Comparison: Best Costco Miracle Grow Potting Mix (Updated | Nov 11th)
Both promise lush, thriving plants, but which one delivers the best bang for your buck? We’ve dug into the ingredients, tested them side by side, and put them to work in real gardens to help you decide—because great plants start with the right soil.
- Best for long‑lasting feed: Miracle-Gro Potting Mix
- Best for water‑smart mix: Miracle-Gro Moisture Control Potting Mix
- Best for eco outdoor blend: Miracle-Gro Organic Outdoor Potting Mix
- Best for vibrant color boost: Miracle-Gro Potting Mix
- Best for gnat‑resistant indoor: Miracle-Gro Indoor Potting Mix
- Best for bulk eco outdoor: Miracle-Gro Organic Outdoor Potting Mix
- Best for premium houseplant soil: Miracle-Gro Houseplant Potting Mix: Fertilized
- Best for rapid seed start: Miracle-Gro Seed Starting Potting Mix
- Best for big‑bloom duo: Miracle-Gro 2 Pack Potting Soil Mix for Container Plants
- Best for compact water‑smart: Miracle-Gro Moisture Control Potting Mix
Product Comparison: Best Costco Miracle Grow Potting Mix
Miracle-Gro Potting Mix, For Container Plants, Flowers, Vegetables, Annuals, Perennials, Shrubs, Feeds for up to 6 Months, 16. qt., 2-Pack
- Miracle-Gro Potting Mix feeds container plants for up to 6 months so you get more blooms for more color (vs. unfed plants)
- How to use: To use this potting medium, fill a container about 1/3 full with potting mix, place your plant in the soil, and fill the rest of the pot, pressing lightly
- What’s included: This bundles includes two 16 qt. bags of Miracle-Gro Potting Mix, each able to fill one 12-inch container (exact amounts may vary based on root ball size)
- Where to Use: Use this home gardening product with all types of container plants, including annual and perennial flowers, vegetables, herbs and shrubs
- This potting soil mix Grows Plants Twice As Big (vs. unfed plants)
Miracle-Gro Moisture Control Potting Mix, For Container Plants, Protects against Over- and Under-Watering, 8 qt., 2-Pack
- Miracle-Gro Moisture Control Potting Mix feeds plants for up to 6 months and Grows Plants Twice As Big! (vs unfed plants)
- This potting medium protects against over and under watering; also absorbs up to 33% more water than basic potting soil* with exclusive AquaCoir Formula (*soil that does not contain sphagnum peat moss, coir, and wetting agent)
- Use this gardening product with all types of container plants, including flowers, vegetables, annuals, perennials, and shrubs
- To use this potting soil, fill a container about 1/3 full with potting mix; place your plant in the pot and cover with more mix
- This bundle comes with two 8 qt. bags of Miracle-Gro Moisture Control Potting Mix; each fills two 8-inch containers (exact amounts may vary depending on the size of the root ball)
Miracle-Gro Organic Outdoor Potting Mix, for Outdoor Container Plants, Contains Quick-Release Natural Fertilizer, OMRI Listed, 16 qt.
- Miracle-Gro Organic Outdoor Potting Mix contains a quick-release natural fertilizer and also feeds plants for up to 2 months
- This potting mix is made with responsibly sourced peat (one hundred percent of peat sourced from certified producers)
- Use this organic potting mix with all types of outdoor container plants, including flowers, vegetables, herbs, annuals, and perennials
- To plant in pots, fill the container partially full with potting mix, place the plant in the pot after loosening the root ball, cover with more mix and water thoroughly
- One 16 qt. bag of Miracle-Gro Organic Outdoor Potting Mix fills one 12-inch container (amounts may vary based on the size of the root ball)
Miracle-Gro Potting Mix, For Indoor or Outdoor Potted Plants, Flowers, Vegetables, Shrubs, Annuals, and Perennials, Feeds Up to 6 Months, 8 qt.
- Feeds all potted plants: Miracle-Gro Potting Mix feeds all types of potted plants, including flowers, vegetables, shrubs, annuals, and perennials for up to 6 months
- Promotes growth: This potting soil Grows Plants Twice As Big! (vs. unfed plants)
- Boosts color: Get more blooms for more color (vs unfed plants)
- Application: To apply this potting medium, fill a container about 1/3 full with potting mix, place your plant in the soil, and fill the rest of the pot, pressing lightly; water thoroughly
- Coverage: Each 8 qt. bag of Miracle-Gro Potting Mix fills two 8 inch containers (exact amounts may vary depending on the size of the root ball)
Miracle-Gro Indoor Potting Mix, Blended for a Variety of Houseplants, Feeds for up to 6 Months, 16 qt., 2-Pack
- Miracle-Gro Indoor Potting Mix feeds houseplants for up to 6 months and is designed to be less prone to gnats (contains no compost or bark, which are known to shelter fungus gnats)
- This potting mix contains coconut coir, which holds and releases water and helps soil re-wet
- Where to use: Blended for a wide variety of indoor container plants, including climbing, foliage, flowering, and tropical plants
- How to use: To use, fill a container about 1/3 full with potting mix; add more mix after placing your plant in the pot
- What’s included: This bundles includes two 16 qt. bags of Miracle-Gro Indoor Potting Mix, each able to fill one 12-inch containers (exact amount may vary based on the root ball size)
Miracle-Gro Organic Outdoor Potting Mix, for Outdoor Container Plants, Contains Quick-Release Natural Fertilizer, OMRI Listed, 25 qt.
- Miracle-Gro Organic Outdoor Potting Mix contains a quick-release natural fertilizer and also feeds plants for up to 2 months
- This potting mix is made with responsibly sourced peat (one hundred percent of peat sourced from certified producers)
- Use this organic potting mix with all types of outdoor container plants, including flowers, vegetables, herbs, annuals, and perennials
- To plant in pots, fill the container partially full with potting mix, place the plant in the pot after loosening the root ball, cover with more mix and water thoroughly
- One 25 qt. bag of Miracle-Gro Organic Outdoor Potting Mix fills three 10-inch containers (amount may vary based on the size of the root ball)
Miracle-Gro Houseplant Potting Mix: Fertilized, Perlite Soil for Indoor Gardening, Designed to Be Less Prone to Gnats, 4 qt.
- Growing indoors is easy under the right conditions; Miracle-Gro Houseplant Potting Mix combines key elements plants need to thrive
- Recommended for growing beautiful indoor houseplant varieties like Pothos, Spider Plants, Monstera, Philodendron, English Ivy and more
- This indoor plant soil is less prone to gnats, thanks to the combination of perlite, sphagnum and peat moss that’s just right
- Certified by the Mulch & Soil Council as a quality product in compliance with industry standards
- A single 4-qt bag fills an 8-inch container; for even more spectacular results, start regular feedings with Miracle-Gro Plant Food 30 days after planting
Miracle-Gro Seed Starting Potting Mix, 8 Quarts (Pack of 2), For Use in Containers
- Specially formulated for fast root development
- Enriched with Miracle-Gro Plant Food
- Excellent for starting cuttings
- Use when starting from seed and with leaf, stem or root cuttings
- This bundle includes two 8 qt. bags of Miracle-Gro Seed Starting Potting Mix
Miracle-Gro 2 Pack Potting Soil Mix for Container Plants, Flowers, Vegetables, Shrubs, Annuals, and Perennials, Feeds for Up to 6 Months, 2 Cu Ft
- BIGGER PLANTS: Watch your container plants flourish with this potting soil that feed for up to 6 months to grow plants twice as big versus unfed plants
- VIBRANT COLORS: Get ready for a spectacular show of more blooms for more color versus unfed plants transforming your containers into dazzling displays
- WHERE TO USE: Perfect for all indoor or outdoor grown containers plants, including flowers, vegetables, herbs, and houseplants
- HOW TO USE: Pick a pot with drainage, fill it 1/3 full with this ready-to-use container mix, add your plant and fill in with more soil, then water; it’s that easy to create beautiful container gardens
- COVERAGE: Each 2 cu. ft. bag of Miracle-Gro Potting Mix fills two 14-inch containers (actual amount may vary depending on the size of the root ball)
Miracle-Gro Moisture Control Potting Mix, For Container Plants, Protects against Over- and Under-Watering, 6 qt.
- Miracle-Gro Moisture Control Potting Mix feeds plants for up to 6 months and Grows Plants Twice As Big! (vs unfed plants)
- This potting medium protects against over and under watering; also absorbs up to 33% more water than basic potting soil* with exclusive AquaCoir(R) Formula (*soil that does not contain sphagnum peat moss, coir, and wetting agent)
- Use this gardening product with all types of container plants, including flowers, vegetables, annuals, perennials, and shrubs
- To use this potting soil, fill a container about 1/3 full with potting mix; place your plant in the pot and cover with more mix
- One 6 qt. bag of Miracle-Gro Moisture Control Potting Mix fills four 6-inch containers (exact amounts may vary depending on the size of the root ball)
Product prices and availability are accurate as of the date/time indicated and are subject to change. Any price and availability information displayed on Amazon.com at the time of purchase will apply to the purchase of this product.
Buying Guide
FAQs
How do I choose between the regular Miracle‑Gro Potting Mix and the Moisture Control version?
The regular mix is a straightforward, all‑purpose soil that feeds plants for up to six months and promotes larger growth. The Moisture Control mix adds an AquaCoir formula that absorbs up to 33% more water and helps prevent over‑ or under‑watering, making it ideal for gardeners who want extra moisture management. Consider the Moisture Control blend if you live in a hot, dry climate or tend to forget watering schedules.
Is the Organic Outdoor Potting Mix worth the extra cost compared to the standard mix?
The Organic Outdoor mix includes a quick‑release natural fertilizer and responsibly sourced peat, providing a more environmentally friendly option that feeds plants for about two months. While it lacks the six‑month feeding power of the standard mix, its organic composition can be appealing for eco‑conscious gardeners and for those growing edibles where synthetic fertilizers are undesirable. The price premium is justified if you prioritize organic ingredients and sustainability.
Which potting mix is best for indoor houseplants and why?
The Indoor Potting Mix is formulated specifically for houseplants, using coconut coir to retain moisture and a composition that reduces fungus gnat attraction by omitting compost and bark. It also feeds plants for up to six months, giving indoor growers a low‑maintenance solution. For most indoor applications, this mix offers the best balance of moisture control and pest resistance.
What are the coverage differences among the various bag sizes?
Coverage varies by product: an 8‑qt bag of the standard mix fills two 8‑inch containers, while a 16‑qt bag of the Indoor mix fills one 12‑inch container. The Moisture Control 8‑qt bags each fill two 8‑inch containers, and the larger 25‑qt bag of the Organic Outdoor mix can fill three 10‑inch containers. Matching bag size to your container dimensions helps avoid waste and ensures you purchase the right quantity.
Do any of these mixes include built‑in fertilizer, and how long does it last?
Yes, most mixes contain a built‑in fertilizer that feeds plants for up to six months, including the regular, Moisture Control, Indoor, and the 2‑Pack Potting Soil Mix. The Organic Outdoor mixes provide a quick‑release natural fertilizer that lasts about two months. Knowing the feeding duration helps you plan supplemental feeding schedules if you need longer nutrient support.
Can I use the Seed Starting Potting Mix for regular container gardening?
The Seed Starting mix is optimized for rapid root development and is enriched with plant food, making it excellent for seedlings and cuttings. While it works for regular containers, it may not contain the same long‑term feeding benefits as the standard or Moisture Control mixes, so you might need to add supplemental fertilizer later in the season.
What advantages does the Houseplant Potting Mix with perlite offer over other indoor mixes?
The Houseplant mix combines perlite, sphagnum, and peat moss to create a lightweight, well‑draining medium that reduces the risk of fungus gnats. It’s certified by the Mulch & Soil Council, providing an extra layer of quality assurance. This blend is especially suitable for delicate foliage plants that prefer airy soil conditions.
How important is the “feeds plants for up to 6 months” claim when comparing value?
A six‑month feeding period means you get continuous nutrient release without needing immediate supplemental fertilizer, which can save time and money. Products lacking this claim, like the Organic Outdoor mix, may require additional feeding after two months, potentially increasing overall cost. Evaluate how often you plan to fertilize to determine which product offers the best value for your gardening routine.