How many breeding cows realistically would you recommend on 21 acres - that's how big another property nearby is. That would be much better!
About 3-4? Plus calves?
We have about 18 acres of grass; we have three breeding cows and a bull; currently two with calves at foot and one due end of July. We have four steers at another smallholding - 2 2018 and 2 2017.
The older pair will be away October and will be replaced by two 2019 steers at weaning, either homebred (we have one steer calf at the moment) or bought in from another pedigree breeder (we always have two to a) meet out customer demand and b) so that two go to the abattoir together).
Any heifer calves are halter trained and sold over the winter.
We house on 1st November and turn out 1st May, more or less. We buy in hay.
Our soil is sandy but with a very highwtartable so is liable to flooding if there's a lot of heavy rain in a short period.
We also run about 10-12 breeding ewes; lambs away mid October. And three ponies
In a good year, with good grass growth, we're fine. Last year,we were pushed, fed hay in summer and there was a bit of overgrazing.
Hope this example helps.