Plant Doctor Archive

 I HAVE a garden that has been neglected for a number of years and is smothered with onion weed and oxalis (a fine white flower type). Is there a spray or sprays that I could use?

 I ASKED one of our horticulture lecturers, Reg Lewthwaite, for his suggestions.

For onion weed, Reg suggests that you try glyphosate. This will also (temporarily) kill grasses, so you should try to paint or wipe it onto the onion weed leaves.

As for oxalis, Reg notes that there are a number of types of oxalis, and some information indicates that some agrichemicals work better than others. Reg uses glyphosate on the leaves, which kills off the tops, but leaves the bulbs behind to remove by hand. You can also repeat the treatment on any new leaves which emerge.

Other possible sprays include: Foresite 380; Grazon (for creeping oxalis in turf), Ronstar DG, Rout Ornamental, Tordon Brushkiller and clopyralid (Versatill).

As always with sprays, carefully follow the safety and application instructions.

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• Content or advice may be out-of-date.