Yes, probably. Pretty much any fertilizer label will tell you not to apply if heavy rain is expected.

 

Looks like you're in Atlanta, so you know how it is with these late day summer storms. They pop up out out nowhere.

I finished spraying fertilizer around 5:00 in bright sunshine. Ten minutes later, wind starts blowing and suddenly the bottom drops out. 6:30 I'm back outside picking up limbs and sweating in the sunshine wondering if $30 worth of fertilizer washed out. 🤷‍♂️

 

That’s a lot of rain to come down! If you have a flat lot that doesn’t have too much slope, I imagine you didn’t necessarily lose the fert. Depending on fertilizer type, you may have had it all solubilize though, at the least.

 

I just read where you said you applied it in liquid form. I missed that part. That would make me feel better about the downpour, at least you’re not seeing pellets of fertilizer rolling off site! I am curious, how are you putting that much liquid nitrogen down? I imagine 2-gal/1000 minimum (?)

 

I have a 5 gallons of liquid that is 32-0-0 with 2% FE. Fast release. It works out to be about .23 Lbs N per M in 6 ounces of liquid. I put 83 oz in my 4 gallon sprayer then topped of the rest with water.

I’ve calibrated my sprayer and my walking speed over the years and gotten to where I can consistently and evenly cover everything in my lawn with 3 tanks. I don’t care so much about the water. I just put in enough product to cover 4600 sf, top off with water, and go. I’ve got about 14k sf of turf.

There are more economical ways to do this but I have this liquid on hand. Usually I use it to spoon feed but after verticutting I wanted to give it a boost.