Chilli Growing Guide (Coco Coir Based)¶
This is a practical, no-nonsense reference for growing chillies in coco coir, using perlite, vermiculite, chilli feed, and seaweed.
1. Coco Coir: Is it Suitable?¶
Yes — coco coir is excellent for chillies.
Chillies like:
- Airy roots
- Even moisture
- Consistent feeding
Coco provides all of this, with one catch: it contains no nutrients.
Rules for success with coco:
- Always add perlite
- Feed earlier and more consistently than compost
- Never let it dry out completely
2. Soil / Medium Mixes (by eye)¶
You do not need precise measurements. Mix by eye in a tray, bucket, or bag.
Seed starting¶
- 70% coco coir
- 30% vermiculite
Purpose: moisture retention and gentle root contact.
Seedlings (true leaves showing)¶
- 60% coco coir
- 20% vermiculite
- 20% perlite
Purpose: balance moisture with oxygen.
Young & mature plants¶
- 60% coco coir
- 30% perlite
- 10% vermiculite
Purpose: fast drainage, high oxygen, steady moisture buffer.
Sanity check (squeeze test):
- Falls apart when poked = perfect
- Streams water = too wet
- Dusty = too dry
3. Vermiculite: When to Use It¶
Vermiculite:
- Holds water
- Holds nutrients
- Releases both slowly
Use it lightly.
Good uses¶
- Seeds & seedlings
- Coco-based mixes
- Fine-rooted plants
- As insurance against missed watering
Avoid or minimise¶
- Succulents & cacti
- Mediterranean herbs
- Plants that hate wet roots
Rule: perlite first, vermiculite second.
4. Watering Chillies in Coco¶
What not to rely on alone¶
- Drip tray dryness
A dry tray does not guarantee the root zone needs water.
Better rule¶
Water when:
- Drip tray is dry and
- Top 1–2 cm of medium is dry
- Pot feels lighter
How to water¶
- Water slowly
- Stop at first runoff
- Empty tray after 10–15 minutes
Avoid:
- Tiny daily sips
- Letting coco go bone-dry
5. Feeding Overview¶
Key idea¶
- Fertiliser = food
- Seaweed = stress support
Seaweed is not a fertiliser.
6. Feeding Calendar (Simple)¶
Seeds (0–2 weeks)¶
- Feed: none
- Seaweed: none
Seedlings¶
- Chilli fertiliser: ¼ strength every 10–14 days
- Seaweed: ¼ strength every 3 weeks (optional)
Young plants (15–30 cm)¶
- Chilli fertiliser: ½ strength weekly
- Seaweed: every 3–4 weeks
First flowers¶
- Chilli fertiliser: weekly (½–¾ strength)
- Seaweed: one dose at flower onset
Fruiting¶
- Chilli fertiliser: weekly
- Seaweed: only if stressed
7. When to Use What¶
Use fertiliser when:¶
- Growth is slow
- Leaves are pale
- Plant is actively growing or fruiting
Use seaweed when:¶
- After potting on
- After temperature stress
- Flowers are dropping
- Plant looks sulky but green
Use neither when:¶
- Soil is soggy
- Roots are unhappy
Fix water first.
8. Symptom Decoder¶
Leaf signals¶
- Pale green: needs more feed
- Dark green, no flowers: too much nitrogen
- Yellow lower leaves: underfeeding (common in coco)
Root signals¶
- Droopy leaves + wet soil: overwatering
- Sudden collapse: root rot
- Curling leaves + dry medium: too dry
Flower & fruit issues¶
- Flower drop: stress or inconsistent watering
- Split fruit: irregular watering
9. Ericaceous Compost¶
Ericaceous compost is acidic.
Good for¶
- Blueberries
- Rhododendron
- Azalea
- Camellia
- Magnolia
- Acer
Not ideal for¶
- Chillies
- Tomatoes
- Most houseplants
Safe mixed use¶
- Max 10–20% of a blend
- Only if you want to gently lower pH
10. Core Principles to Remember¶
- Coco wants consistency
- Perlite prevents rot
- Vermiculite buffers mistakes
- Feed little and often
- Seaweed is occasional, not routine
Healthy roots solve most problems