When is the best time to add cow manure to my vegatable garden?

When it is composted. The urea mixed in the manure can burn plants.

http://homeguides.sfgate.com/apply-cow-manure-beds-43287.html

http://www.brighthub.com/environment/green-living/articles/100141.aspx

https://www.bettervegetablegardening.com/cow-manure-fertilizer.html

https://www.bing.com/videos/search?q=best+time+to+add+cow+manure+to+my+vegetable+garden&qpvt=+best+time+to+add+cow+manure+to+my+vegatable+garden&FORM=VDRE

I've always added manure to my garden in the fall so it would have all winter and spring to "melt in" and then I till it all up before planting. But I don't see why you couldn't just add it in the spring too.

Add it prior to planting while preparing the soil for planting.

I would normally do it in the fall or winter to give it time to decompose and before you till the bed and plant. However, it can be done at other times, but kept away from plant contact.

Okay, this is too funny, again, I agree with you Ken! I too add my manure, compost in the fall, the rain and snow help it decompose and get way down there where the roots will be growing and needing nutrients in the spring. I have also been known to add some "boost" in the spring around some specific plants that need without any problems, but from experience, I believe the fall is better in the long run.

jojo ;-)

The best time is in the fall, but if it fully rotted with no smell, it will be okay to use now but must be dug in thoroughly before planting.

If this is fresh, get it in there now. But mix into the soil. Must sit 6 weeks or so after mixing before planting. If you plant with fresh manure, you will burn the plants. If it composted (out of a bag, or sitting in a pile for months) then add it anytime prior to planting.

Mix with an equal volume of dirt, the ammonia will burn and kill your plants. It has to set and be odorless before planting.

http://homeguides.sfgate.com/apply-cow-manure-beds-43287.html