{"id":2746,"date":"2019-05-18T00:04:34","date_gmt":"2019-05-18T07:04:34","guid":{"rendered":"https:\/\/depts.washington.edu\/hortlib\/pal\/pal-question-540\/"},"modified":"2024-12-03T13:57:34","modified_gmt":"2024-12-03T21:57:34","slug":"treating-powdery-mildew-on-nandina","status":"publish","type":"pal","link":"https:\/\/depts.washington.edu\/hortlib\/pal\/treating-powdery-mildew-on-nandina\/","title":{"rendered":"treating powdery mildew on Nandina"},"content":{"rendered":"

Can you give me some suggestions on how to treat a Nandina infected with powdery mildew?<\/strong><\/p>\n

 <\/p>\n

Apparently, powdery mildew on Nandina<\/em> is becoming a common problem in our
\narea, as the article linked here<\/a> indicates.<\/p>\n

While this fungal disease is unsightly, it generally does not kill
\naffected plants. Sometimes improving air circulation around the plant (by
\npruning congested growth) can help, and making sure to practice good
\nsanitation by picking up fallen leaves affected by the mildew is also
\nimportant.<\/p>\n

There is an interesting idea in this Science News<\/a> article on
\nusing milk powder in water as a spray to control the disease.<\/p>\n

Several organic gardening sources recommend a baking soda spray. The
\nOrganic Gardener’s Handbook of Natural Insect and Disease Control<\/em> by
\nBarbara Ellis (Rodale Press, 1996) recommends dissolving 1 teaspoon of
\nbaking soda in 1 quart of warm water. You can add up to a teaspoon of
\ndish soap to make the solution stick to the leaves more effectively.
\nHere<\/a> is another source with slightly different recommendations, from the
\nNational Sustainable Agriculture Information Service.<\/p>\n

More from University of California, Davis.<\/a> Excerpt:<\/p>\n

\n

Shade and moderate temperatures favor most powdery mildews. Locate plants
\nin sunny areas as much as possible, provide good air circulation, and
\navoid excess fertilizer. A good alternative is to use slow-release
\nfertilizer. Overhead sprinkling may actually reduce the spread of powdery
\nmildew because it washes spores off the plant; also, if spores land in
\nwater, they die. The best time to irrigate is in mid-morning so that the
\nplants dry rapidly, reducing the likelihood of infections by other fungi,
\nsuch as the ones that cause rust or black spot infections on roses. As
\nnew shoots begin to develop on perennial plants, watch closely for the
\nappearance of powdery mildew.<\/p>\n<\/blockquote>\n","protected":false},"excerpt":{"rendered":"

Can you give me some suggestions on how to treat a Nandina infected with powdery mildew?   Apparently, powdery mildew on Nandina is becoming a common problem in our area, as the article linked here indicates. While this fungal disease is unsightly, it generally does not kill affected plants. Sometimes improving air circulation around the plant (by pruning congested growth) can help, and making sure to practice good sanitation by picking up fallen leaves affected by the mildew is also…<\/p>\n

Continue reading treating powdery mildew on Nandina<\/span><\/a><\/div>\n","protected":false},"author":4,"featured_media":0,"menu_order":0,"template":"","keyword":[569,166],"class_list":["post-2746","pal","type-pal","status-publish","hentry","keyword-nandina-domestica","keyword-powdery-mildew-diseases"],"acf":[],"_links":{"self":[{"href":"https:\/\/depts.washington.edu\/hortlib\/wp-json\/wp\/v2\/pal\/2746"}],"collection":[{"href":"https:\/\/depts.washington.edu\/hortlib\/wp-json\/wp\/v2\/pal"}],"about":[{"href":"https:\/\/depts.washington.edu\/hortlib\/wp-json\/wp\/v2\/types\/pal"}],"author":[{"embeddable":true,"href":"https:\/\/depts.washington.edu\/hortlib\/wp-json\/wp\/v2\/users\/4"}],"wp:attachment":[{"href":"https:\/\/depts.washington.edu\/hortlib\/wp-json\/wp\/v2\/media?parent=2746"}],"wp:term":[{"taxonomy":"keyword","embeddable":true,"href":"https:\/\/depts.washington.edu\/hortlib\/wp-json\/wp\/v2\/keyword?post=2746"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}