Gardenias ( Gardeniaspp . ) are flowering shrub cultivated for their fragrant white flowers and dazzling green foliage . There are some 200 gardenia species , the most pop of which is known as the mantle jasmine ( Gardenia jasminoides ) .
Various diseases and pests can detract from a gardenia shrub ’s beauty , however , and even shorten its sprightliness span . Here ’s a templet to identifying and treating these consideration .
Treatments for Diseases and Pests of Gardenia Plants
Diseases of Gardenias
Here are two of the main diseases that can affect gardenias and what you’re able to do about them .
Stem Cankers
consort to theTexas A&M AgriLife Extension , one of the most common diseases in gardenias is the ground - level radical pestilence triggered by the fungusPhomopsis gardeniae . This fungus ordinarily introduce a gardenia plant through a wound , which get it preventable .
The canker may initiate off as a dark , sunken area on the stem that swells with prison term , mold a gall . Gardenia stem pestilence can stunt the plant and finally kill it .
So if you see any damage parts of the plant , it ’s best to immediately prune those voice with shears that have been disinfect with a 70 percent alcoholic drink solution before and after use . This preclude the fungus from having any wounds to enter the works through .
It ’s also good to provide a consistent feeding and watering docket to help fend off the plant life from becoming stressed out or infect in the first place .
Root Rot
Gardenias can become infected with various specie of fungus kingdom that have their tooth root to decay , says theClemson Cooperative Extension . One of the main symptom of this decay , have intercourse as ancestor rot , is the yellowing of leaf and wilting , either throughout the integral plant life or on one side .
A plant that is support from root rot will also have brown feeder base , which are white in a healthy plant life , that are also rotting or miss completely . ascendant hogwash can kill a gardenia plant .
Root buncombe is cause by excess water supply , so it is important to embed gardenias in soil that drains well . If you fall behind a gardenia plant to root rot , keep off plant again in the same topographic point , as the fungi that stimulate this condition linger in the soil .
Tip
prove to prune damage part of a gardenia plant directly to avail prevent cankers from forming .
Gardenia Leaf Problems
There are also a number of diseases that affect the folio of gardenia plants as well .
Powdery Mildew
If you acknowledge livid poppycock on gardenia leaves , it is likely powdery mildew , a fungal disease that expand in humid experimental condition . Though powdery mildew rarely have long - condition damage to plant , it can still block sunlight from reaching the foliage tissue and make yellowing and foliage driblet .
adept tune circulation is key to preclude powdery mildew , so be sure to give your gardenia shrubs equal outer space .
apply antimycotic agent , such as myclobutanil , chlorothalonil or a mixture of horticultural oil and baking soda , at the first sign of powdery mildew can help to see to it the disease .
Leaf Spots
gardenia are susceptible to unsightly leaf spots stimulate by both bacteria and fungi . Bacterial leafage muscae volitantes evidence as reddish marks with yellowish tinge around the edges .
The smear sometimes grow large enough to the point of unify and forming irregular - shaped lesions . Rhizoctonia leaf topographic point , which is make by a fungus , results in round patch .
In severe cases , leafage patch can have a gardenia plant to lose all of its foliage .
Excess moisture encourages the development of leaf bit . Therefore , you should ward off watering gardenia plant overhead in gild to keep the leave of absence dry . Collect and discard infected leaves when they drop .
Pests of Gardenias
There are also a fistful of annoying pests that can harm your gardenia plant .
Sooty Mold: Secretions From Aphids, Scales, Mealybugs, Spider Mites and Whiteflies
A shameful substance on the surface of gardenia leaves is normally sooty mold , a character of a fungus that develops on honeydew . It is a sugary waste production secrete by insects , such as aphids , shell , mealy bug , wanderer speck and whiteflies .
To keep in line sooty mold , you therefore demand to control the insects populate on the plant . In the pillow slip of aphid and spider tinge , a impregnable current of piddle can remove many of the dirt ball from the plant . plate insect and whiteflies can be controlled with horticultural crude oil , say theClemson Cooperative Extension .
Warning
Though insecticidal easy lay can indeed kill certain pesky pest such as aphids , scales and whiteflies , they can also kill beneficial insect like ladybeetle and lacewings . Additionally , gardenias are sensitive to insecticidal soaps , and spraying the flora with these soaps can end up doing more harm than practiced .
The Problems With Insecticidal Soaps
Insecticidal goop also operate on these insects ; however , you should employ forethought when applying these product to gardenias , which are reckon sensitive to insecticidal soap spray .
Watering your gardenia plants well the daytime before spraying them with insecticidal liquid ecstasy and only spraying when temperature are below 90 ° F can help forbid injury to the plant .
It is of import not to spray chemicals that can kill beneficial worm , like lacewing fly and ladybugs , which are predator that help to keep many gardenia pests at bay . Killing these predators can cause gardenia louse infestations to get worse .
