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Using composted manure in the vegetable garden
A lot of livestock owners toss all the bedding and manure into a compost pile when they muck out the pens, and eventually add it to the garden.
Soil Scientist Craig Cogger at Washington State University says not all manure carries bacteria such as E-coli and salmonella, but there's no way to tell without extensive lab testing. In a properly-managed compost pile, pathogens begin dying off when temperatures inside the pile reach at least 131-degrees for three-days.
"And then you turn the pile, and you allow temperatures to reach that point again for another three days, and you repeat the process five-times. For the small-scale composter who's not likely to meet those temperatures, my feeling is we should probably wait a year," says Cogger. "The pathogens are going to die over time, even if we don't have those temperatures."
If the manure has only been composting for a few months, Cogger says you can use it on low-risk vegetables that don't touch the soil, and those you know you're going to cook.
"Sweet corn, use your compost there. You're growing winter squash, use it there, even something like broccoli which is up off the ground. If you're growing lettuce, radishes, carrots, spinach, things you're going to eat fresh, things that are in the ground, or touching the ground, it's very hard to wash all of the soil off of them, don't grow them where you're putting your manure this year, but next year you can rotate them in," he says. "Now a full year has passed."
Composted manure improves the soil and water-holding capacity. However, with the exception of chicken manure, Cogger says it's not a rich source of nutrients so you may need to add some fertilizer.