First you need your ph right - not just guessed at. Alfalfa is very fussy about that.
It wants enough P (& K as well) so as long as you are getting soil test for ph, get the P & K tested as well.
Add the lime you need as soon as you can. Add up to 4 years worth of P (if you can afford it, can run $50 plus an acre) to be there for the alfalfa.
Alfalfa wants to be planted 1/4 inch deep, firm - very firm - soil packed around it (but not compacted - just firm!), and it wants to be kinda wet until it gets a good sprout & growing. It does not like wet roots tho so not in wet type soils. It also does not like sand - partly because P doesn't stay in the sand.
Boron is a micro nutrient it likes, that can be figured out on the soil test as well & added with the P fert.
Typically one can plant early in spring, or early in fall & get a good stand of alfalfa. Either time is typically right before a rainy period. Do not plant in the heat of summer.
Old alfalfa plants in the field needs to be killed deal for at least 3 months of good weather - prefer a year. Alfalfa puts out a toxin in it's roots that kill young seedlings. This is for real.
Spring planted, typically weeds come up and get you. Also erosion if you are on any hill at all. It is good to plant 2 bu or so of oats along with the alfalfa as a nurse crop. It will sprout up & hold the soil from water or wind erosion, keep down the weeds a bit. You can cut the oats before boot stage for an early hay crop, let the alfalfa go to town after that. Can often get 1 cutting of alfalfa if you harvest the oats for grain; 2 cuttings of alf if you cut the oats off early.
You can seed without a cover crop, might need to spray for weeds and there aren't so many good sprays for weeds. Alfalfa will come through a bit stronger tho if you don't have erosion problems.
Fall planting, get it planted 30 days or a bit more before first frost. Less weed problems, often less erosion chance as well. Don't harvest in fall.
Firm seed bed, very shallow planting, moisture after it's planted, and enough P are some keys to a good long stand of alfalfa.
--->Paul