Make sure to throw in plenty of potassium and potash. Root veggies require it big time. Frankly, I'd use Garden's Alive - Root Crops Alive!™ Fertilizer
All-natural fertilizer provides the extra minerals root crops need
Root crops—such as onions, beets, carrots, potatoes and turnips—need the support of soil that’s rich in potassium and phosphorus. So we’ve packed Root Crops Alive! ™ with these essential nutrients in just the right balance needed by root crops. And, unlike greensand-based fertilizers, the potassium in Root Crops Alive! is plant based, so root crops benefit immediately. Apply 2-3 lbs. per 100 sq. ft. when you prepare the soil, or side-dress when plants emerge to get greater coverage per pound. For best results, feed again in midseason.
That's a beaut of a row of taters. But wait till you taste!
Get me some shallots and duck fat,... QUICK!
Dang!