Plant notes

Why I Started Mixing My Own Potting Soil (And My First Disasters)

After killing my third pothos with root rot and spending £6 on another bag of 'premium' compost that turned into a brick within weeks, I decided to try mixing my own potting soil. It's been six months of trial and error, and honestly, I wish I'd started sooner. Here's what I've learned in my tiny kitchen with bags of perlite taking over the hallway.

The Breaking Point: Why Bagged Soil Wasn't Working

I used to grab whatever potting mix was on offer at the garden centre, and it was a disaster. The cheap stuff would compact into cement after a few waterings, leaving my plants either drowning or bone dry with no in-between. The expensive stuff was better but still too heavy for my aroids and succulents. I lost a beautiful monstera to root rot because the soil just held too much moisture. That plant cost me £25, and I'd had it for two years. I was tired of guessing whether the soil was the problem or my watering schedule, so I decided to take control of what actually goes in the pots.

My Basic Mix (That Actually Works)

After reading too many conflicting forum posts, I settled on a simple recipe that I adjust depending on the plant: 40% regular multipurpose compost, 30% perlite, 20% orchid bark, and 10% horticultural grit. I mix it in an old washing-up bowl on my balcony because doing it indoors once left perlite dust everywhere for weeks. For my succulents, I flip it to 50% grit and only 20% compost. For my calatheas who like it moist, I add some coir. The first batch I made was way too bark-heavy and water just ran straight through, so my fiddle leaf got crispy. Now I actually measure with an old takeaway container rather than eyeballing it.

The Mess, The Storage, The Reality

Let me be honest: mixing soil is messy and my partner hates it. I keep the ingredients in old compost bags rolled down tight, stacked in the cupboard under the stairs. The perlite gets everywhere no matter how careful I am, and I've learned to wear my gardening clothes and do it outside when possible. I thought I'd save money, but the upfront cost of buying all the ingredients separately was about £40. However, that's given me enough mix for dozens of repottings over six months, whereas I'd have spent that on four or five bags of pre-mix by now. I also keep a small sealed container of ready-mixed soil so I'm not mixing a huge batch when I just need to top up one pot.

What I'd Do Differently (And Still Get Wrong)

I initially didn't sift my bark, and some chunks were absolutely massive, which left awkward air pockets around roots. Now I pick through it and remove anything bigger than my thumbnail. I also made the mistake of pre-mixing a huge batch and storing it, but it got a bit funky and possibly grew mould, so now I mix what I need per session. I'm still figuring out ratios for specific plants—my ferns seem to want something different every season, and I definitely made my pothos mix too gritty last month because it's drying out too fast now. But even with mistakes, I feel more in control, and my plants do genuinely seem happier with better drainage than they ever were in straight bagged compost.

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