Roses are one of the most beautiful and enticing gifts in nature, but like any other good thing, there's always something to spoil it. In horticultural information, we know that most varieties of roses are susceptible to fungi, pests, and diseases, except for the culled rose, which is bred to resist diseases and pests. With a little effort and persistence, you can have beautiful roses that are free of bugs, fungi and diseases.The following content also has some reference value for raised garden beds.
Just as the name sounds, black spot covers the leaves of your rose with smaller and larger black spots. Fungi live in debris that accumulates under roses, so keep the garden clean and free of debris. Humidity and humid conditions also seem to be a factor, so try to water only the ground and not the rose leaves.
Treat Dark spots: Clean up all debris scattered on the rose bed. Remove all infected leaves and place them in a closed container (not in the yard or compost). If dark spots persist, a fungicide, such as sulfur powder, can be used. After pruning the roses, be sure to sterilize them with rubbing alcohol.
Like black spot, powdery mildew is caused by a fungus that lives in the debris piles beneath roses. Powdery mildew looks like someone walking by and sprinkling baby powder on your roses - except it doesn't do much good!
The treatment for powdery mildew is basically the same as for other rose fungal infections: Clean up all the debris that has littered the rose beds. Remove all infected leaves and place them in a closed container. If the problem persists, a fungicide such as powdered sulfur can be used. A homemade remedy is to spray a mixture of a teaspoon of baking soda, half a teaspoon of canola oil, and a quart of warm water.
Another fungus that roses are susceptible to is Phragmidium, which causes a strange orange-red discoloration on rose leaves that looks like rust. Rose rust usually starts at the bottom and spreads to the top.
You can clean up all the debris scattered on the rose bed. Then remove all infected leaves and place them in a closed container. If rust is still present, you can also use a bactericide, such as sulfur powder or homemade baking soda spray.
Did you know that maggots grow up to become Japanese beetles? Grubs live underground and feed on grass roots, which can lead to large areas of dead grass.
The Japanese beetle is characterized by its shiny copper-green shell and poor flight ability. They like to nibble roses in groups, drilling huge holes in the leaves before nibbling on the next one.
Your first line of defense is to shake them off the roses and drop them into a bucket of soapy water.
For harmful invasions, spray organic insecticides as needed.
To kill them in their larval stage, use a milky white sporangium powder on your lawn.
Aphids are small green bugs that slowly nibble through small holes in rose leaves. Although it's hard to see, you'll notice some small holes that seem to get bigger over the course of a week or so.
Aphids are abundant, but because of their light green color, they mix easily. The first step to stopping the aphid invasion is to remove the leaves where the aphid have gathered and then throw them into a closed container.
If the aphids have spread beyond a few leaves, your best bet is to spray a mixture of water, liquid dish soap, and canola oil. The solution is not harmful to plants, but it makes it difficult for aphids to breathe.
Another innovative aphid treatment is ladybug! While we may think of ladybugs as harmless little bugs, they are actually the number one predator of aphids.