Bone meal is rich in phosphorus, not potassium.

According to "Growing Great Garlic" by Ron Engeland, (page 64) researchers at the University of California found that fertilization of garlic with phosphorus or potassium resulted in no significant increase in yield, even in soils with very low levels of these nutrients Nitrogen is the key nutrient needed for garlic to grow the green tops, which then nurture the bulbs.

TomNJ/VA

Agree that nitrogen is what you want. Garlic, shallots, leeks, onions, etc. are all essentially leafy vegetables, not root veggies.

Rodney

you want phosphates for root development, calcium too.

We add Sulfur and a .06% Selenium product that we get from
Lancaster Ag. and Sul-po-mag. and ammonium sulfate.

That is 2 different Sulfates. and Sulfur that soil bacteria may or may not turn into sulfate. Didn't on our potatoes this year.

Dave Rogers

You may think I am crazy but I have found the absolute best fertilizer for my alliums is to pee in a 5 gallon bucket of water a few times then water the plants with that. Plants color is the best they have ever been and growth is vigorous too!

Greg