roses

carol.a.ashton

my roses have what look like white aphids on the branches but when brushed off they are powdery, are they harmful and how do I get rid of them. Any assistance would be most appreciated

Obelixx

As long as your roses are healthy they can cope with a few pests until their natural predators come along in the form of birds such as sparrows and tits and/or insects such as ladybirds, lacewings and hoverflies.   Let nature take it's course so a balance is achieved.

If you're worried, try blasting them off with a spray from a hosepipe but do try and avoid chemocals as these areindiscrimnate and also kill the good guys.    You can mulch your roses with well-rotted garden compost and/or manure which will improve soil fertility and thus make healthier plants.  You can add some blood, fish and bone to the mix and water in some liquid rose or tomato fertiliser as an instant tonic.   If we get more heatwaves and prolonged dry spells, keep them watered with at least 15 litres at a time rather than a dribble a day.

gjautos

Are you sure they are aphids? Could it be powdery mildew? Might be worth putting a photo up so people can have a better look for you 

carol.a.ashton

thank you for replies, had a friend visit and he said it was more likely that it is powdery mildew but it is not affecting the leaves so will treat it is as such with homemade insecticide (no chemicals involved). Thank you once again

Obelixx

If it's mildew an insecticide won't work and will harm beneficial predators so don't spray!

Mildew is isually caused by poor cultivation so fix the problem by feeding and watering your rose then giving it a good mulch of well-rotted garden compost and/or manure to make it healthier and pruning it to improve the shape and allow extra ventilation.

carol.a.ashton

Thanks very much for your reply.  The spray does not involve chemicals but I will try what you suggest although it does not seem to have harmed them at all, many thanks again will keep you updated(my friend is no expert it was just his opinion)

Fairygirl

What does the spray contain then? 
If it was mildew it would more than likely be on the foliage, not just stems.
I think it could be a scale insect of some kind, but without a photo, everyone is just guessing.
Guesses are often totally accurate, but @Obelixx is right in saying that spraying something when you don't know what the problem actually is, can do more harm than good. 

carol.a.ashton

Thanks for the comment  not at home at the moment but will post a picture early next week. The home mDe spray is for black spot and not the powdery stuff

Obelixx

You're still spraying the wrong problem with the wrong treatment and badly used fungicides can be as damaging as badly used insecticides.

You'd be far better off improving the plant's health by managing its pruning to open up the sturcture and let air flow and improving the soil fertility aorund it by adding mulches and manure to make it stronger.   Just like healthy people don't catch or quickly fight off common illnesses, so do healthy plants not succumb.

carol.a.ashton

Obelixx I have not sprayed the roses with anything, when I get back home I will take the advice that everyone has been kind enough to offer and I have never used chemicals or fungicides in the garden, so thank you all for your advice