What Works Faster: Milorganite or Ironite?

This is another question that showed up in my search results--apparently Milorganite and Ironite are frequently compared head to head.

They really shouldn't be as they're completely different things.  Milorganite is an organic feeding that happens to contain a large percentage of iron.  Ironite contains a large percentage of iron and happens to contain a very tiny amount of nitrogen.

As far as speed of greening, both Milorganite and Ironite will give essentially identical results.  Enough of the iron is water-soluble that it'll reach the roots at about the same speed for each product after watering in (or rainfall).  While Ironite has a bit more iron, it's not significant at bag rate applications.

As far as feeding, Ironite will give a tiny boost of nitrogen.  Milorganite will give a much larger one (there's ten times more nitrogen in Milorganite), and about two-thirds of the nitrogen in Milorganite releases over the long term.  Organic nitrogen requires time to decay, process, and become available to the plant roots.

Milorganite will help enhance your soil over time as well, although the process is rather slow--on the order of years, not weeks or months.

If you read my posts from this weekend, Milorganite is the heavy-hitter in my gardens (and often in the lawn, although less so this year).  Ironite...I don't use the stuff, personally, as the unit price is more expensive when comparing both the iron and the feeding capability of Milorganite.  Add in the soil alterations and there's no comparison.  It's Milorganite hands down!