Plant Doctor Archive

Spider mite on roses - 1

I have a problem this year with spider mite on my patio roses. I can't see any mites, but the webs are all over the underside of leaves and the leaves have gone discoloured and are dropping. What is the best spray to deal with this? I dusted them with a powder that said was for mite and mildew, but it hasn't helped much.

Yes, it sounds like a bad infestation of mites. Spray with either Super Shield, Mavrik or Mite Killer at 14 day intervals until there are no signs of any mites. Alternate the sprays so that there is no chance of resistance building up. Pick up any fallen leaves around the rose to prevent over-wintering eggs remaining in the soil.

In winter, spray with Conqueror Oil as a preventative measure to catch any eggs or mites that may still be on the plant.

Make sure your rose is well watered and fertilise regularly with rose fertiliser or Osmcote. A good watering and feeding regime helps the plant build up natural resistance to pests and diseases.

Throughout spring and summer the occassional foliar or liquid feed will also benefit your roses.

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

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