Black spot on roses

All this wet warm weather, grrrrr. Anyone remember if Is it trim milk or baking soda I can use on them please! Otherwise I have Conqueror oil in the shed, can I use that. TIA.

Bump.I would be interested to know as well

this arises every year. put your title as posted into little box on the top right, and select 'last year'.there may be some answers you like.

I'd already done that wheelz, thanks. Couldn't find anything.

excellent info for afflicted roses

Fungal disease
There are three main fungal diseases that affect roses - mildew, black spot and rust. The spores of fungal disease carry over from season to season on the soil, and the removal of fallen leaves is important in reducing the incidence of fungal disease.

Healthy roses and some specific rose varieties are less susceptible to fungal diseases, so feed your roses.

Water, regular watering, is one of the most important things you can do for you roses as when they are dry and stressed they are far more vulnerable to disease.

Good garden hygiene such as removing litter, prunings and fallen foliage will help to prevent a build up of sites that encourage fungal disease.

If you have rose that is affected by fungal disease year after year, it is worth considering taking it out. Regular spraying can help to reduce fungal diseases. Organic gardeners need to seek more resistant varieties and avoid the highly bred roses such as hybrid teas and some modern roses.
Mildew is a powdery white substance that forms on leaves. Good air circulation helps to avoid this, but in warm, wet climates sometimes nothing seems to help.
Black Spot is dark spotting or 'splodges' on rose leaves and removing the affected leaves (including any on the ground) and burning them is essential.
Rust shows as rusty spots on the leaves, most obvious on the undersides of the leaves. Remove any leaves, including fallen leaves, and burn them.

Blackspot, "Diplocarpon rosae", is a nasty fungus that manifests itself on rose bushes as black spots on leaves progressing to black spots fringed with yellow rings on both sides of the leaves. As they develop the spots enlarge. Eventually, as the disease spreads, the entire leaves will go from green to yellow and then drop to the ground. With time the entire rose bush may become defoliated. Leaves less than two weeks old are the most susceptible to this disease.

Defoliation brought on by blackspot is worst during wet weather, especially humid weather. The fungus becomes active in a wet environment with a temperature of about 24 degrees Celsius (approximately 75 degrees Fahrenheit). It needs about 7 hours of these conditions to germinate and then symptoms will begin to appear on rose foliage within three to ten days. From then on spores are produced every three weeks. If unchecked, blackspot can affect the entire rose garden leaving an unattractive appearance of many ???bare-naked??

Black spot is the main fungal disease that affects roses but it also likes fruit trees such as apples and pears. It is brought on by wet, humid conditions in spring and summer. The spores are spread by rain splash and overhead irrigation.

Again, black spot is host specific. The black spot (also called apple scab) that affects apples is different to the one that affects roses.

You can control it by spraying with a copper-based fungicide, ideally starting in spring as the weather warms up. You can start spraying now, though, to prevent further spreading (it won't cure it). Continue spraying at 14-day intervals.

Kiwicare Organic Copper Oxy is perfect for this and it works on vegetables, fruit trees, ornamentals and roses.

Any infected leaves that fall to the ground should be picked up and binned, otherwise the spores will over-winter and reinfect plants next spring.

US-based website Gold Harvest Organics recommend a cider vinegar solution for control of black spot and mildew. Mix 3 tablespoons of cider vinegar with 1 litre of water and spray on infected plants.

A gardening friend regularly sprays her roses with a liquid seaweed fertiliser and swears this reduces fungal problems as well as pests.

Organic spray for blackspot on Roses
In a 10litre bucket of water add 5 tablespoons of baking soda and a couple of splashes of compost tea or worm farm liquid and a dash of washing up liquid. Mix thoroughly and spray weekly.

My roses have NEVER been so good. This year I have fed them well, mulched them thickly, deheaded as required & sprayed with one of the following recipes almost after every rain! According to whim i choose from:
3 Tbsp Apple Cider ( or any vinegar) to 5 Litres water
or
Full cream milk (I bought powder to make up), 1 part milk to 7 parts water
or
1 Tbsp vinegar with 2 L water & add 1tsp baking soda 1 tsp vege oil.
At any time, esp if plants need a kick, add liquid seaweed or fish emulsion to whichever mix you're using, say 1/2 tsp / 450ml of spray mix.

The best thing with these mixes is it won't hurt you or the bees so you don't have to wait for wind to die down or remove flowers first. Also the mixes can have pyrethrum (natural) to kill aphids- which have been almost non existent on mine this season, perhaps due to the above mixes anyway.
ETA wanted to reiterate NEVER been so good!

Mine seem to be doing ok this year. Every week I throw a mix of milk, baking soda and a little detergent and water over them. Have mulched and fed them and they are blooming marvellous and touch wood, no rust, mould or aphids. Roses are a pain in the rrrss but you have to dead head, pull out the old leaves, give them plenty of air circulation and love them dearly and never, ever put the cuttings or dead blooms in the compost.

Another little trick I learnt by ' mistake' years ago. With the roses and aphids - i put bread out for the sparrows and if you put it in the rose bush or under it, they will also feed on the aphids once they have eaten the little bread scraps. Just make sure you are only using safe sprays on the roses if you do this. but it really does work