of land adjacent to buildings, industrial sites, timber yards, farm yards, oil and gas storage sites, power stations, electric sub-stations, beneath pylons, around street/park obstacles and furniture, porous areas near to trees and shrubs and other natural surfaces where vegetation is not desirable, and railway ballast.


These active ingredients complement each other and improve the result compared to being applied individually. Valdor® Flex controls a broad spectrum of annual and perennial broad-leaved weeds and grasses on natural surfaces not intended to bear vegetation, permeable surfaces overlying soil, and hard surfaces (railway ballast only) and amenity vegetation (around). It can be applied once per year at a rate of 0.5 kg/ha.


Check and calibrate the sprayer, before starting treatment. To prevent a surplus of spray fluid, Carefully measure the surface to be treated and accurately calculate the required amount of spray fluid.

Proceed as follows:

  • Fill half of the spray tank with water

  • Add the required amount of Valdor® Flex to the spray tank

  • Agitate before use

  • Top-up water to required amount


Example post emergent treatment programmes

Using Valdor® Flex as part of your weed management programme will provide cleaner surfaces for longer, while also reducing the amount of applications and active ingredient used when compared to a traditional weed management programme.

Dual barrier to prevent weed emergence

Formulation of Valdor® Flex

Valdor® Flex uses the latest generation of wettable granule (WG)

  • Very low dust formulation reducing operator exposure

  • Very stable as a suspension in the spray tank

  • The granules dissolve quickly and remain in suspension for a minimum of 24 hours

  • Product does not deposit on the bottom of the tank at time of mixing

  • Low odour

  • No stains on treated surfaces

Available in:

500g bottles (1ha) for large areas and safe and easy tank filling

Convenient 10g sachets (200m2) ideal for knapsack use

MAPP 19033

Active Substance: 360 g/kg diflufenican, 10 g/kg iodosulfuron-methyl-sodium.

Key weeds controlled by Valdor® Flex supported by internal trials:

  • Plantago lanceolate (Ribwort Plantain)

  • Solanum nigrum (Black Nightshade)

  • Veronica persica (Persian Speedwell)

  • Sonchus asper (Spiny Sowthistle)

  • Picris echioides (Bristly Oxtongue)

  • Trifolium repens (White Clover)

  • Epilobium parviflorum (Hoary Willowherb)

  • Poa annua (Annual Meadow Grass)

  • Daucus carota (Wild Carrot)

  • Geranium dissectum (Cut-Leaved Crane’s-bill)

  • Taraxacum officinale (Common Dandelion)

  • Medicago lupulina (Black Medic)

Application and stewardship tips

  • Do not apply Valdor® Flex in groundwater protection areas

  • To minimise spray drift, the product must be applied using a nozzle capable of producing a coarse quality spray (e.g. Hypro Polijet AN0.6 or equivalent), or a track dedicated low drift application system.

  • This product must not be applied to any non-porous surface

  • Only apply during suitable weather conditions

Application permitted using:

- Handheld sprayer

- Vehicle mounted boom sprayer

- Track dedicated low drift system for rail

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