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One preemergence application controls weeds all season long.

One preemergence application controls weeds all season long.

Ronstar® herbicide controls weeds through shoots, not roots. Unlike competitive products that don't distinguish between roots of weeds and roots of desirable plants, Ronstar doesn't harm healthy turf.

  • Works on warm- and cool-season grasses and landscape ornamentals
  • Can be used before or after sprigging
  • Doesn't inhibit turf root growth or recovery from damage
  • Doesn't prevent roots from tacking down
  • Can be applied to both newly transplanted and established ornamentals
  • Can be applied to woody ornamental shrubs, vines, trees and conifer nurseries
Weeds controlled

Grassy weeds
Annual bluegrass, crabgrass, fall panicum, goosegrass, green foxtail and wild oats

Broadleaf weeds
Bittergrass, bristly oxtongue, carpetweed, cheeseweed, common groundsel, common purslane, evening primrose ragwort, lambsquarters, liverwort, oxalis, Pennsylvania smartweed, petty spurge, prostrate spurge, redroot pigweed, sow thistle, speedwell, spotted catsear, swinecress and yellow woodsorrel

Please see the product label for a full list of weeds.


Frequently Asked Questions

What are the key features of Ronstar G?

The mode of action of Ronstar G doesn’t inhibit root growth, making it ideal for new transplants and liners. It controls both annual broadleaves and grasses including bittercress, groundsel, oxalis, spurge and liverwort.

What are the key benefits of Ronstar G?

Ronstar G controls weeds, not roots. It is labeled for use on over 250 ornamental species with strong performance on several difficult-to-control weeds.

What is the active ingredient?

The active ingredient oxadiazon, is active on shoots, not roots, unlike most preemergence herbicides on the market today.

Where can Ronstar G be applied?

Ronstar G can be applied to containers and field-grown ornamentals, liners, groundcovers, perennials, woody ornamentals, shrubs, vines, trees and conifer nurseries.

Can I use Ronstar G on a wide variety of plants?

Ronstar G is labeled for use on over 250 ornamental plants. Its mode of action inhibits shoot growth, not root growth, making it a great rotational tool for weed management programs.

How long will the effects last?

Ronstar G can last between 2-3 months depending on environmental conditions and the time of application.
Ronstar FLO Logo

Selective, preemergence herbicide for control of grasses and broadleaf weeds

Specticle FLO Logo

Broad-spectrum control of grassy weeds and more than 60 broadleaf weeds

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