"Natural Girl" wrote:

How long do you think it should it be
composted before it's safe to use it?

All manure needs to be composted a minimum of one year before used in
a garden. When too fresh it will damage plant roots so by the time it
composts in the ground and your plant roots heal enough that they
would be able to use its nutrients most will have washed away from
rain/watering. The best way to use manure is to have it well
composted, turn it into a weak tea, and then apply judiciously about
once every ten days. Applying fresh manure directly to soil does more
harm than good.