How to grow ferns from seed (spores)
Ferns don’t grow from seeds in the usual sense — they grow from spores. That makes them slower and more delicate to start, but not difficult if you follow the process.
This is more about patience and hygiene than anything else.
Quick answer: how to grow ferns from spores
Sow fern spores on the surface of sterile, moist compost, keep them covered and humid, and place in bright, indirect light. They develop slowly, first as a green film, then into small plants over several weeks or months.
5 step guide to growing ferns from spores
Step 1: Prepare a sterile growing medium
- Use fine, sterile compost (important)
- Some growers microwave or bake compost to sterilise it
- Firm lightly and moisten before sowing
Step 2: Sow spores on the surface
- Sprinkle spores very thinly (they’re dust-like)
- Do not cover — they need light
- Less is more here
Step 3: Seal and create humidity
- Cover with a clear lid or plastic
- Keep humidity high at all times
- Do not let the surface dry out
Step 4: Provide stable conditions
- Place in bright, indirect light
- Keep warm (around 18–22°C)
- Avoid direct sunlight
Step 5: Be patient and grow on
- First stage looks like a green film (prothallus)
- Small fern plants appear later
- Transplant once large enough to handle
Best varieties & why
- Boston fern (Nephrolepis)
- Common and relatively forgiving
- Good for beginners
- Maidenhair fern (Adiantum)
- Beautiful but slower and more delicate
- Tree ferns
- Slow-growing but impressive long-term
- Asplenium (bird’s nest fern)
Start with Boston or Asplenium — they’re far more forgiving.
Common issues, pests & diseases
No growth at all
- Cause: spores dried out or poor conditions
- Fix: maintain constant humidity
Mould or contamination
Seedlings collapsing
Best fertiliser, soil, lighting & growing conditions
- Light
- Soil
- Fine, sterile, moisture-retentive compost
- Water
- Constant moisture, but not waterlogged
- Humidity
- High humidity is essential
- Feeding
Ferns need stability — not fluctuation.
Time of year
- Best started in spring or early summer
- Warmer temperatures improve success
- Can be done year-round indoors if conditions are stable
Climate and regional notes
UK & Ireland
- Indoor growing recommended
- Humidity is easier to maintain indoors
Europe
- Northern regions similar to UK
- Southern regions may need shade and moisture control
USA
- Indoor propagation works best
- Outdoor success depends on humidity levels
Pro tips for better success
- Always prioritise cleanliness — contamination ruins batches
- Don’t open containers too early
- Label everything clearly
- Expect slow progress — weeks to months
- Treat it like a controlled environment, not normal seed sowing
10 frequently asked questions about growing ferns from spores
Are fern spores the same as seeds
No — they are much smaller and behave differently.
How long do ferns take to grow from spores
Several weeks to months before plants appear.
Why is nothing happening after sowing
Likely conditions are too dry or too cold.
Do fern spores need light to germinate
Yes, they should not be covered.
Can I grow ferns from spores indoors
Yes, this is the best method.
Why is there green film but no plants
This is normal — it’s the first stage of growth.
Can I use normal compost
Not recommended — sterilised compost works best.
How often should I water
Keep consistently moist — never let dry out.
When can I transplant ferns
Once small plants have formed and are large enough to handle.
Is growing ferns from spores difficult
Not difficult — just slower and more precise than normal seeds.
Related guides