Soil & potting mix
Best soil for Pak Choi (Brassica rapa subsp. chinensis)
Also called Bok choy, Chinese cabbage, Pak choy.
More about pak choi
About Pak Choi
Brassica rapa subsp. chinensis · also called Bok choy, Chinese cabbage · edible
Pak choi is a fast, succulent Asian brassica grown for its crisp white or green leaf stalks and tender dark leaves in a loose, non-heading rosette. It crops in as little as 4-8 weeks and is ideal for stir-fries. Quick and easy, it suits spring and late-summer sowings; hot, dry conditions and long days readily trigger bolting, so cool, moist growing is key.
Preferred mix: Fertile, moisture-retentive loam, pH 6.0-7.5
Watch for — Flea beetles: Beetles pepper the tender leaves with small holes, worst on seedlings in dry weather. Cover with fine mesh, keep soil moist, and sow into warm conditions for fast growth.
Why pak choi needs this mix
Pak Choi hates drying out, so it wants a mix that stays evenly moist — but it still needs perlite so "moist" never tips into "waterlogged".
- Pak Choi comes from damp, shaded forest floors and has fine roots that scorch and brown the moment the rootball dries — the mix has to hold a steady reserve.
- Coir and compost give that reserve, while perlite keeps enough air that the constantly-moist mix does not turn anaerobic.
- Even moisture also keeps its thin leaves from crisping at the edges, which is this plant’s most visible stress signal.
For the full picture on what makes up a good mix, see our guide to the main types of soil and potting media — it explains why each ingredient above behaves the way it does.
What goes wrong with the wrong mix
The wrong soil is one of the most common reasons pak choi struggles, and the damage often shows up weeks later as a watering problem. For this species specifically:
- A free-draining, gritty mix dries too fast for pak choi — you get crispy brown edges and frond or leaf drop within days of one missed watering.
- A pure, airless peat mix swings the other way: it holds water but suffocates the fine roots and rots the crown.
- Letting the mix dry to the point it shrinks from the pot is very hard to re-wet evenly and stresses the plant badly.
Using a sharp, fast-draining "houseplant" or cactus-leaning mix that lets pak choi dry out. It needs a moisture-retentive but still airy blend.
pH — does it matter for pak choi?
Pak Choi prefers a slightly acidic mix (around pH 5.5-6.5); a peat-free compost-and-coir blend sits there naturally, so routine pH testing is unnecessary.
If you want to check or adjust it, the soil pH guide walks through testing and the safe ways to nudge a mix more acidic or more alkaline.
DIY mix vs a bagged one
A good peat-free houseplant compost works for pak choi straight from the bag if you mix in some perlite for air. The DIY ratio above gives a more reliable moisture-to-air balance.
Drainage and the pot
Use a pot with a drainage hole but a less-porous material (plastic or glazed) so it does not dry too fast. Bottom-watering keeps the mix evenly moist without sogging the crown.
Peat-free mixes slump and compact as they hold moisture, so refresh pak choi's mix every 12-18 months to keep air in the rootball even if the pot size is unchanged. When the time comes, our repotting guide for pak choi covers the timing and technique step by step.
Pak Choi soil — frequently asked questions
What is the best soil mix for pak choi?
3 parts peat-free houseplant compost : 1 part coco coir : 1 part perlite. Pak Choi comes from damp, shaded forest floors and has fine roots that scorch and brown the moment the rootball dries — the mix has to hold a steady reserve.
Can I use normal potting soil for pak choi?
A free-draining, gritty mix dries too fast for pak choi — you get crispy brown edges and frond or leaf drop within days of one missed watering. A good peat-free houseplant compost works for pak choi straight from the bag if you mix in some perlite for air. The DIY ratio above gives a more reliable moisture-to-air balance.
Does pak choi need a special pH?
Pak Choi prefers a slightly acidic mix (around pH 5.5-6.5); a peat-free compost-and-coir blend sits there naturally, so routine pH testing is unnecessary.
Should I buy a bagged mix or make my own for pak choi?
A good peat-free houseplant compost works for pak choi straight from the bag if you mix in some perlite for air. The DIY ratio above gives a more reliable moisture-to-air balance.
How often should I refresh the soil for pak choi?
Peat-free mixes slump and compact as they hold moisture, so refresh pak choi's mix every 12-18 months to keep air in the rootball even if the pot size is unchanged. Use a pot with a drainage hole but a less-porous material (plastic or glazed) so it does not dry too fast. Bottom-watering keeps the mix evenly moist without sogging the crown.
Keep reading
- Pak Choi care — the full brief (light, water, humidity, problems, pet safety)
- How often to water pak choi — the schedule the mix feeds into
- Repotting pak choi — when and how to refresh the mix
- Soil pH guide — test it and adjust it safely
- Underwatered plant — signs and how to rehydrate it
- Why is my plant wilting? Wet vs dry diagnosis
- Should I water my plant? The simple check first
- Best soil for tomato
- Best soil for pepper
- Best soil for cucumber
- All 1284 soil and potting-mix guides in the Growli library