Here. Take it. I’ll immediately spare you the “I get asked this all time” shtick and dispel the idea I’m going to give you some magic formula to grow giant plants immediately. This note is just an attempt to spur some introspection and analysis when it comes to what substance your using to grow tropical plants; and, of course give some solid product recommendations.

I grow exotic plants indoors here in North Carolina and this has lead me to experiment with many potting mixes over the years. This note will highlight what has worked, what hasn’t worked, and provide my exact recipe with links.

First do research: It is vital that a collector determines what conditions a plant requires to thrive; there is no “one size fits all” potting medium. Do not be convinced by anyone on the internet that there is some miracle substrate guaranteed to make your Anthuriums thrive.

Then let’s talk about conditions and expectations. Where your grow your plants and how often you will be watering are components to consider. It is important that both you and your plant have your needs met. Be honest with yourself about frequency of watering and your setup. Everyone will tell you what ratios of amendments to add, but what I’m hoping to also convey here is that you have to customize your substrate to align with your actual situation.

Don’t BS yourself or think you have to do what the internet says: If you know you can’t water but once a week then to hell with everyone saying you need a free draining mix. Either grow less thirsty plants; or try a denser mix and see what happens. Experimentation, patience, and self analysis are key traits one should hone.

The exact components, ratios, etc. are only part of the equation. The most free draining mix in the world will still rot your new Anthurium if you leave the pot sitting in a puddle for two weeks.

I grow all my plants indoors here in North Carolina inside AC Infinity grow tents. The plants here receive 18hr of full spectrum LED grow light per day ranging from 150-450fc (this just means rather dark for most plants). Plants are watered with reverse osmosis filtered water 3 times per week. I have inline exhaust fans and oscillating clip fans circulating air on interval timers. Temperatures range from 65-80ºF.

These plants are the subject of my professional life as well as my favorite hobby, so I’m going to be able to be around my plants a lot. Being able to water a lot means I can handle a somewhat free draining mix. I also have a coworker at my studio that is able to assist with this. I say this to give context to the fact that my potting mix has to be able to withstand 3 good waterings per week for every plant.

I expect my mix to be pH balanced for maximum nutrient uptake and root health. I also expect a long lasting mix-this pertains more to mature plants finding their “forever pot” but even if you plant to repot once a year or more it is still best to use a mix with durable components. I expect a mix that balances mine and my plant’s needs for water.

Exceptions to the rules.

Before I list the ingredients I just want to say that this mix is not new and is used (in some form) by many botanical gardens, plant collectors, and can be found premade by many online plant boutiques. I first decided to make a custom Aroid mix back in 2018 as my collection was starting to grow and things (that I wasn’t killing) needed new pots. I knew that I knew very little and there was even less info out here to be consumed on the internet at that time; so I consulted notable collector of the esoteric: Jay Vannini. Mr. Vannini gave me his version of what is known as the ABG mix (named after the botanical garden in Atlanta that made it popular). His mix was 4 parts orchid bark, 1 part NZ tree fern fiber, 1 part medium horticultural charcoal, 1 part pumice; add in nutricote, gypsum, and dolomitic lime for long-terms nutrients.

In my left hand you can see one of Mr. Vannini’s round net pots and in the other one of the rands aircone pots I use. The net pots allow much more air flow to the roots, but also allowed my plants to dry out far too quickly.

This mix worked fine for me but over the years I stared noticing that certain things were never really happy and stayed dry. After some investigation I realized that it was the fact that Mr. Vannini’s recipe was based on his conditions and methods that was not translating to my setup.

I determined that it was a combination of factors that was causing me issues at the time:

1- Mr. Vannini grows in 50 ft greenhouses in the Bay Area Cali. I grow in grow tents indoors in N.C.

2- Mr. Vannini has overhead sprinklers that water as much as he wants. I water 3 x week with a backpack sprayer. Think hours per day vs 3 x per week.

3- Mr. V loves growing in net pots which allows maximum draining. I grow in plastic (Rand’s aircone) pots.

SO I CHANGED MY MIX!

When all of these factors in mind I concluded that it was best, even though I consider Mr. V to be the expert of experts, to switch it up. You have to grow based on your experience and I knew that I was not going to be able to water as frequently as Mr. Vannini, thus I needed a mix/pot combo that retained more moisture.

Here you can see the medium size orchid bark. This conifer bark is the essential and long lasting backbone of the mix. I don’t suggest going with other brands on this, the Orchiata brand delivers uniform size and and a clean product (not an ad just a fact that I can attest to as someone that has been burned).

Cultural factors:

It is also vital to consider where the plant [or parent(s)of the plant] originate, how the grow, and how this translates to your scenario. A cloud forest epiphyte is going to have different needs than a riparian lowlander.

My current mix.

This is a base mix that I use for about 70% of what were grow here. Again I want to stress again that research and evaluation is key to determine what works best for you and your plants.

Arthur’s mix:

1 part Orchiata orchid bark small

1 part Orchiata orchid bark medium

2 parts NZ tree fern fiber

1 part horticultural charcoal

1 part pumice

nutricote, encapsulated gypsum, and dolomitic lime are added as directed (1/2 tsp per gallon of mix for the lime and encap and use nutricote as directed)

Good size pumice like this will provide excellent air flow to the roots of your Anthuriums.

Honorable mentions:

Mineral based substrates like Lechuza’s pon have given me mixed results when coupled with their self watering pots. It has worked great with regular nursery pots with drainage holes, especially for Mexican Aroids from the Chiapas Highlands and lithophytes. Many growers are having excellent results with the self watering pots + mineral based substrate. Again this has been a mixed bag in my experiments. I do think this system would work well for those that want to water less but be cautioned that some species may not love the transition.

Cache pots/reservoirs are much the same as Lechuza for me.. mixed results.

Root pouches and root bags have worked exceptionally well for me over the years and are something I’ll be reintroducing more in the near future.

Chopped sphagnum works great for thirsty juvenile plants that will be repotted within in a year.