Geraniums are , in my opinion , some of the happiest plants in the garden .
Those mounds of green leaf are smothered by bright , pollyannaish blossoms all summertime long , and it ’s enough to plagiarize anyone ’s spirits .
But the plants themselves seem to be pretty happy , too , judging by the fact that they so rarely seem to have problems .
Photo by Penn State Department of Plant Pathology & Environmental Microbiology Archives, Penn State University, Bugwood.org.
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Do n’t let it get you ( or your plant ) down if diseases do come chit-chat , though . It happens to all of us – no matter how persevering we are – at some point .
come up , we ’re plump to expect at nine unlike diseases that can do problems with geranium . Many are well address , but a few can spell disaster if they take hold .
Either way , we aim to help oneself you describe the issue and address it as best as potential . Here are the disease to watch for :
9 Common Geranium Diseases
If you ’re noticing yellow leaves , slur , or some funny - looking fuzz , you ’re plausibly eager to figure out what the heck is causing it , so allow ’s not dally .
1. Alternaria Leaf Spot
If you examine the lower surface of the leafage and detect raised quarter- to half - inch water - hit it up speckle , it ’s prison term to surmise Alternaria leafage blot .
triggered by the fungusAlternaria alternata , it normally start up on the scummy leaves before move up to the eminent ones . When the humidity is gamy , these spots will develop a blurred chocolate-brown grain .
This disease can be spread out by water or on tools , so be sure to water at the soil grade rather than sprinkle the leaves , and clean your tool good with Georgia home boy and water between plants .
Once the disease has developed , the respectable result is to spray the plant every few week with a copper - based antifungal .
Bonide Liquid Copper Fungicide
I like Bonide ’s Liquid Copper fungicide – you cangrab some at Arbico Organicsin 32 - Panthera uncia quick - to - economic consumption , 16- or 32 - ounce hosepipe conclusion , or 16 - ounce concentrate container . But any sometime liquid copper fungicide will do .
Just come the manufacturer ’s directions for app and employ every two week as long as symptom are present .
2. Bacterial Blight
Bacterial blight is bad news . It causes diminished sunken spot on the undersurface of the leaves , and the folio may finally wilt while the stem stays house .
Symptoms normally first appear on the lower leaf , and these leaves will turn grayish - brownish and become flat off .
This disease is make by the bacteriaXanthomonas campestrispv.pelargonii . Once the industrial plant is impacted , there is no cure .
To avoid it , wash your garden peter , H2O at the soil level , and leverage plant that appear respectable and show no signs of disease . This will avail to prevent introducing the bacterium into your garden or spreading it if it ’s present .
Fortunately , this pathogen only flack geraniums so you do n’t ask to worry about it spread to or from other type of plant life in the garden .
3. Blackleg
Water molds in thePythiumgenus campaign a disease commonly have sex as blackleg . It impact a wide range of plants , admit our endearing geranium . You usually see it in circularize cutting but it can happen at any point , and it can spell cataclysm pretty cursorily .
At first , the base of the seedling stem turns brown and appears fuddled . Then , the buncombe turns black and extend up the stem three or four column inch . At that point , your geranium is toast .
On older plants , the bunkum may start underground in the roots , but the solution is the same .
Overwatering can exasperate the problem , and it can bespread by fungus gnat .
If you catch it early , before the stem is entirely deaden , you may block up scab in its tracks . Mycostop biofungicide is extremely effective . It contains the beneficial bacteriaStreptomycesStrain K61 .
Mycostop Biofungicide
4. Botrytis Blight
Botrytis blight , due to the fungusBotrytis cinerea , impacts the flowers first – which is both good and risky news .
It ’s good because this means you could unremarkably spot it and begin cover your plant quickly . The flowers are the main grounds we keep geraniums in our garden after all , right ? We run to look at them a flock more than we do the leaf !
The uncollectible news is that it break your pretty display until you’re able to settle the problem .
The bloom on your geraniums will reverse browned and flow from the plant . The challenge is figuring out if the bloom are infected or if they are just spend .
An easy way to tell is to count at any place where a petal has put down on a folio . You ’ll see a white-livered or brown spot sort , with temporary margins . If that symptom is present , you could be sure botrytis has paid your garden a visit .
The fungus that causes this disease is just waiting for you to make some sort of yap in the plant so it can purloin in .
That means it ’s authoritative to try not to damage your geranium at all , whether that is from accidentally hitting it with the edger , via hail hurt , or if your dog ( theoretically ) steps on one . Not that that has ever happened to me , of course .
That also means you really , really want to avoid pest trouble . Every metre anaphidorcabbage loopertakes a bite out of a leafage , that ’s leave the works exposed .
You should also snip off off any discredited or dying leave and any spent flower straits right out . Good spacing and airwave circulation also help to prevent Botrytis blight .
If your plants fall ill despite your best efforts , antifungal agent can eliminate the fungus . You just need to be sure that yourotate the chemical substance you use . Apply something like a copper fungicide for a few workweek followed by neem fossil oil for a few weeks , for example .
There is even a biofungicide available made using the beneficial fungusUnocladium oudemansii(U3 strain ) that is exceedingly effective for putting an end to this infection .
BotryStop Biofungicide
If you decide to go this route , you could purchase a six- or 12 - pound bagof BotryStop at Arbico Organics .
It ’s overnice to have on script because it can kill a number of dissimilar fungous pathogen . Just do n’t forget to rotate in a fuzz fungicide or something else every few weeks until symptoms subside .
5. Fasciation
Fasciation ( am I the only one whose brain desire to convert that Word of God to “ fascination ? ” ) is because of a bacterial pathogen known asRhodococcus fascians .
It cause leafy galls , which is also another name for the disease . This is the ontogeny of short , stumpy , bunched - up foliage which forms at the base of what otherwise looks like a normal geranium plant .
If you blemish this problem , you do n’t need to remove your plant life from the garden . But do n’t use them to propagate new geraniums , and don’toverwinter the plantsfor growing next year .
You do n’t want to pass the disease on to next geranium plants , but it wo n’t spread to other metal money in your garden .
6. Pseudomonas Leaf Spot
genus Pseudomonas leaf spot can mimic many other diseases because it demonstrate in minuscule , fourth - inch maverick post with a dark essence .
The spots may have a yellow halo around them , but do n’t rely on this as a marker because it may or may not be present . The spots can finally unite together and kill off the leafage .
The bacteria that do the disease , Pseudomonas cichorii , infects many different species . And it can spread rapidly through a garden via water .
pelting or irrigation splashing , or even water droplet in the air from humidness , can spread this pathogen .
That ’s why good spacing and watering at the soil level rather than from smash on the foliage is so of import . You should also water in the sunup so the leaves can dry chop-chop in the afternoon Dominicus and heat .
It can also be spread by insects , which is why you need to do your best to keep your garden pestilence - complimentary .
Once the disease charter hold , trim away any infected leaves and treat your geranium with a copper fungicide .
7. Root Rot
beginning rot can be due to two thing . The first is simply watering too much . This impoverish the roots of oxygen and they die off . The 2d is fungi in thePythiumgenus ( see rat above ) .
Both cause the antecedent of the geranium to turn dour brown or black and soupy . Once the roots die off , the upper share of the plant apace play along .
It can be hard to separate what ’s going on because the genuine action is all happening underground . Above soil , you might see wilting , stunting , or no young growth , and flowers that just generally look sorry .
The only way to order what ’s going on is to dig up your geranium and count at the roots .
It ’s moderately hard to separate whether the cause is overwatering or a fungus , so it ’s best to just handle for both . Reduce watering and ensure you are n’t adding water until the soil has dry out out an inch deep .
Then , use Mycostop as described above for regale rat .
Find more tips for preclude and regale root rot here .
8. Rust
Rust was well - name because it look just like it sounds like it would . On the top of the leaf , you ’ll see white-livered spots , but if you rear the leaf up and look underneath , you could see rust fungus - colored spores .
Rust is a rough-cut disease that impacts many dissimilar plant , but the fungus that specifically attacks geraniums isPuccinia pelargonii - zonalis .
think how we mention that copper fungicide is your friend ? Once again , it make out in handy here . expend it every few workweek for as long as symptoms are present , and then keep using it for a few weeks more .
9. Verticillium Wilt
If you imagined that a disease with “ wilting ” in the name would lead in wilt folio , you ’d be veracious .
Verticillium wilt disease can bet a fortune like bacterial blight because the industrial plant simply turns brown and collapses . However , you wo n’t see the spot that can sometimes be present with blight .
or else of being because of bacteria , this disease is because of a fungus – eitherVerticillium albo - atrumorV. dahliae .
Usually , by the sentence you see symptom , the disease is well advanced . attend for triangular yellow wedges forming at the base of the leave , followed by defoliation and collapse .
There ’s no in effect mode to treat it , so avoid Verticillium wilting in the first place by assay out insubordinate cultivars ( they ’re mutual ! ) , rotating where you plant geraniums every two or three years , and solarizing the grunge between planting .
Say “Hello” to Big, Healthy Geraniums
Do n’t allow this listing get off you into a scare . While there are many different diseases thatcanimpact geranium , that does n’t mean your plants are under constant threat from all sides .
If you do start to see weird growths , funny spot , or yellow leaves , we hope this template helped set you on the proper path .
If you ’re eager tocontinue your geranium growing dangerous undertaking , we ’d love to aid out . And we have a handful of other helpful guide you might find interesting . see to it these out next :
© inquire the Experts , LLC . ALL RIGHTS RESERVED.See our TOSfor more detail . intersection photos via Arbico Organics . Uncredited photos : Shutterstock .
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Kristine Lofgren
