Your easy - to - maintainannual petuniasthat offer color and sake to your garden are under the threat of fungus problems that may snipe and have disease . Maintain vigorous petunias because healthy plant have a much bully capacitance for avoiding and recuperate from disease than counteract plants . Petunias ask full sunlight for optimum emergence as well as light , well - drained soil with a pH of 6.0 to 7.0 .

Verticillium Wilt

Verticillium wilt is a fungous disease that attacks petunias among approximately 300 other host plants . triggered by the pathogen Verticillium albo - atrum and Verticilliumdahliae , this fungus problem can be extremely damaging to your family garden petunias . A soil - borne disease , symptoms admit stain on bow as well as areas of die plant tissue . wilt , yellowing and foliage death is also common . As works death can come , do not replant with another petunia . Soil - borne pathogens proceed to inhabit the soil after the plant dies . Though fungicides apply right away to your petunias are not advocate as a ascendence measure , certify professionals may be able-bodied to assist with a fumigation process . For domicile management , hit and destroy touched plant life parts or intact works in severe cases . wield vigorous Petunia and keep weeds under dominance with hand remotion or the software of herbicides because weeds attract pathogens and often act as initial innkeeper plants .

Powdery Mildew

Powdery mould fungi tone-beginning petunias with a display of soft - to - recognize symptom . When fungus fire , powder - like spot of a mould - like substance variant on plant control surface in addition to the formation of white fruiting body , or maturation , that become black . Symptoms occur on leaves , stems and flowers . Appearing most prevalently in siccative climates and tender temperatures as well as in moist , shaded conditions , powdery mildew is controllable through cultural direction by avoiding overhead irrigation and removing and put down stirred plant life parts to forestall further spread of the fungus . For chemical control , use a sulfur - based fungicide or a antifungal agent with the active component triforine . engage the enjoyment of a botanic fungicide like neem oil for lower toxicity . Make practical program once every one to two weeks during the growing season , according to the Colorado State University Extension .

Phytophthora Root and Crown Rot

Phytophthora etymon and treetop rot of petunias is triggered by the fungus Phytophthora parasitica . This soil - bear pathogen retain to live within soil without a definite life anticipation . The exercise of immune flora like snapdragons and marigolds is ideal because they are much less likely to become infected . If you are remove a genus Petunia works that has died from root rot , replace it with a tolerant alternative instead of with another genus Petunia . symptom include decay near the grime agate line let in the crown , or base , of the petunia plant as well as the roots . Visible symptom are heavy to come by but discoloration and die plant tissue paper may occur . to boot , your petunias may finish get and farm flowers or the integral industrial plant will die . For ascendancy , adjoin a commissioned master to specify up a preventive fungicidal soil drench programme . keep extremely well - drained dirt and apply a fungicide with the fighting ingredient metalaxyl . Only apply a fungicide if you are providing the optimum sustainment to your petunia plant , harmonise to the Utah State University Cooperative Extension .

References

…