Indoor potting soil is a light, well-draining growing mix made for plants in containers. Unlike garden soil, it stays loose in a pot, so water drains through and air reaches the roots. Most mixes combine peat or coir with perlite or similar material, and some add bark or nutrients. Use it for houseplants in containers that drain, and match the mix to the plant.

The best soil for most houseplants is a general indoor potting mix that drains freely but still holds some moisture. Succulents and cacti do better in a grittier cactus mix, and aroids such as monstera like a chunkier blend with added bark. Avoid garden soil, and avoid reusing soil from a plant that died, since it can carry pests and disease.

Cactus soil and succulent soil are essentially the same thing: a gritty, fast-draining mix for plants that store water and rot in wet soil. Labels vary by brand, so look for a mix that feels loose and sandy rather than dense and peaty. Either works for cacti and most succulents in a pot with a drainage hole, and adding perlite makes a general mix closer to both.

Perlite is a lightweight volcanic glass expanded into white, porous pebbles. In potting soil it improves drainage and aeration, so water moves through and roots get air, and it keeps a mix from compacting over time. Perlite is inert, so it adds no nutrition, and it is widely used in houseplant, succulent and propagation mixes.

LECA stands for lightweight expanded clay aggregate: small, round, porous clay pebbles, also sold as LECA balls or clay pebbles. They are used in semi-hydro growing, where the plant sits in pebbles over a water reservoir, and as a drainage layer or a mix amendment. The pebbles hold water in their pores and release it slowly.

Orchid bark is chunky chipped tree bark used to grow orchids and other plants whose roots want air, such as many epiphytes and aroids. It creates large gaps that let water drain and roots breathe, and it breaks down slowly over time. It is used on its own for orchids or mixed into potting soil to make a chunkier, faster-draining blend.

Perlite and vermiculite both lighten a soil mix, but they behave like opposites: perlite is dry and airy and drains fast, while vermiculite is soft, holds water and nutrients and keeps a mix moist. Pick perlite for cacti, succulents and anything that hates wet feet, and vermiculite for seed starting and thirsty plants. Chive stocks perlite; the plants are free to have opinions about the rest.

Chive sells perlite from its Toronto studio and plant shop at 702 Queen Street West, priced in CAD. Ships across Canada from our Toronto studio. Pick-up is available at the shop for orders placed before 3 pm, and the same collection carries cactus soil, LECA clay pebbles and orchid bark when they are in stock.