Featured | For Gardeners

Pro Mix Potting Soil vs. Miracle Grow Review

Sharing is caring!

This year, I decided to try Pro Mix Potting Soil vs. Miracle Grow Potting Soil for my 2021 garden. Back in 2020, I got serious about gardening. The pandemic inspired many new gardeners to try a quarantine garden, and while I wasn’t new to gardening, I definitely dove back in head first. But after planting SO many seeds indoors, I noticed tons of gnats. So, I decided I needed a change from Miracle Grow Potting Mix.

I asked about favorite potting soil brands in one of my Facebook gardening groups and discovered a lot of gardeners actually don’t strictly use Miracle Grow potting soil! Some mentioned Black Gold soil and others mentioned FoxFarm.

Some serious gardeners talked about how they make their own DIY potting mixes every year. It sounds like it works out cheaper and involves a true labor of love!

Numerous recommendations poured in for Pro Mix Potting Soil, so I decided to give it a whirl.

ProMix Potting Soil Review vs. Miracle Grow Brand
ProMix Potting Soil Review vs. Miracle Grow Brand – Big bag of compressed Promix soil on our stone walkway

What is Pro Mix potting soil?

Pro Mix potting soil is peat-based potting soil designed for indoor and outdoor plants as well as seed starting and other garden needs. The ingredients are carefully selected to support vigorous growth, better moisture management, improved nutrient uptake, larger root systems, and healthier plants overall.

What is in Pro Mix potting soil?

The Pro Mix moisture mix contains Sphagnum peat moss (80-90%), natural coco coir fiber, perlite, ground limestone (for pH), mycorrhizae, and an undisclosed wetting agent. The organic garden mix contains a bit less peat but also includes Gypsum. Meanwhile, the Pro Mix All-Purpose Mix includes Canadian sphagnum peat moss, peat humus, perlite, limestone, and mycorrhizae (PTB297 technology).

What's in Promix potting soil - peat based potting mix
Promix potting soil is a peat based potting mix.

Benefits of Pro Mix

I loved Pro Mix soil from the first time I tried it this year (2021). It is now my go-to potting mix for the foreseeable future.

Here are the best benefits of Pro Mix Potting Soil:

  • Clean – From the first time using it, Pro Mix Potting Soil just felt cleaner and higher quality than any other potting mix I’ve used to date. The mix just didn’t feel as dirty as traditional potting soil.
  • Affordable – The bag of Pro Mix ended up costing me about 40% less than the equivalent amount of Miracle Grow Potting Mix. The 2cu ft value pack saves money and includes a LOT of potting mix!
  • Compressed – Two cubic feet of potting mix fit into that bag of Pro Mix! It’s packed in tight to take up less space. The compressed potting soil limits packaging, resulting in 2x less bags per package.
  • Convenient Package – The convenient packaging has a sturdy handle and a boxy shape that fits well in storage when not in use. The Pro Mix bag also holds its form after opening, keeping your garage and other spaces neat.
  • No Gnats – To my pure delight, I didn’t notice any fungus gnats, fruit flies, or other pests emerging from the soil. It’s been amazing, to say the least.
  • Recyclable Bag – It’s always great to see a company making an effort to a greener lifestyle!
Holding some Promix Potting Soil to Show the texture and what's in Promix soil
Holding some Promix Potting Soil to show the texture and what’s in Promix soil

Where to Buy Pro Mix

I purchased Pro Mix Moisture Potting Mix (with the dark pink label) at the Pottstown Walmart two or three times now. It was not in stock at the Bechtelsville Walmart, but I will check there again in the future. It is difficult to find during the off-season (late fall, winter).

You can also check your local hardware or home and garden stores, like Home Depot and Lowes, as well as Amazon.com. If you go to ProMixGardening.com, you can also search for a store near you.

Pro Mix Potting Soil vs. Miracle Grow Potting Soil

In my experience comparing Pro Mix Potting Soil vs. Miracle Grow Potting Mix, I found Pro Mix to be the superior product. For years I’ve used Miracle Grow potting soil and I will continue to use it here and there. As far as indoor gardening and seed starting, though, I will rely on Pro Mix as long as it’s available.

Lovely texture of Promix Potting Soil in a nursery pot with a green spoon
Showing off the lovely texture of Promix Potting Soil in a nursery pot with a green spoon

Here’s the breakdown of Pro Mix vs. Miracle Grow potting soils:

  • Cheaper – Pro Mix wins this category as the 2 cubic foot bag of compressed soil was only $12.88 at Walmart. Looking at Lowes or Home Depot, I’ve seen the same about of Miracle Grow mix for close to $20.
  • Better Quality – I enjoyed the texture, composition, and cleanliness of using Pro Mix potting mix far better than the Miracle Grow mix. As I write this, gardening season is currently over here in PA Zone 6b, but I can’t wait for seed starting to run my fingers through the mix as I plant tons of seeds all over again.
  • Value – I feel that the amount of Pro Mix provided in the compressed packaging is very fair for the cost and happily continue to be a repeat customer for this product. When Miracle Grow potting mix goes on sale, I will happily still buy it for my outdoor garden beds and containers.
  • Purity – When comparing Miracle Grow potting mix to Pro Mix potting soil, I felt the contents of both seemed to have good purity. However, I liked the look and feel of Promix better and also found less trouble with soil gnats (fungus gnats?). Promix may also be a good option if you are trying to avoid fertilizers already being included.

Sometimes I struggle with maintaining proper moisture for young seedlings. I don’t think I had as much trouble this year using the Pro Mix Moisture potting mix, but I’ll try it again for next growing season and report back.

Promix potting mix in a nursery pot - here's my review of this potting soil.
Promix potting mix in a nursery pot

Truthfully, I do like both brands and would happily use either in seed starting, filling flower pots or containers, and amending outdoor raised beds as needed. Both companies offer quality products, and it was a nice change trying a previously unknown, new brand and product.

What’s your favorite potting mix? Have you tried the comparison of Miracle Grow potting soil vs. Pro Mix potting soil?

Shout out in the comments below so we can track everyone’s favorite brand and experiences!

Happy Gardening!

Similar Posts


  1. I started using ProMix last year and I am hooked. Exactly as you described in your article. I believe Miracle Grow is messing with consumers and offering an inferior product while rebranding the good stuff and charging a higher price…no good. ProMix is my go-to potting soil for now. I’m exploring Coast of Maine via Amazon. Bought couple of bags when there was a price drop but haven’t used it yet.
    Thanks for a good article.

    1. Hi Helen,
      Great to hear from you! Thanks for taking the time to share your experience and comment. I am so in love with ProMix and will continue to buy it. I hope others will give it a chance. I haven’t tried Coast of Maine but will look into it and would love to hear your thoughts on it after you try it. So glad you liked the article – thanks for the feedback. Always makes my day when I hear from someone like you who took the time to drop me a line. 🙂 Happy Gardening!

Leave a Reply

Your email address will not be published. Required fields are marked *