13-13-13 fertilizer questions

Triple 13 is good for your trees and shrubs. What type of grass do you have? I'm assuming centipede or st aug. 13% is a bit low for nitrogen and bit high for phosphorus when it comes to a lawn fertilizer. Yes, you can adjust your spreader to apply more nitrogen but you'll also go through your bag of fert faster and with it you will also be applying more phosphorus. For centipede I like 16-0-8 and for st aug I like 25-3-5.

3 good nitrogen ferts a year is a good starting point for your lawn.

I use a lesco spreader so I can't tell you where to set your Scotts spreader. You'll have to do the math. How much product per thousand square feet does each spreader setting put out plus the percent of that product that is nitrogen. Right now I would put down 1lb of nitrogen per thousand square feet.

Yes, too much fert can burn your lawn. Too many factors to give you an exact amount. Plus overfertilization can make a fungus explode on your lawn.

Great stuff thanks. How long should I give trees before I can see a difference the fertilizer made and if I need to add more?

Trees are very frail and thin so it shouldn’t take long to see a difference I would think.

What about for Zoysia?

That is going to depend on the growth rate of the trees/shrubs. You should be able to tell a difference in flowering trees/shrubs the next time they flower. You should notice more budding going on. Do you have lichen on any of the trees? I like to use that as a guide for how my fertilization is going.

Fertilization wise zoysia is going to be treated more closely to centipede.

Lichen isn't horrible but it usually means the tree is deficient in one or more nutrients. I break of the lichen and if it doesn't return then I call the fertilization a success.

It's not going to hurt it but all of that phosphorus will end not being used.

Thanks for the response. As long as it won’t hurt, I am not worried about the phosphorus being unused. Appreciate it!