Q: I live Atlanta and would like to know where can I obtain free compost in the city. Have you, or others you know, tried manures from the Atlanta Zoo? While on the subject, how long does it take for manure to be usable in the garden?

A: Megan Klein-Winokur, public relations manager at Zoo Atlanta, says that it is zoo policy not to make animal manure available to the public. There are so many kinds of animals at the zoo that it would be a monumental task to keep the manure of “safe” animals like the elephants away from the manure of meat-eaters.

The City of Atlanta Yard Trimmings Diversion office does sponsor a once-a-year free compost pick-up weekend. This year it will be March 31 and April 1. The site is 625 North Avenue, across from City Hall East. Residents can obtain as much as one cubic yard of compost.

If you prefer to use fresh, rather than bagged, manure you’ll have to do a bit of detective work. Some farms advertise their manure in the Farmers and Consumers Market Bulletin (free, 404-656-3722). You might also call the non-profit Georgia Organics group (770-621-GOGA) and ask if their organic gardening members have reliable sources. Ask your friends if they know someone who owns or rides horses; maybe they can provide leads.

Manure is a wonderful soil amendment but it does have a few problems. Weed seeds in the manure are much more of a problem than its odor. Fresh manure from horse farms has thousands of weed seeds in it. Try always to specify that you want manure that has weathered outdoors for several months so weed seeds will be minimized.