7-0-20 summer lawn and turf stress granular fertilizer blend (with bio-nite 45lb bag - covers 15,000 square feet - 7% nitrogen - 3% iron - 20% potash - safe for all lawns - apply all year round yard mastery bio-nite is an all natural bio-solid; the same thing as milorganite but instead of being mined from the bowels of milwaukee, bio-nite comes from south florida. smells like massive success which lets you know it's working. bio-nite being all natural also means it feeds the soil when you apply, nice! so with stress blend you get the best of the milo along with a whole heaping helping of other nutrients. the high potash is awesome for a stressed lawn as potash helps with water uptake and retention. iron is there to give you some color response on top. it's 3% iron which if you look at a lot of lawn fertilizers sold in stores, they may have no iron or if they do it's 1.5% or less. stress blend also has a stack of micronutrients lawns need including magnesium, boron, copper, manganese, molybdenum and zinc. best times to use stress blend: really, anytime you want a surprising green response without causing a massive flush of growth, stress blend is a smart choice. but more specifically, for warm season turf this is a great early spring app as your lawn is waking up slowly warm season lawns always seem to wake slowly and it's not a good idea of bang them with too much nitrogen when they are awakening from winter slumber. and then again apply stress blend in fall as the lawn is heading into the winter. cool season turf, this is your go-to late spring and summer fertilizer, hands down. combine this with a shot of hydretain and you will have a much better summer for sure. you can also make it your winterizer application as more and more studies are finding that high potash is great for a winterizer.