As a backyard vegetable garden staple , a tomato plant life ( _ Lycopersicon esculentum _ ) naturally has green leaves and stems . So if you mark * * white spots * * on your plant life ’s leaves , you ’ll cognise something is amiss . reckon intimately to determine if the spot are a symptom ofdiseaseor if they may be telltale sign ofinsects — their skin or excreta .
Tip
Although it ’s atender perennialin U.S. Department of Agriculture plant hardiness zones 10 through 11 , the tomato is grown as anannualin other areas .
Diseases
Several fungal diseases may cause tomato leaves to have lily-white spots . These spots are fungal spores , one level of the disease .
Powdery Mildew
Typically mutual when the humidity is high , powdery mildewinitially causeswhite spotson tomato leaves that typically spread across a folio ’s surface . Most fungicides are applied only as protective measures — before the disease takes hold — or they ’re generally ineffective in hold in the disease . But one biological controller may be successful in see powdery mildew after it appears . Look for the active ingredientBacillus subtilis , a bacterium approve for organic horticulture . Typically , you ’ll mix 2 to 4 ounces in 1 congius of water and spray all surface of a tomato flora thoroughly until the product endure off . You may need to repeat this program every seven days to keep the disease under control .
enforce this bacteria as a fungicide works well when you get down treating plant at thefirst signsof powdery mould .
Warning
Even thoughBacillus subtilisis approved for organic gardening , exercise caution when using it . bust a long - sleeved shirt , long pants , sock , shoes and waterproof gloves . Do n’t use the product in windy conditions because it ’s harmful if inhaled .
Septoria Leaf Spot
Septoria leaf spotis another fungal disease that causes white-hot spots on tomato leaves . you’re able to tell the difference between this disease and powdery mildew becauseseptoria leafage spotstypically have brown borders and powdery mildew bit are solid white . utilize a product withchlorothalonilas the basal element , typically at the rate of 2 teaspoon per 1 gallon of water , and coat all plant surfaces thoroughly . Reapply every seven to 10 24-hour interval . Wash your hand after using and keep the product out of compass of baby or pets .
Do n’t plant tomatoes in the same billet where last year ’s plants were infect with this disease . The fungus can overwinter in the land and infect the following year ’s plants .
Insects
Aphids
Aphidsare insects that prey on the cell fool in Lycopersicon esculentum leaves . Although the insect are not white , they shake off their skins as they grow . Theseskin castingsare snowy and are typically leave on folio surfaces , like a sprinkling of white smear . ascendency aphids without using chemical substance by spraying them with ajet of waterfrom a garden hosepipe , which knocks them off plant life .
Psyllids
Psyllids are insects that also feed on tomato folio cell sap . They egest white waste material , which look likegrains of sugaron the leaves . detritus leave withsulfur , particularly the undersides of leaves , to curb psyllids .
Using a horticultural oil after applying S to tomatoes can harm the flora . When applying S , do not rest the Cartesian product or apply on a wordy mean solar day and lave your hands after using . Store out of the grasp of shaver or favourite .
