Specifications : As with any garden, soil preparation is what really counts when it comes to being successful in growing in containers. It’s the foundation. Pick your life-giving metaphor and you get the idea. In other words, select the right potting mix recipe for your plants and they will thrive. Skimp on the soil and you’ll get weak, non-productive plants that require more work to maintain and are susceptible to all kinds of pest problems.

Potting soil isn’t the same as fertilizer, which acts more like a vitamin to your plants. It also isn’t always the same as a potting mix. Although the two are “functionally pretty much the same,” potting soil — as its name suggests — sometimes has actual dirt in it, whereas a mix never does, according to blogger Erinn Witz of Seeds and Spades. Still, even with that very technical point, the two terms are usually used interchangeably or branded as “soil mix”

So what does potting soil do? Potting soil should have the right ingredients to oxygenate and provide nutrients for plants. which is why estate gardener and horticulturist Brooke Medlin says potting mixes are typically composed of peat, a little bit of shredded pine bark, and superheated minerals like perlite or vermiculite to aerate the soil. “Peat and perlite are really made for aeration, so they’re found in pretty much every potting mix you’re going to find,” she says. The ingredients in potting soil are also meant to “improve drainage, encourage moisture retention, resist compaction,” Witz explains. The latter means the soil becomes dense, making it hard for a plant to absorb water.

A general potting soil mix will suit a variety of houseplants, though something more prickly like a succulent might require a more specific mix catered to its needs. Medlin recommends finding a potting mix that’s specific to your plant, noting that most nurseries and big-box stores will have them for palms, citrus, and more.