Always a difficult one! For most of the year you need to spray every two weeks, mostly as a preventative spray. Different pests and diseases appear at different time of year, so the pesticides used will differ. It would be impossible to list every possible pest or disease which may affect your roses, so we have given a list of the commonest ones, and their remedies.
Bollworm – Ludwig’s Insect Spray plus Pyrol OR Asadirachtin = Bioneem.
C.M.R./Flower Beetles or Fruit Chafer – A direct contact spray of natural pyrethrins (add a wetter to this) OR Hand Picking (Wear gloves when doing this!)
Chafer Beetles – As for C.M.R – apply just after sunset when they appear. OR you can use a light trap – hang a light somewhere near the roses, suspended over a large basin or old bath of water with a little paraffin or cooking oil poured on – switch light on at dusk, off in the morning. (Make sure you use a proper outdoor fitting!)
Aphid – Ludwig’ Insect Spray, Pyrol, Vegol, Margaret Robert’s Organivc Insecticide or Bioneed. You can also spray with soapy water – 5ml. dishwashing liquid in 1 litre water.
Thrips – Can appear all year, more in hot, dry conditions. Spray with Canola Oil and/or natural pyrethrins.
Mites – The commonest are red spider mites and two-spotted spider mite. They are very tiny and difficult to see with the naked eye! Hot dry weather exacerbates the problem. Regular wetting of the underside of the leaves helps tremendously. Spray with Ludwig’s Rose Spider Mite spray, Margaret Robert’s Organic Insecticide and Vegol, OR Bioneem.
Powdery Mildew – New young, soft growth is more susceptible (don’t overfeed with too much nitrogen). The old remedy (which still works) is Sulphur. Use Kanguard 94 or Margaret Robert’s Organic Fungicide. Start spraying at the first sign of infection, before it gets a hold.
Black Spot – Climatic conditions play a big part in the appearance of Black Spot. Hot and humid weather brings it along! Spray with fungicides containing copper as a preventative measure when conditions are right for its formation.
What To Expect In Which Month
Each month different pests or diseases can appear – Just a short list of what to look for through the different months of the year.
January
- Black Spot
- Beetles
- Boll Worm
- Red Spider Mite
February -April
- Black Spot
- Beetles
- Boll Worm
May – June
- Mainly Black Spot
July
Spray bare stems after pruning to kill insect eggs and fungus spores.
August]Spray bare stems after pruning to kill insect eggs and fungus spores.
September
- Aphids
- Thrips
- Boll Worm
- Powdery Mildew
October
Powdery Mildew
- Beetles
- Boll Worm
November
- Aphids
- Powdery Mildew
- Beetles
- Boll Worm
- Black Spot
- Spider Mite
December
- Aphids
- Powdery Mildew
- Beetles
- Boll Worm
- Black Spot
- Spider Mite
