Comparison: Best Target Miracle Grow Potting Soil (Updated | Nov 11th)

Indoor mixes, such as the Miracle‑Gro Houseplant and Indoor Potting Mixes, contain a blend of peat, perlite and coconut coir that retains moisture without encouraging fungus gnats, which is ideal for houseplants. Outdoor mixes are formulated with a higher proportion of peat and natural fertilizers to support vigorous root growth in larger containers exposed to the elements. Choose the indoor version for foliage, tropical or low‑light plants, and the outdoor version for garden vegetables, herbs and seasonal flower beds.

Moisture Control uses an AquaCoir formula that can absorb up to 33% more water than standard mixes, reducing the risk of both over‑ and under‑watering. It also includes a built‑in moisture‑regulating agent that releases water slowly, which is helpful for busy gardeners who may miss watering schedules. The feed lasts up to six months, so plant growth remains consistent without frequent fertilization.

The Organic Indoor Mix combines responsibly sourced sphagnum peat, coir and a quick‑release natural fertilizer, providing a more sustainable option with fewer synthetic chemicals. It also includes a built‑in water‑balance system that protects against both over‑ and under‑watering, similar to the Moisture Control line. If you prefer an eco‑friendly product and are willing to pay a modest premium, the organic mix offers comparable plant performance with added environmental benefits.

The Cactus, Palm & Citrus Potting Mix features a fast‑draining formula enriched with Miracle‑Gro Plant Food, which prevents water‑logging while supplying nutrients for succulent‑type roots. Its coarse texture mimics the gritty soils these plants thrive in, reducing the chance of root rot. For both indoor and outdoor use, this mix is the most suitable choice for cacti, palms and citrus trees.

The combination of perlite, sphagnum moss and peat creates a well‑aerated medium that dries out quickly on the surface, making it less attractive to fungus gnats that prefer moist, organic matter. Perlite also improves drainage, further discouraging gnat breeding. This mix is marketed as “less prone to gnats,” which is especially useful for delicate foliage plants.

A 4‑quart bag of the Houseplant Potting Mix fills an 8‑inch pot, while an 8‑quart bag of the standard or Moisture Control mixes covers two 8‑inch containers. For larger 12‑inch pots, a 16‑quart bag of the Indoor or Organic Outdoor mixes is appropriate, and a 25‑quart bag of the Organic Outdoor mix can fill three 10‑inch containers. Match the bag volume to the number and size of pots you plan to fill to avoid waste.

Most Miracle‑Gro mixes, including the standard, Indoor, Moisture Control and Cactus blends, provide nutrients for up to six months, promoting steady growth and bloom production. The Organic Outdoor mixes contain a quick‑release natural fertilizer that lasts about two months, after which a supplemental feed may be needed for continued vigor. Seed Starting Mixes are designed for rapid root development and typically require additional feeding after seedlings emerge.

For flowering plants, the standard Miracle‑Gro Potting Mix and the Moisture Control mix both claim to boost bloom color and size by delivering consistent nutrients for up to six months. Foliage‑focused plants benefit from the Houseplant Potting Mix or Indoor Mix, which emphasize balanced nutrient levels and reduced gnat risk, supporting lush leaf growth. Selecting a mix that aligns with your primary plant goal—flowers or foliage—will enhance overall performance.