I would recommend a cover crop, nurse crop, of oats or preferably winter rye, because the clover you are planting will not amount to much until next spring. The cover crop will provide some forage and an attractant to your plot this fall. Next year the rye will die off leaving what should be a great stand of clover and chicory.
Cover crop of oats and rye will be a huge plus IMO. Something green in the plot for the deer to eat this fall while cloverlings get established, oats will die with frost, but rye will continue to grow and be the first green the deer have next spring. Then as the rye takes off in spring, it will further protect your young clover from browse pressure until it can withstand it on it's own. Mow or spray the rye with cleth to terminate it and release the clover. Or you could just let the rye mature and drop seed to get a volunteer crop of free rye the next summer, but that is another story.
That is way too late for a good clover plot. Winter Rye or Winter Wheat is ok that late, but a late summer plot of clover in early July will develop into an acceptable clover plot come fall. Granted I do not know what state you are in but for Minnesota you got to have that clover in earlier for a good plot.
I am in southern Nebraska. Planting anything here in July or August is a waste of time and money unless it is irrigated. I know the oats will winter kill here, it is planted regularly around here for various purposes. I am just not familar with rye as it is not grown around here. Winter wheat is probably a comparable crop here to rye. Oats would definitely be cheaper. Dont care much about any green up other than the clover and chicory come spring. Our deer densities are currently low.