Glass Jar Garden

Plants

Lemon button fern as drawn in the simulator

Lemon button fern

Nephrolepis cordifolia 'Duffii'

BeginnerFine in a closed jar

Rows of tiny round leaflets, lemon scented. Tougher than most ferns.

What the simulation uses

Light
2,500 to 10,000 lux
The brightness it grows well in.
Humidity
50 to 85 % RH
Air moisture it is happy in; below the lower end it dries out.
Temperature
16 to 26 °C
Comfortable range; outside it growth slows.
Dies at
below -5 or above 33 °C
Days beyond these temperatures kill it.
Soil pH
5 to 7 pH
Soil acidity it prefers.
Grows up
1 cm/month
How fast it gains height in good conditions.
Spreads
1.25 cm/month
How fast its edge creeps outwards.
Copes with wet
fair
How well it stands soggy soil; poor means rot comes quickly.
Copes with still air
good
Sealed jars have still air; poor means grey mould finds it.
Copes with shade
good
How well it holds on in dim light.
Copes with drying
good
How well it survives the jar drying out.
Water use
0.1 ml/cm²/day
Water drawn up from its roots per cm² of leaves in room air; a sealed jar cuts this to a fraction and returns it down the glass.
Leaf drop
4.5 %/month
Share of its leaves it sheds each month as litter for the cleanup crew.
Soft leaves
no
Soft new growth that hungry isopods will nibble.
Full size
25 cm tall, 30 cm wide
Its size when grown, before the lid stops it.

Care

Day length
12 to 14 h
Substrate
Moist

What kills it

Description

This dwarf fern handles dry spells and poor conditions better than most of its kind. It spreads by creeping stems and small tubers. Its neat shape makes it a popular centrepiece in jars.

Also called Nephrolepis 'Duffii'.

Estimated, where sources were thin: cultivar size (species values given); growth rates; humidity_rh_pct.

Sources

Grow it in a jar