How can I clean mildew and dirt out of concrete?

Hi Donna, Use Wet and Leave or Spray and Leave etc. available online or at good stores.......

Hello! We are trying this product for the first time that we saw on Todays Homeowner—on our house siding called wet and forget - outdoor and that the product works on mold and mildew problems - seems to be pretty effective you may want look into it and see if it’s a product you may want to consider.

We purchased the hose end formulation to spray our two story home without a ladder and it covers 2000sf for about $37.00.

Please look over link, reviews and Q&A to see if it’s a product of fits your needs as well as review the appropriate product size you need to purchase.

Heres product info to get you started.

WET & FORGET CONCENTRATE

MOSS, MOLD, MILDEW & ALGAE STAIN REMOVER

Are you tired of the never-ending cycle of cleaning black and green stains from your home? Introducing the easiest solution for eliminating these issues without using elbow grease or harsh chemicals—Wet & Forget Outdoor Cleaner! Simply spray and walk away! That's it. Wet & Forget goes to work with the wind and rain to gently clean the surface over time.

• Easy Spray & Leave Application
• No Scrubbing, Rinsing or Pressure Washing
• Bleach-free, Phosphate-free and Non-acidic
• Surfaces Stay Clean 1+ Years in Most Cases
• Safe for Virtually Any Outdoor Surface

https://www.wetandforget.com/wet-and-forget-concentrate.html

Try mixing bleach and water and power wash or let sit and hose down. Make sure run-off is out of reach of children and pets.

I'm a Donna,too

Nice to meet you!