We calve spring and fall. Spring is mid March this year, til about June1st so trying for 75 days. Bulls didn't go in until June this past year due to several reasons. Usually try for mid May for the bulls to go in. I am so glad that we didn't now, looking back at the weather we have had these past several weeks.
Fall is usually Oct to Dec 1st. . Try to get them on the ground before Thanksgiving. Since we buy some breds every year, often "one and done" older cows that we can find cheap. That skews the "calving seasons" some. But I hate calves in late Dec/Jan/Feb because we get so much cold wet rain and snow/sleet crap.
We are actually looking at moving the "spring calving" up a little more, to start in April, and not weaning until January, holding them 45-60 days and selling in March. So the calving seasons will be "closer together" but will give us more calves for the spring sales. Unfortunately, we had alot more than normal open cows this fall, so the spring calving numbers will be down, and many went back with the bulls this fall and we hope they will be Sept/Oct calvers. Since it was widespread over all the different pastures, and some cows did not gain like they should have, and most all are 3-4 the calf cows, and cull prices were in the tank, they are getting another chance. Pulled their calves, and then they have no reason not to gain and breed. We'll see. I will be totally intolerant of any that come up open again.
Also try to calve the heifers in the spring, as they just seem to do better with a calf in the nice weather. But we have 17 due this fall as we were trying to move some around, and it just wasn't convenient to breed any last summer to calve some out in the spring. We may be cutting our numbers some too, having lost a couple of rented places, and selling more sq bales of hay. We'll see how things go this year.
Another thing, the black buzzards are real bad in the spring compared to the fall, so it might be a better deal to calve these heifers in the fall this year.