Tips on dealing with the most common rose health problems

Black Spots On Leaves

This disease is commonly known as black spot. Black spots appear as circular with fringed edges on the leaves, and they cause them to yellow. The solution is to remove the infected foliage and pick up any fallen leaves around the rose. Artificial sprays can be used to prevent or treat this kind of rose disease.

Stunted Or Malformed Young Canes

Known as powdery mildew, this is a fungal disease that covers leaves stems and buds with wind spread white powder. It makes the leaves curl and turn purple. Spray with Funginex or Benomyl to treat this particular disease which could totally ruin your rose garden.

Blistered Underside Of Leaves

A disease of roses known as rust, it is characterized with orange-red blisters that turn black in fall. In spring it will attack the new sprouts, and this disease can even survive the winter. What you should do is to collect and discard leaves that are infected in fall, and also spraying Benomyl and Funginex every 7-10 days will help.

Malformed Or Stunted Leaves And Flowers

The one most likely cause of this is the presence of spider mites. These are tiny yellow red or green spiders which cling to the underside of the leaves. They will suck the juices from the leaves, but the application of Orthene or Isotox may help in treating this infestation.
Weak And Mottled Leaves Showing Tiny White Webs Underneath

This might be caused by aphids, which are small soft-bodied insects which are usually brown green or red. Often found clustered under leaves and flower buds, they suck plant juices from tender buds. However Malathion or Diazinon spray may help roses to survive these bugs.

Flowers That Do Not Open Or Are Deformed When They Do Open

Thrips could be the reason behind this deformation and unopened flowers, which is characterized with slender brown-yellow bugs with fringed wings thriving in the flower buds. They will also suck the juices from the flower buds, so therefore you should cut and discard all infested flowers. Using Orthene and Malathion will also treat this health problem with your roses.