Okay, so I’ve been getting into gardening lately, and I heard about this thing called “basic slag fertilizer.” Sounds kinda weird, right? Like, what even is slag? But apparently, it’s good for the plants, so I figured I’d give it a shot. I’m all about trying new things in the garden, especially if it means bigger, healthier veggies.
My Basic Slag Adventure Begins
First things first, I needed to figure out what this stuff actually was. Did a little digging online (pun intended!), and it turns out basic slag is a byproduct of steelmaking. Who knew? It’s full of phosphorus and other minerals that plants supposedly love. Sounded promising, so I ordered a bag online. I think it was, I don’t know, pretty cheap for a big bag. Seemed like a good deal.

When the bag arrived, it was heavier than I expected! Seriously, I almost threw my back out lugging it to the garden shed. Note to self: lift with your legs, not your back. The stuff inside looked like dark, gritty sand. Nothing too exciting, but the magic is supposed to be in the minerals, not the looks, I guess.
Getting My Hands Dirty
Next up, time to actually use this stuff. I read somewhere that it’s best to apply it in the fall or winter, so the nutrients have time to break down and get into the soil. Since it was late fall, perfect timing! I have this one raised bed where I’m planning to grow tomatoes next year, so I decided to test it out there.
I basically just sprinkled the slag all over the soil. I didn’t really measure anything, just eyeballed it. Probably used about a handful per square foot, maybe a bit more? It’s not an exact science, at least not for me. Then, I took my garden fork and worked it into the soil a bit, just to mix it in. I do it like mixing flour into cake batter, get in there.
The Waiting Game
And that was it! Now, it’s just a waiting game. I won’t really know if it works until next spring when I actually plant the tomatoes. Fingers crossed this slag stuff does the trick and I get a bumper crop of juicy, red tomatoes. It has a very long wait, like months before I see if I get some big, beautiful maters’. I’m so excited.
- I will continue to observe the soil to see.
- I will add some basic slag fertilizer around my flowers next week.
I’ll definitely update you all next year on how the tomatoes turn out. If the basic slag works, I might just have to use it on all my garden beds! Wish me luck! Stay tuned to see if my tomatoes are giants or duds.