What to grow your orchid in
There are an incredible range of things you can grow orchids in. We’ll cover the more common options here but, as one of our orchid mentors used to say, ‘a good grower can keep an orchid alive in cigar butts and sherbert’ (not recommended for us mere mortals, though). Some orchid growers use elaborate recipes for each type of plant - one friend said he had 21 ‘ingredients’ in his ladyslipper mix!
This is rarely necessary though, unless you get into really specialized and rare types. Generally, plan to repot your orchid every two years or so and, ideally, just after it has finished flowering. For all types of media keep in mind that the part which normally retains the most moisture is just below the plant, and it is really important to remove as much old media from this area as you can, when repotting, since it will be the most degraded. To that end, please don’t reuse old media - it has normally started turning itself into compost and will keep way more water than you want around the roots. It can also harbor sizeable populations of fungi, bacteria, insect eggs, etc. which, combined with its retained moisture, gives your orchid an uphill battle as it settles in.
A note on using pots
You can, however, reuse pots if you clean them well and disinfect them between orchid inhabitants - a soak in a mild bleach solution followed by a good rinsing and then letting them dry out is an easy and inexpensive way to disinfect pots before reuse. We grow almost all of our orchids in plastic pots, but you’ll occasionally come across ones in clay or concrete pots, or mounted (we go into detail on mounting in a separate article). Plastic pots don’t let water evaporate through them, and so tend to keep the plants more moist. This includes our eco-pots, which are made of mostly rice hulls and polymers. Clay and concrete pots can let water through, both to take it up and to let it out - leading to drying. Some of the water which gets into the pores of clay or concrete pots will also, inevitably, carry in minerals and salts which build up over time and sometimes show up as hard white deposits like you see in your shower or sink. These block the ability of the pot to let water through, and can also sort of burn the roots which come in contact with them through their high salt concentrations.
Consider retiring pots which have a decent amount of this build-up. However, retired clay pots can be smashed to provide filler at the bottom of plastic pots for decreasing trapped moisture, much as styrofoam is used for (more details on this below). And smashing the pots is often therapeutic when dealing with a tough day or a plant which refuses to flower. If you’re feeling less violent, these pots often make good ‘sleeves’ for slipping plants in plastic pots into, which can provide a solid base for top-heavy plants prone to tipping over.
If you prefer to mount your orchids, take a look at our article on mounting orchids!
Bark
A good all-purpose medium. For orchids which don’t like staying moist (like Vandas or Angraecoids), large chunks are best. For orchids which like it really moist (like slippers), small chunks are best. Medium chunks are the most common, and good for the majority of orchids. You can also mix bark with other types of media to decrease or increase the amount of retained moisture. Some folks swear by soaking bark beforehand, others insist on using it dry - we split the difference and recommend rinsing it briefly, to remove dust and debris, shortly before repotting. Our Dry Mix potting media includes bark.
Sphagnum Moss
Very common for orchids you buy from supermarkets, and for baby orchids - where drying out might lead to death. This medium holds a lot of water and, if not monitored, can lead to rot. That being said, this is a good option for growing orchids which like it a little more moist or for folks who can forget to water their orchids for weeks at a time (no judgment here!). It’s sold dry and then needs to be rehydrated by soaking in water. After soaking it is critically important to squeeze out as much water as you can and then fluff it up - please, for the love of all that’s holy, don’t put your orchid in dripping-wet sphagnum! For orchids growing in sphagnum it is particularly important to check the moisture before you water it; if you look below the top layer it should be just barely moist by appearance or touch, to the point where you’re second-guessing yourself about whether it’s moist or if you’re just imagining it. If the sphagnum looks moist, hold off a little longer before watering. Our Wet Mix potting media includes sphagnum moss.
Lava Rock / Cinder
This medium doesn’t break down, but the many pores can hold a little bit of water (although way less than plant-based media like bark or sphagnum). It’s often mixed in to provide more air/drainage space when potting in bark. You can grow a plant which likes just a little moisture in pure cinder, but since it doesn’t break down into nutrients you’ll need to fertilize it a little more. There are also some trace minerals, which might be uptaken by the roots. The edges of cinder are often rather sharp, and can scratch you up a little bit while repotting - consider using gloves and/or protective nail polish to protect your hands and fingernails, especially if you don’t have a lot of callus. Our Dry Mix potting media includes cinder.
Perlite
Another media which doesn’t break down, and with fewer pores than cinder so it tends to retain less water.. This is a common addition for ‘lightening’ media, to increase air and water flow. It’s also generally cheaper than most of the media covered here, but rarely used as the sole ‘ingredient’ in potting mixes. Handling perlite often creates small clouds of white powder, which is easy to inhale and then leave you coughing or sneezing it out for the next few minutes (or hours). We strongly recommend either wearing a mask when handling it, or wetting it down before, and as, you work with it.
Styrofoam / Packing Peanuts
Many a new grower has been surprised, when repotting an orchid, to find styrofoam packing peanuts in the very bottom of the pot! These are provided to create a little space at the bottom of a pot, to prevent the media/roots there from staying wet from the pooled water when pressed up against the plastic. Even orchid experts sometimes use these for species which need really good drainage. They can be reused if you clean and sanitize them, or you can rinse off others you have lying around and put them into the potting before adding the plant or media. Please only use styrofoam packing peanuts for this; we encourage you to use the eco-friendly peanuts for shipping things, but in the bottom of a pot they break down into a mush which is a perfect breeding ground for diseases.
If you don’t have clean styrofoam lying around, and don’t want to buy something which can outlive you and be a blight on the landscape, there are a range of other things you can use to provide this space at the bottom of the pot. Shards of old clay pots are a very common substitute, when cleaned off, and can wick some of the water away. Cinder also works well, or even the ‘blue stone’ used for driveways. Clay shards, cinder, and stones can also help anchor a pot which is in danger of tipping over. Beyond these the sky's the limit, but try to stick with things which are inert and inorganic.
Potting Soil
Please, please, please don’t subject your poor orchid to potting soil. There are a small handful of orchids which tolerate potting soil, but most get waterlogged and die. If you have an orchid in potting soil, it's not too late! Check out our article on repotting orchids.