Indoor plants are sweeping the nation.
Industry figures show that around 50 million were sold last year, which works out to be roughly two indoor plants per Australian.
Craig Miller-Randle owns plenty more than two plants.
A furniture designer by trade, Craig's true calling is tending to the hundreds of indoor plants he's lined his inner-city Melbourne home with.
"I'm a self-confessed plantaholic," he says.
"With more people renting or downsizing, having a big sprawling backyard isn't the only way to enjoy plants and gardening."
Craig's plants are always at their stunning best, which has won him tens of thousands of followers on Instagram. It's even earned him a spot as Gardening Australia's new guest presenter.
Read on for his tips on giving your indoor plants a good grounding.
Craig knows that like any garden, it all starts with the soil. Or in this case, the potting mix.
"Potting mix is different to soil. It provides more drainage and aeration. Roots need air to survive," he says.
"If it doesn't drain really well it gets waterlogged — the water replaces the air in the mix. If it's airless the roots rot and die from fungus and bacteria … you want big gaps in the media for the air to get in."
Craig's magic bullet for getting a good mix (and healthier plants) is perlite. It's a product made from expanded volcanic glass, and you can easily find it at nurseries and hardware stores.
While not suitable as a growing media on its own, it is ideal for adding into your own potting mixes to improve their performance.
"It keeps it friable and moderates moisture," explains Craig.
"I put it in everything, it's like my salt … It provides everything: oxygen and water. It's the perfect environment for roots."
Making your own potting mix is an easy and cheap thing to do, and Craig says it will really take your indoor plant game to the next level. He has two types you can make at home:
This is simple standard potting mix with around 20 per cent perlite mixed in.
Craig uses this for "the biggest range of plants" including prayer plants and peace lilies.
If it's in budget, buy a potting mix with the Australian standard "premium label" on the bag, as this will drain more freely, and it's often only a few extra dollars.
Craig makes a special blend for his "epiphytic" plants that prefer to grow up poles and totems.
Think plants like monstera, philodendrons and devils ivy. They're some of the most stunning in Craig's collection, and he credits his special mix.
"They're growing either on a mat of leaf litter on a forest floor or directly on and up a tree. They need larger particles in their mix as a result."
Orchid mix is readily available at nurseries and hardware stories. It's made out of larger chunks that these plants will love to wrap their grasping roots around. Craig says the charcoal helps to absorb impurities that may accumulate over time.
These two custom potting mixes can be combined by hand and stored for when you need to repot your plants.
Craig's overall advice is to "keep it simple". A more complicated potting mix won't guarantee greater success.
"It makes no difference in my experience. You've got enough to worry about. You've got limited space, you can't be mixing all these components from 10 different bags, it's a hassle," he says.
Patrick Honan is a researcher for Gardening Australia.
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