Late summer or early fall is the recommended time and compost or composted manure is just fine to use. So do it now :-) Don't wait until after cutting back the ferny tops. They should stay in place until they brown and start to dry up, typically after the first frost

I wouldn't use fresh manure at either time. Well composted manure can be applied in the late fall after you cut back the ferns. Just top dress with it followed by a few inches of shredded leaves.

I usually feed my gus beds 3 times a year with 13-13-13. In the early spring before new growth (March here), after I stop harvesting (June), and then again about now (before a good rain is forecast). Then I apply about 1-1.5" of finished compost after I cut the ferns (November) followed by the shredded leaves

I should have made something clear; I don't have access to composted or fresh manure so I'll be using the store bought. I do have compost from my tumbler that I can also add. I will work on adding the manure and compost as soon as I get to the store, then do it again in the early spring. I have been adding are spent coffee grounds as well.

I need some more advice. I found a fertilizer that was 13-13-13 and came in 40 lb bags. My beds are 4x4 and 12 inches deep. How far would 40 lbs go and is $14.00 a decent price? They were also selling Black Cow compost/manure but it was .5-.5.0.4. Would that be enough for asparagus?