Spray larger common tansy plants with a glyphosate-based herbicide before they form flowering seed heads, thoroughly moistening each target plant’s foliage with the herbicide. Herbicide chemicals can cause skin or eye irritation.

How do I get rid of common tansy?

Spot spraying may be an option for patchy infestations. Spot spraying with a non-selective herbicide such as glyphosate will kill tansy, but you’ll lose all of the plants surrounding the tansy leaving a sunny opening conducive to tansy seed germination.

What spray kills ragwort?

Barrier H is a weed killer herbicide that will destroy ragwort at all stages of growth and any time of year. Larger plants, especially flowering plants will require more Barrier H and it is important to cover the whole of the plant. 5L of Barrier H could be enough to treat up to 1600 tiny seedlings.