How do I get rid of horseradish? It is coming up in my flower garden and is completely unwanted.
Digging the root out will help. For portions you miss and that send up leaves later, spot spray with glyphosate (nonselective herbicide). You can use a piece of cardboard or sheet metal as a spray shield to keep the spray from wetting any part of the flowers. Glyphosate is a systemic herbicide and will go down and kill roots. It is not soil active, so there won't be any lingering effects on the flowers.
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