{"id":2669,"date":"2020-01-18T00:03:17","date_gmt":"2020-01-18T08:03:17","guid":{"rendered":"https:\/\/depts.washington.edu\/hortlib\/pal\/pal-question-456\/"},"modified":"2024-04-20T11:46:12","modified_gmt":"2024-04-20T18:46:12","slug":"safety-of-ceramic-pots-for-edible-gardening","status":"publish","type":"pal","link":"https:\/\/depts.washington.edu\/hortlib\/pal\/safety-of-ceramic-pots-for-edible-gardening\/","title":{"rendered":"Safety of ceramic pots for edible gardening"},"content":{"rendered":"

My question is about the ceramic pots that you see in nurseries and
\nplaces in the area. The pots are glazed on the outside, and unglazed on
\nthe inside, and they are made in China and Vietnam. Are these pots safe for planting vegetables and herbs? Or, are there materials in the interiors of the pots that could leach into the soil and make the vegetables and herbs unsafe to eat?<\/strong><\/p>\n

Some ceramic glazes do contain toxic materials, such as lead and cadmium.
\nWashington State Department of Health<\/a> has information on preventing lead poisoning, and on testing for lead.<\/p>\n

State of Oregon’s Lead Poisoning Prevention Program<\/a> includes information on sources of lead exposure, including pottery.<\/p>\n

California Department of Health<\/a> has several pages on toxins in pottery.<\/p>\n

Excerpt:<\/p>\n

“The U.S. Food and Drug Administration (FDA) sets standards at the
\nnational level for the amount of lead that can pass out of, or ‘leach,’
\nfrom dishes. Tableware with lead levels greater than these standards
\ncannot legally be sold in the U.S. The FDA regulations cover only
\ntableware that is imported or that is brought into the state for sale.
\nThe standards apply only to items that are used for foods and beverages.
\nThey do not apply to pieces that either cannot hold liquids or are not
\nintended to hold liquids, such as salt shakers, cookie jars, butter
\ndishes, etc. See the table below for the FDA standards for lead in
\nceramicware.<\/p>\n

Decorative ceramics
\nThe FDA has labeling rules for ornamental or decorative ceramics that are
\nnot intended for food use. These items must either (1) be permanently
\nlabeled with a logo or statement that they are unsuitable for food use,
\nor (2) be made incapable of holding liquid. If an item is clearly
\nintended for food use, such as a bean pot, labeling it is not sufficient,
\nhowever. It must be made unusable, for example, by having a hole drilled
\nthrough any surface that could hold liquid.”<\/p>\n

My co-worker tells me that some retail stores are good about informing customers if pots are unsafe for food use. This
\ndocument<\/a> from Clemson University Extension (although its focus is
\ncookware) suggests that you not use pottery which does not bear the
\nlabel, “Safe for Food Use:”<\/p>\n

If a pot has been fired at a high temperature (something you cannot
\neasily ascertain by looking at it), my thought would be that there would
\nbe less likelihood of toxic material from the glaze leaching inward, but
\nif the clay itself comes from a source which is full of contaminants,
\nthere may be a risk apart from the glaze. If you are at all concerned
\nabout using these pots for growing food, my advice would be not to do it.
\nThere are other ways of growing food in containers, such as untreated
\nwood boxes or barrels. See links here for general information on growing
\nvegetables in containers:<\/p>\n

Vegetable Gardening in Containers<\/a> from Virginia Cooperative Extension.
\nPlants Grown in Containers<\/a> from North Carolina State University.<\/p>\n

Container gardening<\/a>, <\/span>Vegetable gardening<\/a><\/div>\n","protected":false},"excerpt":{"rendered":"

My question is about the ceramic pots that you see in nurseries and places in the area. The pots are glazed on the outside, and unglazed on the inside, and they are made in China and Vietnam. Are these pots safe for planting vegetables and herbs? Or, are there materials in the interiors of the pots that could leach into the soil and make the vegetables and herbs unsafe to eat? Some ceramic glazes do contain toxic materials, such as…<\/p>\n

Continue reading Safety of ceramic pots for edible gardening<\/span><\/a><\/div>\n","protected":false},"author":4,"featured_media":0,"menu_order":0,"template":"","keyword":[247,52],"class_list":["post-2669","pal","type-pal","status-publish","hentry","keyword-container-gardening","keyword-vegetable-gardening"],"acf":[],"_links":{"self":[{"href":"https:\/\/depts.washington.edu\/hortlib\/wp-json\/wp\/v2\/pal\/2669"}],"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=2669"}],"wp:term":[{"taxonomy":"keyword","embeddable":true,"href":"https:\/\/depts.washington.edu\/hortlib\/wp-json\/wp\/v2\/keyword?post=2669"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}