There are a couple of ways to do no til
One way actually requires you to double dig or till the first time.
I would get a soil test done first. Send it to your local extension service office. The master gardeners can help you with the results. Request organic recommendations and say it is for a mixed vegetable garden or if you are going to plant a single crop than say it is for corn or whatever you are planting. The test may take a few weeks to come back, but it will tell you hopefully by 100 sq ft not acres, how much compost manure, bone meal, etc you need to add.
Another way is to divide your garden space into beds. You have a 25x50 foot space. You can do 8 raised beds, each 25 ft long and 4 ft wide, with the remaining 32 ft for pathways between the beds (about 3 ft wide which would be enough to get a cart or wheelbarrow or two people side by side to walk through. To do the raised beds you would mark out the borders and you can build the bed walls with stones, tiles or wood. I use hollow tiles. They are easy to dry lay with rebar and dirt to anchor them and less trouble than stones to weed and you don't need to worry about rot. Because they are dry laid, they can be easier to repair since they are not glued in. To save costs, you do not need to have any border at all, just hill up the sides and raise a mound about 8-18 inches high. All the prep that would be needed would be to fork the soil beneath to open it up and allow water to flow through and then build a lasagna raised bed on top of it by sheet mulching.
https://extension.oregonstate.edu/lane/s ... osting.pdf
If you want to do a 25x50 ft garden without the raised beds, you still would need some kind of pathway to weed and a place to walk to harvest. I have seen people plant every square inch, but I could never figure out how they managed to not step on something, I can't do it. if you are going to do that big an area. I would rent a tiller and till it just once and while you are at it till in 4-6 inches of compost and about 40 lbs of composted steer manure per 100 sq ft. One bag of steer manure is about 1 cu. ft and weighs about 25 lbs, so about 25 bags of composted steer manure for that size plot.
If you can find a bulk supplier, compost is cheaper by the truckload.
You don't want to use fresh manures, but if you are willing to compost it yourself you can probably get a lot of that for nothing or cheaper from stables, piggeries, chicken farms and dairies. Just do not use it fresh. It may burn plants and fresh manures need to be hot composted or aged to make sure they are safe for edibles.
Even if you do a green manure, the soil still has to support the plant and have some nutrients in them. Most fallow plots
will support a first crop as long as it is not a heavy feeder. You still would want to add a layer of organic matter on top and you will need some nutrients if your soil is lacking. No til will take longer to incorporate the organic matter in the beginning so it is best to at least consider at least one till to incorporate organic matter and nutrients to get it off to a better start. It may take a couple of years of no till, to get in the groove and get the garden to really start to produce well. But that is true of most organic gardens starting from scratch, it takes about 3 years to build up the soil web to really see good production.
https://www.hobbyfarms.com/crops-and-gar ... ening.aspx
To prep the soil for a green manure, you should make sure it is weeded first and more or less leveled. If you are going to put in an irrigation system. This is the time to work it out. Run the beds north south with at least 6 hours of sun during the growing season.
Fork the ground with a garden fork to loosen and allow the water to get through it. If the soil is really rock hard and dry. You will be better off watering it deeply first. It will make it easier to fork through it and loosen the soil easier. Make sure you let the soil dry to a friable stage before you work it again.
Cover crops you can use are
Buckwheat - about 6 weeks to maturity cut it down when it starts to flower. Adds biomass
Sorghum/Sudan Grass will add lots of biomass, smother weeds and helps to loosen compacted soils and is heat and drought tolerant and will be killed by winter so it will decompose and be ready to plant in spring.
https://www.uvm.edu/vtvegandberry/factsh ... ngrass.pdf
If you want to add some nitrogen fixation it is best to inoculate the seeds first. Nitrogen fixation is misleading as these crops and the bacteria use nearly all of the nitrogen that is fixed for themselves. In fact legumes require a lot of nitrogen if nodulation is poor to get a good stand. It is only after the plants and bacteria are killed that they slowly release the stored nitrogen to help the following crop. What people do not understand is that if you are using soy beans or cow peas for a green manure, they have to be tilled in or cut down when they flower. If they are allowed to make pods the nitrogen is transferred to the pods and if you eat the pods, the soil never sees that nitrogen. If the legumes are not inoculated and the soil has poor native rhyzobacteria populations then nodulation will be poor and you will not get much nitrogen fixation but you will still get biomass added.
Sun hemp is another popular cover crop that breaks up hard soils, adds biomass, fixes nitrogen and as a bonus deters nematodes. It is used mostly in the tropics and the Southern States.
https://edis.ifas.ufl.edu/ng043
https://www.public.iastate.edu/~teloynac/354n2fix.pdf
https://www.ext.colostate.edu/pubs/crops/00305.html
https://www.johnnyseeds.com/c-217-inoculants.aspx
https://www.johnnyseeds.com/p-9113-sunn- ... -sunn.aspx
With the cover crops in no till, you would cut them down to stubble, let the frost kill them or basically roll them down to form a green manure mulch and plant through it in the Spring.
