Blights admit a range of plant disease that share one coarse symptom : a slow death . plague first reason leaves or branches to chop-chop wilt and stop originate , and later other plant section may or may not moulder . blight that affect cucurbit vegetables , such as cucumbers ( Cucumis sativus ) , often cause rotting of the vines and fruits . Because blight dissemble so many dissimilar plants , you have to constrict down the potential disorders by identify the symptoms and matching them with the blight that normally affect cuke , which admit gummy stem ( Didymella bryoniae ) , phoma ( Phoma cucubitacearum ) , early or alternaria ( Alternaria cucumerina ) and phytophthora ( Phytophthora capsici ) .
Identification
Step 1
Check the cuke leave for brown , on an irregular basis shaped round spot , and check the fruit for soppy , sunken depressions of varying size that ooze a black , gummy liquid state , to determine if your flora have gummy stem blight or phoba blight .
Step 2
Examine the cucumbers for a lean level of white , cottony mould that covers the peel and eventually overtakes the yield , a potent indication of genus Phytophthora blight . The vine of cucumber plant life infected with genus Phytophthora blight moulder at or just above the soil line .
Step 3
reckon at the leaves for modest brown spots with yellowed rings around them that farm to exclusively brownish spots about 3/4 inch widely , a sign ofalternaria leaf blight . Other sign of alternaria foliage blight include brown , upward - curling leaves , and chocolate-brown halo with several concentrical yellow circles . Alternaria foliage blight often starts with the mature leaf around the plant ’s crown .
Cultural
mould the expanse you will plant the cucumbers in to a deepness of 12 in as soon as the temperature stays above 70 point Fahrenheit during the day in spring . Remove and rock or dust from the sphere .
Water the soil 12 inches deep using a sprinkler or a soaker hosiery . Cover the planting arena with a art object of 2 - mil percipient plastic sheeting and tuck the edges into the soil to secure it . Place rocks around the edge if you live in a airy area .
will the plastic on the grime for eight to 10 weeks if the temperature stays between 70 and 80 degrees Fahrenheit , or for six to eight calendar week if the temperature stays between 80 and 95 F. Sterilizing the soil kills the soil - borne fungus that causes pasty radical blight and phoma blight .
Step 4
irrigate the cucumbers using a pelter hosepipe or other drip - irrigation organization to minimize the condition that favour blight diseases .
Step 5
Prune and care for the cucumber vine flora when dry . work with sloshed plants can diffuse blight fungus around to other plants and into the soil .
Step 6
take plant touch on by alternia leaf blight at the goal of the time of year and give them to your sanitation service on garden wasteland pickup twenty-four hours .
Step 7
Grow another plant life other than a curcurbit every two or three years in the soil normally used to grow cucumbers . Rotating out the cucumbers for anything other than a curcurbit for one year pass the fungus that causes alternaria folio blight , as it survives in cucurbit plant rubble .
Chemical
Mix together 3/4 teaspoon of a fungicide containing 29.6 percentage chlorothalonil with 1/2 gallon of water system for every 100 square feet of growing area in the cooler of a pump - case nebulizer if the cucumber vine have gummy stem blight or alternaria leaf blight . Spray the cucumber vine and foliage as shortly as the first true leaves emerge or at the start of the rainy season , whichever comes first . reprise every seven to 10 solar day throughout the growing time of year .
Mix together 1 tablespoon of 7 percent liquid copper concentrate with 1 gal of water supply in a ticker - eccentric sprayer at the first augury of phoma blight or alternaria leaf blight . Spray the all parts of the cucumber plants until cover on all sides , and repeat every seven to 10 solar day , as involve . you’re able to also spray copper on the cucumber as a preventative step when the rainy time of year starts .
Mix together 1 tablespoon of 50 per centum captan with 1 gallon of water in the cooler of a pump - eccentric sprayer if the works have phytophthora blight . Spray the foliage until cover on both side , and repeat every 10 to 14 days as needed .
Tip
Buy seeds from companies that address their cucumber germ with fungicides or produce their come in arid realm , such as California ’s inland valley , to help foreclose gummy radical blight and phoba blight .
Spray pesticides on a calm daylight to derogate drift .
Warning
Always wear chemical - proof boxing glove , a respirator and condom goggles when mix and apply garden chemicals .
If you ’re pregnant or nursing , fag heavy - duty garden gloves when crop with soil to prevent skin link with soil - tolerate pathogens .
Keep garden chemicals out of reach of children .
Do n’t allow children or pets in an area cover with fungicides until they dry .
Do n’t compost plant affected by blight , but give them to your sanitization armed service on garden waste pickup day .
Stop using fungicides 30 days before harvest .
