Difference between revisions of "Deal with Black Spot Leaf Disease"

#Prune infected leaves immediately.<ref name="rf1">http://www.gardeners.com/how-to/common-flower-diseases/8109.html</ref> Ensure the overall health of your plant by removing diseased leaves entirely. To prevent the spread of disease through contact with the plant or soil, throw them away immediately with your regular trash before doing any more work in the area. Further prevent the disease from spreading by disinfecting your tool immediately after pruning each leaf. Have a solution of 1-part bleach to 4-parts water within easy reach.<ref name="rf2">http://www.planetnatural.com/pest-problem-solver/plant-disease/bacterial-leaf-spot/</ref>.

#Treat infected areas. If cutting every infected leaf from your plant or tree means cutting most if not all of its leaves, prune the ones that have already turned entirely yellow or are about to, since these are most likely too far gone to recover. Treat all remaining leaves, including their bottoms as well as their tops.<ref name="rf3">http://www.agardenforthehouse.com/2012/05/got-black-spot-get-milk/</ref> Although there is no guaranteed cure for black spot disease,<ref name="rf2" /> try the following remedies, which can slow and prevent the disease from spreading, and use whichever shows the best results:

#*Mix together a solution of 1 tbsp. baking soda, 2.5 tbsp. vegetable oil, 1 tsp. liquid soap, and 1 gallon water. Be sure to use liquid soap, not detergent. Since this may potentially burn your leaves, spray a small test area with the solution before spraying the entire plant. If burning is absent or minimal, spray the leaves once every two weeks.<ref name="rf2" />

#*Combine 1-part dairy milk to 2-parts water. Spray the leaves once each week. (Sorry, vegans; non-dairy milk substitutes won’t work).<ref name="rf3" />

#*Spray the leaves with neem oil once every two weeks.<ref name="rf2" />

#*Use fungicides as a last resort if the disease returns for multiple growing seasons.<ref name="rf4">http://www.extension.umn.edu/garden/yard-garden/trees-shrubs/management-of-leaf-spot-diseases/</ref> Follow their directions regarding applications. Apply them early, before outbreaks or at the first sign of spots, since they are preventative in nature. Choose organic products if possible for both the plant’s health as well as pollinating insects.<ref name="rf2" />

#Rake continually. Keep the base of the plant or tree clear of infected leaves that may have fallen on their own. Clear away all fallen leaves, whether they’re infected or not, since beds of dead leaves trap and retain moisture, thus creating a ripe breeding ground for the disease. Be sure to rake straight up to winter’s first snow, or even after if needed; the disease may survive the cold weather and reinfect the plant or tree when spring comes.<ref name="rf4" />

#Prune the upper canopy. Check the lower leaves regularly to see how much sunlight they receive. Make sure they’re not constantly shaded by the upper reaches of the same plant or tree or any neighboring ones. If they are, trim leaves and branches from the top to allow sunlight to penetrate to the bottom and dry the lower leaves more efficiently.<ref name="rf4" />

#Water your plant or tree properly. Water the soil directly. Keep the leaves dry.<ref name="rf1" /> Avoid overwatering. Allow soil to dry before watering again.<ref name="rf4" /> Refrain from watering during rainy weather.

#Keep the air circulating. Weed the soil to improve airflow.<ref name="rf1" /> Apply a level amount of mulch around the base of the plant or tree, leaving a ring of free space between the mulch and the trunk. Prevent weeds from growing while improving the area’s ability to dry more thoroughly.<ref name="rf4" />

#Purchase resistant varieties of plants. Research the type of tree or plant that you wish to include in your landscape. Find out if any particular variety has been proven to be resistant to the disease.<ref name="rf1" /> If the cost of resistant varieties is significantly higher than non-resistant ones, ask yourself which you value more: saving money now or time and labor later.

#Space new plants well apart from each other. Whenever you plant new saplings or young plants, picture the size they’ll reach once fully grown. Plant them accordingly, allowing each plenty of distance from the rest in the future.<ref name="rf4" /> Preempt the easy spread of disease by keeping one plant from touching another once they’ve matured. Allow sunlight to reach and dry the lower leaves throughout their lifetime by eliminating the excessive shade that overcrowded canopies would otherwise provide.

#Avoid planting in overly moist areas. Since moisture facilitates black spot disease, plant in areas that dry easily after rain. Choose spots that receive direct sunlight for at least a portion of the day.<ref name="rf1" /> Keep clear of areas that are prone to standing water.

#*Also adjust any lawn sprinklers so they don’t soak your leaves unnecessarily.<ref name="rf4" />

 

 

*For tall infected trees, hire a professional or invest in a high-pressured sprayer in order to apply fungicides or other treatments to the highest leaves.<ref name="rf4" />

*Do not apply treatments when pollinating insects are around.<ref name="rf2" />