Watering schedule

How often to water Hound's Tongue Fern (Microsorum pustulatum) — the schedule

Also called Hound's Tongue Fern, Hound's Tongue, Kangaroo Fern, Fragrant Fern.

More about hound's tongue fern

Watering at a glance

Base rhythm	When the top 2-3 cm of mix begins to dry, roughly every 7-10 days
Spring / summer	Spring and summer: soak or dunk the roots/mount thoroughly about once a week, then let them dry almost completely before the next soak.
Autumn	Autumn: lengthen the gap between soaks as light and growth taper off.
Winter	Winter: soak far less often — roughly every 2-3 weeks — and always let the roots dry fully in between.
Light	Medium indirect light (a couple of metres from a window)

About Hound's Tongue Fern

Microsorum pustulatum · also called Hound's Tongue Fern, Hound's Tongue · houseplant

Microsorum pustulatum is an epiphytic Australasian fern with glossy, leathery, tongue-shaped fronds that spread from a creeping, scaly surface rhizome. It is considerably tougher than many indoor ferns, tolerating average humidity and lower light. Not individually listed by ASPCA; treat with caution around pets until formally assessed.

Ideal humidity: 40-65%

Watch for — Brown frond tips: Usually low humidity, inconsistent watering, or mineral build-up from hard tap water. Raise humidity, water more evenly, and use filtered or rainwater.

The watering schedule, season by season

Hound's Tongue Fern grows on bark, not in soil — it wants its roots soaked then fully dried and exposed to air, never kept damp like a potted plant. The base rhythm for hound's tongue fern is when the top 2-3 cm of mix begins to dry, roughly every 7-10 days, but the real interval moves with the season, the light and the pot — so treat the figures below as a starting point and always confirm with the plant itself.

Spring & summer (active growth): Spring and summer: soak or dunk the roots/mount thoroughly about once a week, then let them dry almost completely before the next soak.
Autumn (slowing down): Autumn: lengthen the gap between soaks as light and growth taper off.
Winter (rest / dormancy): Winter: soak far less often — roughly every 2-3 weeks — and always let the roots dry fully in between.

Keep the root zone evenly moist but never waterlogged. The leathery fronds tolerate brief dryness better than delicate ferns, but prolonged drought causes frond tips to brown. The surface rhizome should not be buried and can be allowed to dry slightly between waterings. Use room-temperature water; hard, chlorinated tap water may cause tip browning.

Want this turned into a live reminder that adjusts to your home and the weather? The Growli watering calculator takes your pot size, light and season and returns a starting interval for hound's tongue fern in seconds.

How to tell hound's tongue fern needs water

A calendar is the worst way to water hound's tongue fern. Check the plant and the soil instead — for this species, look for these signals in order:

Roots turn silvery-grey or chalky instead of green/plump.
The mount or bark medium is bone dry and light.
Leaves or pseudobulbs look slightly wrinkled or less rigid.

The most reliable single check is the first one on that list. When two signals agree, water; when they disagree, wait a day and look again — under-watering hound's tongue fern for a day is almost always safer than over-watering it.

Overwatering vs underwatering hound's tongue fern

The two failure modes can look alike at a glance, so check the soil weight and wetness before you decide. For hound's tongue fern specifically:

Signs you are overwatering

Mushy, brown, hollow roots that have stayed wet too long.
Yellowing, soft leaves at the base.
A persistently wet, never-drying medium.

Signs you are underwatering

Leaves go limp, leathery or accordion-pleated; roots stay grey for long stretches.
Shrivelling pseudobulbs or curling leaves.

Treating hound's tongue fern like a normal houseplant — watering little and often into bark or moss that never dries — suffocates and rots the roots. Soak hard, then let it dry out.

Water quality notes

Rainwater or filtered water is best for hound's tongue fern; many epiphytes are sensitive to softened water and tap-water minerals.

Seasonal and environmental adjusters

Every figure above shifts with the conditions in your home. For hound's tongue fern, the levers that matter most are:

Air movement matters as much as water — roots must dry between soaks to avoid rot.
A bark or mounted medium dries far faster than moss, so the wetter the medium, the longer you wait.
In high humidity you can soak less often; in dry heated rooms, more often but still let it dry.

Pot choice is part of this too — work out the right size with the pot size calculator, since a pot that is too big stays wet long enough to rot the roots of hound's tongue fern.

Hound's Tongue Fern watering — frequently asked questions

How often should I water hound's tongue fern?

Water hound's tongue fern when the top 2-3 cm of mix begins to dry, roughly every 7-10 days. Spring and summer: soak or dunk the roots/mount thoroughly about once a week, then let them dry almost completely before the next soak. Winter: soak far less often — roughly every 2-3 weeks — and always let the roots dry fully in between.

How do I know when hound's tongue fern needs water?

Roots turn silvery-grey or chalky instead of green/plump. The mount or bark medium is bone dry and light. Leaves or pseudobulbs look slightly wrinkled or less rigid. The single most reliable test for hound's tongue fern is the first signal on that list — checking the soil or the plant directly always beats watering by the calendar.

What does an overwatered hound's tongue fern look like?

Mushy, brown, hollow roots that have stayed wet too long. Yellowing, soft leaves at the base. A persistently wet, never-drying medium. Treating hound's tongue fern like a normal houseplant — watering little and often into bark or moss that never dries — suffocates and rots the roots. Soak hard, then let it dry out.

What are the signs of an underwatered hound's tongue fern?

Leaves go limp, leathery or accordion-pleated; roots stay grey for long stretches. Shrivelling pseudobulbs or curling leaves.

Can I use tap water on hound's tongue fern?