Plant Doctor Archive

Onion weed and oxalis

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 glycophosphate. 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 glycophosphate 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 Cloropyralid (Versatill).

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

Advice by Dr Dan Blanchon from Unitec's Diploma in Sustainable Horticulture and Bachelor of Resource Management.

Reproduced with permission from NZOOM Home and Garden content, from the previous website of  The views expressed here are not necessarily those of the RNZIH   HOME AND GARDEN   Plant Doctor Archives Main Page