Since I have moved, we are plotting our new gardens and they happen to be in hay fields.
Our main vegetable garden is going to be 125' x 75' and we will also have a fruit garden that will be about the same size to start.
I have cut down the hay in two different areas for the gardens and am left wondering if a tiller will break the ground?
I have tilled many gardens for myself as well as for clients with a Troy-Bilt horse tiller. All of them were either existing or I had to till in the sod from lawns. This hay seems to have a pretty deep root system. I am wanting to hire someone to do the initial tilling with a tractor/ tiller and I will maintain it with my tiller afterwards. Will a large tiller do a good enough job breaking this stuff up or should I look into different options?

Check craigslist and get someone with a 30+ HP tractor / tiller to break the ground initially. It would be around $100 in my area. I did that with my garden 4 years ago. It was a 1/2 acre and used to be corn/soybean field. I had it tilled with a big tractor the first time, second year I did it with a Troy built, and last year I bought a small Deere 665 and a tiller. Our garden now is 4 plots and just under an acre.

I am waiting for someone that is a friend of a friend to come check it out.
He has a larger tractor/ tiller and also does field maintenance.
I actually own a John Deere compact utility with a few attachments but never got a tiller for it. I guess it's time to start looking for a 5' tiller for sale.
Sounds like you have some huge gardens. Pics?

I do about 1/2 acre combined on my 2 plots with a Troybilt horse (1971 vintage by the casting code).

Previous owner used it on a 5 acre truck farm as his only cultivating device (no tractor) for 20 years before I bought it off of him when he retired (tough old WW2 type that did not like to slow down for shit, but his body was failing him).

It's currently on engine number 4 and nothing other than the belts / tines have ever been changed.

I'll post some pics when I get home. On the iPad now. If you have a CUT, check the local rental house. You can probably rent a 5' tiller for under $100.

a 5' tiller is $1500 or more
and they get beat up.  (esp on virgin ground)
hire someone off craigslist and let them beat up their tiller for probably $100 to $200

I could make two passes (90 deg to each other) at about 1/2 acre an hour with a 5' tiller and tractor.

I am going to have someone else do the initial ground break/ till and I will maintain it with my Troy-Bilt. After it is fenced in I will probably do what I did in my last garden, I added about 6"-8" of hardwood mulch. This greatly reduced weeding, watering and kept the soil soft and well fertilized as it broke down.
Eventually I will switch to composted woodchips as they are free and I now have the space to store as much as I want.

Pay a farmer to plow & disc it first.  Then come back with a tiller. Tillers are not designed to open new ground, you need the depth of a mold board plow to invert the soil & kill the turf.  Otherwise you are just mixing it up & you'll fight massive weed growth for the next several years.

+1 on the plow/disc.  I think you'll beat the heck out of a PTO tiller, or yourself and a walk-behind...

Yep.  PTO tillers are hard on the tractor but if they aren't too bad if the ground is plowed up and disked first.

I've been using a Tarter 5 foot tiller for the last couple of years, and it works well.  I only wish I had gotten a 7 foot tiller instead.  

This spring I tilled up about 2.5 acres with it.  So far I have done no maintenance other than putting grease in it.  It has jumped over a lot of hidden stumps without damage, and it does a good job of chopping up rotten wood and palmetto roots.  On new ground I drag a subsoiler through it a few times to find stumps and large roots.

Sounds like you have a good plan;

pay someone to turn it over with a plow as it's overtasking a regular tiller.
maintain with a tiller on your own or rent one/pay a guy.  

I kept getting the same advice to not invest in a tiller and to pay.  I bought one anyhow and it should be in withing the week.  I bought a KK 5' tiller for my 32 hp tractor.  

I just feel better to be a bit more independent by having the equipment.   I plan to till in the fall too.  I have to start amending in a fair amount of organic matter to my mostly rock mineral soil.

good luck and happy growing!

Plow it, but then you are ready for a tractor tiller.

In the way back, an 8' Kuhn was used in the hayfields after plowing.  The idea was, a tiller will get the soil 100% in one pass where a 16' disc might be wider, you need 3x the passes to get the dirt broke down.

Maintenance heavy when you are working 40 acres of hayfields

I've used a tiller to manually till an area about the size you are referring to and I've also done it w/ a disc on the back of the tractor.  Using the walk behind tiller, you'll have to make multiple passes, starting really shallow and going to full depth.  IIRC, I made three or four passes before I was finally satisfied w/ the break up of grass/weed roots.  First pass was N-S, second was E-W, then NW-SE and NE-SW.  Took a long time to go from grass/weeds to tilled well enough to plant in.

For your tractor, just go get a 4'-5' disc.  No need for a tiller.  The first year, it will take a while and you'll want to use a similar method to what I described above.  After a few years of discing, you'll want to use a bottom plow to break up the hard pan that develops under the area that you disc - 12"-18" down.