Comparison: Best Potting Soil For All Plants (Updated | Nov 11th)

Look for a blend that balances water retention with good drainage, includes a light texture like perlite or coir, and contains a slow‑release fertilizer to feed plants for several months. A mix that reduces fungus gnats, such as those without compost or bark, can also keep indoor plants healthier. Finally, consider whether you prefer an organic formula or a conventional one with added nutrients.

The Houseplant Mix combines perlite, sphagnum peat moss, and peat to create a lightweight medium that is less prone to gnats, while the Indoor Mix relies on coconut coir for water‑holding capacity and also limits gnats by avoiding compost. Both feed plants for up to six months, but the Indoor Mix is packaged in larger 16‑qt bags and is marketed for a broader range of indoor foliage, including climbing and tropical varieties. The Houseplant Mix comes in a 4‑qt bag, making it a good choice for smaller containers.

Miracle‑Gro Moisture Control Potting Mix uses an exclusive AquaCoir formula that absorbs up to 33 % more water than standard mixes and includes a wetting agent to prevent both over‑ and under‑watering. It also feeds plants for up to six months, helping maintain consistent growth. The mix is sold as a two‑bag bundle (8 qt each), which is convenient for larger garden projects.

Both Back to the Roots and Wonder Soil provide 100 % organic, peat‑free blends that include natural amendments such as worm castings, mycorrhizae, and kelp, which can improve root development and overall plant vigor. Back to the Roots emphasizes a lighter carbon footprint and a satisfaction guarantee, while Wonder Soil expands fourfold when hydrated, offering space‑saving storage. If you prioritize sustainability and organic inputs, the added price can be justified by the long‑term health benefits.

Most Miracle‑Gro blends (Houseplant, Indoor, Moisture Control, and standard Potting Mix) promise up to six months of feeding, delivering twice the growth of unfed plants. The organic Outdoor Mix feeds for about two months, while the Organic Indoor Mix also provides six months of nutrition but relies on a natural fertilizer blend. Back to the Roots and Wonder Soil contain slow‑release organic amendments that feed continuously but without a specific month‑count claim.

A 12‑inch container typically requires roughly 1 qt of soil, so a 4‑qt bag (like the Houseplant Mix) will fill one pot with some extra for top‑dressing. For larger projects, the 16‑qt bags found in the Indoor Mix, Organic Indoor Mix, or Back to the Roots provide enough for about 12‑15 such pots. If you plan to grow multiple plants or larger varieties, consider the two‑bag bundles of Moisture Control (8 qt each) for better value.

Bundle packs, such as the two‑bag 8‑qt Moisture Control or the two‑bag 16‑qt Indoor Mix, lower the cost per quart and include enough soil for several containers, making them more economical for larger gardens. Single‑bag options like the 4‑qt Houseplant Mix are convenient for beginners or small‑scale projects but have a higher per‑quart price. Evaluate how many pots you need and whether the added volume justifies the upfront cost.