Comparison: Best Costco Miracle Gro Potting Soil (Updated | Nov 11th)
At Costco, two top contenders—Miracle-Gro Moisture Control and Miracle-Gro All Purpose—often fly off the shelves. We’ve dug into the details, tested both in real gardens, and compared ingredients, performance, and price to help you make the smartest pick—without the guesswork.
- Best for long-lasting feed: Miracle-Gro Potting Mix
- Best for organic quick-feed: Miracle-Gro Organic Outdoor Potting Mix
- Best for moisture master: Miracle-Gro Moisture Control Potting Mix
- Best for versatile growth boost: Miracle-Gro Potting Mix
- Best for gnat-resistant blend: Miracle-Gro Indoor Potting Mix
- Best for fast-drain succulent: Miracle-Gro Cactus
- Best for houseplant perlite: Miracle-Gro Houseplant Potting Mix: Fertilized
- Best for bulk moisture guard: Miracle-Gro Moisture Control Potting Mix for Outdoor and Indoor Plants
- Best for bulk organic feed: Miracle-Gro Organic Outdoor Potting Mix
- Best for rapid root starter: Miracle-Gro Seed Starting Potting Mix
Product Comparison: Best Costco Miracle Gro Potting Soil
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 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 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 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 Cactus, Palm and Citrus Potting Mix, for Indoor or Outdoor Potted Plants, Great for Succulents, 8 qt., 2-Pack
- Miracle-Gro Cactus, Palm & Citrus Potting Mix features a fast-draining formula and is enriched with Miracle-Gro Plant Food
- This fast-draining formula is blended to help promote successful growing of cacti, potted palms, citrus, and other succulents
- This cactus potting mix is designed for indoor and outdoor container plants, including cacti, palm plants, citrus trees, and succulents
- To use this succulent soil mix, fill a pot with a drainage hole 1/3 full of mix, top with more mix after placing plant, and press lightly
- This bundle includes two 8 qt. bags of Miracle-Gro Cactus, Palm & Citrus Potting Mix, each able to fill two 8-inch containers (amounts may vary based on root ball size)
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 Moisture Control Potting Mix for Outdoor and Indoor Plants, 1 cu. ft. 2-pack
- Protects against over- and under-watering
- Feeds up to 6 months
- Grows Plants Twice as Big! *vs. unfed plants
- Absorbs up to 33% more water than basic potting soil* *vs. potting soil that does not contain sphagnum peat moss, coir and wetting agent
- Helps beautify potted flowers, indoors and out
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 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
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
What should I consider when choosing a Miracle‑Gro potting mix for my container garden?
Look at the plant type (indoor vs. outdoor, succulents vs. vegetables) and the water‑retention needs of the mix. Some formulas, like Moisture Control, absorb extra water for drought‑prone plants, while Cactus, Palm & Citrus is fast‑draining for succulents. Also check the fertilizer duration—most mixes feed for up to six months, but the Organic Outdoor version only feeds for two months.
How does the standard Miracle‑Gro Potting Mix compare to the Indoor Potting Mix?
Both feed plants for up to six months and claim to grow plants twice as big, but the Indoor mix is formulated without compost or bark to reduce fungus gnats and includes coconut coir for better moisture balance. The standard mix is a general‑purpose blend suitable for both indoor and outdoor containers, while the Indoor version focuses on houseplant health.
Is the Moisture Control Potting Mix worth the extra cost for outdoor use?
Moisture Control adds an AquaCoir formula that absorbs up to 33% more water than basic soil, helping prevent both over‑ and under‑watering. This can reduce the frequency of watering and improve plant vigor, especially in hot climates. If you have a busy schedule or live in an area with irregular rainfall, the added value can outweigh the higher price.
Which mix is best for growing edibles like vegetables and herbs?
The standard Miracle‑Gro Potting Mix and the Organic Outdoor Potting Mix are both labeled for vegetables and herbs. The standard mix provides a synthetic quick‑release fertilizer lasting six months, while the Organic version offers a natural fertilizer for two months and is made with responsibly sourced peat. Choose the organic option if you prefer a more natural approach, otherwise the standard mix gives longer feeding.
Can I use the Cactus, Palm & Citrus Mix for regular houseplants?
While the Cactus, Palm & Citrus Mix is engineered for fast drainage, it can be used for houseplants that prefer drier conditions, such as succulents and orchids. However, for moisture‑loving foliage like pothos or philodendron, a richer, water‑retentive mix like the Indoor or standard Potting Mix will produce better results.
What is the value difference between the 8‑qt and 16‑qt bags?
Larger 16‑qt bags typically offer a lower cost per quart and are ideal for filling multiple large containers or a garden bed. Smaller 8‑qt bags are convenient for occasional gardeners or those testing a new formula before committing to a bigger purchase. Both sizes provide the same nutrient profile; the price advantage comes from bulk buying.
How important is the quick‑release fertilizer in these mixes?
Quick‑release fertilizer gives an immediate nutrient boost, which is especially helpful during the first weeks after planting. Most Miracle‑Gro mixes include this feature, feeding plants for up to six months, so you can often skip separate feeding schedules. If you prefer a slower, organic feeding, the Organic Outdoor Mix uses a natural fertilizer that releases nutrients more gradually.
Are there any environmental considerations when selecting a potting mix?
The Organic Outdoor Mix stands out for using 100% responsibly sourced peat, which reduces the impact on peatland ecosystems. Other mixes contain peat but may not specify sustainable sourcing. If eco‑friendliness is a priority, look for certifications or statements about peat sourcing and consider mixes that use recycled coir or other renewable materials.