Talk to the folks at Farm Credit, Farm Bureau Bank. Farm Plan, your feed and supply store, and also at FSA. FSA has some loans of last recourse, meaning you got to get turned down somewhere else first. Also, talk to local small banks, the majors in my expereince wont play. Two examples.... I needed a letter of credit for planning and zoning on a subdivision road. Relatively straight forward, I pledged a CD as security. Ended up costing me 3% of the value of the letter to get them to write it to use my money as a pledge that was paying .5%. It took a local bank to write it for me, still charged me 1%.... Finally got P and Z to just hold a cashiers check on me.
I'd not worry about having everything ready up front, go talk to them. See what kinds of paper work they want. No use working and getting all kinds of statements and stuff together if they want something else or something specific.
The other option is private paper. Its out there. With today's low interest rates there are a lot of individuals who are loaning money to private individuals. It's not the low bank rates you see on first mortgages but remember, over half of all Americans carry no debt. Its called many things, venture capital, private paper, etc. Look to pay a premium rate, sometimes very premium, but its out there. Right now I'm seeing rates from a low of 10/11 % for first mortgage loans up to 28% for small personal loans for things like bail and utility bills with secured vehicle loans somewhere in between.
Lastly, don't rule out credit cards. There have been a world of businesses started using them. While the offers arent as generous as they once were you can still get a credit line opened up there. Make the minimum monthly payment and then pay off at harvest.