How to Sow Tiny Seeds Correctly

Tiny seeds – such as lavender, pelargonium, sedum, geranium, ornamental grasses and many perennial flowers – may look challenging, but with the right approach they germinate just as well as larger seeds. You only need a few essential rules to help them succeed.

Why tiny seeds need special attention
Because tiny seeds contain little stored energy, they require:
• consistent moisture
• a light, airy substrate
• plenty of light for germination
• very shallow sowing (usually on the surface)
If they are buried too deeply or kept too wet, they often fail to sprout.

The right substrate
Tiny seeds germinate best in a light, sterile, well-draining medium. For example:
• seed starting mix
• coconut coir
• a peat and vermiculite mix (70/30)
The goal is a fluffy, fine-textured substrate without clumps.

How to sow tiny seeds
Fill small pots or trays with a light seed-starting substrate and gently level the surface.
Moisten the top layer with a spray bottle until evenly damp.
Scatter the seeds on the surface.
Do not cover them with soil – most tiny seeds need light to germinate.
Gently press the seeds into the surface so they make contact with the moist substrate.
Cover the container with a transparent lid or film to retain humidity.
Place in a bright spot, away from direct midday sun.

Light – the key to successful germination
Most tiny seeds are light-germinating seeds. That means:
• give them plenty of indirect natural light
• in winter or early spring use a grow light
• provide 12–14 hours of light per day
Not enough light causes seedlings to stretch and become weak.

Moisture and ventilation
Tiny seeds dry out quickly, so moisture must be:
• even
• gentle
• without waterlogging

Tips:
• water with a spray bottle, not a watering can
• ventilate mini-greenhouses daily for 10–15 minutes to prevent mold

How long until they sprout?
Tiny seeds sometimes take longer than larger ones.
Typical germination time:
• 7–21 days for many species
• 30–40 days for slower types
Patience is essential. Keeping conditions stable ensures the best results.

Common mistakes to avoid
• Covering tiny seeds with too much soil
• Overwatering
• Keeping them in low light
• Using heavy or clay-rich soil
• Leaving the humidity dome on too long after sprouting.