First up – What’s ‘soil drainage’?
It’s a bit of a buzzword in the horticulture and plant parent communities, and mentioned on the reg in our app care guides. So what does soil drainage actually mean?
Soil drainage describes how well water travels through your soil. You may have heard the term well draining soil before, which is basically just soil which has good drainage.
It sounds like we’re referring to a certain type of soil, but we’re not. It’s not about the type of soil but what’s in the soil you’re using.
What’s the big deal about drainage, anyway?
Easy. Good drainage ensures the soil is properly aerated to keep your plant – and its roots – healthy. When soil becomes clogged, your plant’s roots are deprived of oxygen, leading them to suffocate and die over time. Excess water from improper drainage can also cause fungal or bacterial growth which is something neither you or your plant want!
How do we solve this? Adding some good stuff to your standard potting mix.
Standard potting mix 101
Standard Potting Mix is likely the OG soil that came with your plant when you locked eyes and fell in love at the Bunnings nursery. This mix works great for commercial growers with optimal lighting and watering routines but may not be the best at home with you long term.
Your plants won’t get as much sunlight in your space as it would in a production greenhouse nor are you likely able to water meticulously as growers do. Both factors affect how standard potting mix performs for your plant. If the mix dries out completely, it can become hydrophobic, meaning the particles in the soil will repel water instead of soaking it all in. On the flipside (because there’s usually always a flipside), standard potting mix can hold onto a lot of moisture due to its density. If you overlove your plant by watering too often, it will take a while to drain and lead to symptoms of overwatering.
Add to your Standard Potting Mix for optimal drainage
There’s a simple solution to levelling up your SPM (that’s standard potting mix, btw): add some good stuff in the mix.
Perlite
The most common addition and my top recommendation is adding perlite. Made from volcanic glass and heated to extreme temps, it’s a lightweight, styrofoam-like granular material that has neutral acidity and a porous structure. All you need to do is mix it in to your current soil mix.
Where perlite sits in your soil becomes empty space, allowing for water to flow through the soil much more smoothly. That’s some A+ aeration and soil drainage.
Hot tip: When perlite shopping, try to find a mix with larger, more rigid pieces. Finer perlite can break down easily and risks becoming dense, like sand.
Orchid Bark or Coconut Coir Chips
Although they don’t sound like much, orchid bark and/or coconut coir chips can be a lifesaver for your houseplants. These coarse, chunky bits of bark provide an added layer of drainage, which your plants love. Just like perlite, mix them into your soil mix to let your plant’s roots breathe without sacrificing perfect soil moisture. For the perfect ratio I'd recommend 2 parts SPM, 1 part Perlite and 1 part bark or chips.
Hot tip: As the name suggests, orchid shops are normally a great place to get bulk bark for a bargain.
Remember: Good soil drainage is one of the most important things when it comes to keeping your houseplants happy and healthy. Adding perlite and bark chips to your standard potting mix will keep you out of deep water (literally) when it comes to symptoms of overwatering and help your houseplant live the good, long life it deserves.