what is a good ph level for the soil? what fertilizer should be used, and how often?
We have just that articles for you! This one will help you to know what they require in container:
https://www.gardeningknowhow.com/edible/vegetables/asparagus/potted-asparagus-plants.htm
These articles will offer much more useful information on Asparagus and its care:
https://www.gardeningknowhow.com/edible/vegetables/asparagus
My asparagus crop is almost 10 years old. I fertilized it in the winter after the greens turned a golden color--and I cut them down. I put some leaf mulch down also for the winter. Now I have a big crop, but its all extremely thin. Too thin to eat! Should I cut these down now--hoping the plant will have more energy for the remaining growth--or should I just wait until the season is over and thin out the crop. I'm devastated! I'm in western Pennsylvania. Thanks!
If you've been successful this long with your asparagus, it seems that they may have reached their peak in age. Here's our article about asparagus that's too thin:
https://www.gardeningknowhow.com/edible/vegetables/asparagus/thin-asparagus-spears.htm
Another suggestion is to contact your local agricultural extension service with the question. They should be able to help. https://www.gardeningknowhow.com/extension-search?zip=16226&radius=10&extservsearchaction=search&submit=Search
I just don't know if I should cut the ones off that come out as a small fern? There are some normal ones to which we have had a 4 but they seem to be more of the fern ones. Not sure if I should cut them or not to throw away.
It sounds like it is "ferning out." Wait till fall to cut all the foliage back.
https://www.gardeningknowhow.com/edible/vegetables/asparagus/asparagus-ferning-out-early.htm
I have a 8'x4' box used some time ago for asparagus. I would like to add more soil but don't want to lose the asparagus. Can I add ~3" of soil over the asparagus or should I move it and replant after adding the additional soil? I already get your newsletter and find it most enjoyable and very helpful.
Research indicates that it's okay to put this much soil over existing asparagus crowns. I don't know if it will affect its rate of growth, but it probably won't have a negative effect on the plants themselves, as long as the proper growing conditions are maintained.
I live north of the 45th parallel and had an established bed of Asparagus but not doing very well, over grown with lots of grass. Transplanted it to a raised bed last year and it seemed to improve. However i have not seen any sprouts yet this spring. Did it freeze out because of it being in a raised bed?
It's hard to speculate about this. I don't know how deep your beds are or how deeply you planted your asparagus. It may simply be adjusting to a new environment. Asparagus can tolerate some pretty cold climates.
Here's an article from UMN that may be helpful:
https://conservancy.umn.edu/bitstream/handle/11299/198098/Asparagus%20production%20guide.pdf?sequence=1&isAllowed=y
and a Gardening Know How article, as well:
https://www.gardeningknowhow.com/edible/vegetables/asparagus/winterizing-asparagus-beds.htm
I moved to a house with a mature vegetable patch. The asparagus crop has faded over the last 2 years and has now almost finished. What should I do with the bed? Can the crop be revived?
There is quite a bit of maintenance that goes into caring for a patch of asparagus. These articles will help:
https://www.gardeningknowhow.com/edible/vegetables/asparagus/growing-asparagus.htm
I was wondering if I could put up a border and put more dirt around the ferns at the base to make it deeper or if should just leave them alone?
You could do either, but I would add some backfill. This article will help you to grow asparagus:
https://www.gardeningknowhow.com/edible/vegetables/asparagus/growing-asparagus.htm