Whitetail Institute Imperial clover is the best on the market, IMO. WI sales all the herbicides you need to spray it, also. I have a stand that has been going strong for 3 years.
The kind that germinates and thrives. The seed is less important than the prep, fertilizer and care. The local ag store clover will work fine if you do your part. I have used WI with good success...but recently I use a blend from Monster Raxx.
tynimiller is absolutely right. If your soil isn't right and it isn't taken care of properly, then no seed will be successful.
any seed that has 35%-50% coating isn't the best on the market. when clients and businesses give me their nrcs orders it's always based on PURE live seed. I have been in the business for 25 years and there is only 1 reason why people sell coated seed. Don't believe me? Talk to the actual growers of the seed and they will mimic my words as well as the nrcs and anyone that is independent and not worrying about price point and the competition. I will have 2 education plots in that will have every clover you can imagine. There will be day 50-55 day post planting forage analysis and sward density measurements. So what is the best clover to plant? Depends on your area in the US, your soil type, is your soil wet? Is the area shady? Is there a high deer density? My background is in managed intensive grazing and i have sold every clover you can imagine, planted them all and had clients planted them all. So, that being said and someone wants a great clover mix that can be planted anywhere? I can't mention my business on here as i am not a sponsor. But i have a seed distribution business and a wildlife business i started to raise money for youth hunters education, disabled youth hunts and wounded veterens. I don't use coated seed and i use a natural growth promoter on all the seed. I buy the highest germ count and low weed seed counts i can find and i also have people growing seed for me in areas around the us. No 1 can make these claims on the market. Don't want to buy from me? I'll be more than happy to give a list of people who i trust, have worked with and who i know also share my philosophy to selling great quality seed and who do it honestly and with integrity. Imperial whitetail clover has berseem clover in it at 35 percent. I love berseem clover but know that is an ANNUAL not a perennial. There mix has 2 ladinos. If it's put in a shady area or wet area you won't be totally happy. Plus check the seed testing date as all seed needs to be tested every 12-18 months depending on your state regulations. I'll stop right there.
I have had great luck with medium red clover and ladino clover. I usually just get my clover from a local elevator-small grains dealer. But as Ty pointed out proper prep is everything.
I have been using frigid forage. Grows great and no fake coating. Pure seed. Went to the coop and they did't have the clover I wanted or maybe they just did care to mix a smaller amount less than 50lbs