Repotting guide

When & how to repot Hound's Tongue Fern (Microsorum pustulatum)

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

More about hound's tongue fern

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.

Mature size: Fronds typically 20-60 cm (8-24 in) long; plant spreads to 60-90 cm (2-3 ft) wide as the rhizome creeps.

Watch for — Yellowing or mushy fronds: Overwatering and poor drainage leading to root or rhizome rot. Let the top of the mix dry slightly between waterings, ensure the pot drains freely, and never bury the creeping rhizome.

How to tell hound's tongue fern needs repotting

Repotting on a calendar is less reliable than reading the plant. For hound's tongue fern, watch for these signs:

Roots creeping out of the drainage holes or matting tightly across the soil surface.
The rootball dries out within a day or two no matter how much you water.
Water channels straight down the gap between rootball and pot without wetting the centre.
Steady decline — thin growth, persistent crispy edges — that good humidity and watering have not fixed. Only then is the disturbance of a repot worth the risk for hound's tongue fern.

For the underlying biology of a pot-bound root system and why it stalls a plant, see our guide to spotting and fixing a root-bound plant.

How often to repot hound's tongue fern

Every 1–2 years, disturbing the roots as little as possible. Hound's Tongue Fern's growth habit — evergreen epiphytic fern with a creeping, scaly brown surface rhizome from which upright, simple or slightly lobed, tongue-shaped leathery fronds emerge. spreads laterally rather than forming a tight upright clump; well suited to hanging baskets and wide, shallow pots. — sets the pace. 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.

What size pot to step hound's tongue fern up to

Go up only one size and handle the rootball as little as possible. Hound's Tongue Fern resents root disturbance, so the goal is to slide the intact rootball into slightly more soil — not to tease, wash or prune the roots. A modest step up means less shock and a faster recovery.

Not sure of the exact diameter? Our pot size calculator takes the current pot and root spread and tells you the right next size — it deliberately recommends a single step up, never a big jump.

The best time of year to repot hound's tongue fern

Early spring, just as new growth restarts, is the ideal window for hound's tongue fern. The plant is moving into its strongest growth phase and re-roots into fresh soil quickly. Avoid repotting in winter dormancy or, for flowering plants, while it is in bud or bloom — recovery is slowest then and you risk dropping the flowers.

Step-by-step: repotting hound's tongue fern

Keep disturbance to a minimum. Hound's Tongue Fern resents root disturbance, so the plan is to move the intact rootball — not to wash, tease or prune the roots.
Choose just one size up. Pick a pot only one size larger with drainage, and have moisture-retentive coarse, humusy, epiphyte-friendly fern mix ready.
Slide the rootball out whole. Water the day before, then ease hound's tongue fern out keeping the rootball intact. Gently free only the roots that are circling the very bottom.
Nestle it into fresh soil. Add a base layer of fresh mix, set the rootball in at the same depth, and backfill gently around the sides without packing hard.
Water and protect. Water in, then keep it warm, humid and out of direct sun for a few weeks while it re-roots. Expect a short sulk — that is normal.

Aftercare

Expect hound's tongue fern to sulk for a couple of weeks — that is normal after any root disturbance for this group. Keep it warm, humid and out of direct sun, water just enough to keep the mix lightly moist, and do not panic and overwater while it re-roots. Do not fertilise for about 4 weeks — fresh mix already carries nutrients and feeding freshly disturbed roots scorches them.

The right soil mix for hound's tongue fern

Hound's Tongue Fern wants coarse, humusy, epiphyte-friendly fern mix. Use a very free-draining medium: standard houseplant mix blended with coarse orchid bark, coco coir, and perlite works well. As an epiphyte the creeping rhizome must rest on the surface of the mix, not be buried. Wide, shallow pots or hanging baskets suit the spreading rhizome better than deep containers. Always use fresh mix when you repot — reusing old, broken-down soil reintroduces the compaction and poor drainage you are repotting to fix.

Repotting hound's tongue fern — frequently asked questions

How often should you repot hound's tongue fern?

Every 1–2 years, disturbing the roots as little as possible for hound's tongue fern. Repot hound's tongue fern every 1–2 years, disturbing the roots as little as possible — it sulks for weeks if the rootball is teased apart. Slide it into one size up in spring with fresh coarse, humusy, epiphyte-friendly fern mix, keep it warm and humid afterwards, and never bare-root or hard-prune the roots.

What size pot does hound's tongue fern need?

When is the best time of year to repot hound's tongue fern?

Why does hound's tongue fern sulk after repotting?

Hound's Tongue Fern resents root disturbance, so a wilt or stall for a week or two after repotting is normal, not a failure. Minimise it by keeping the rootball intact, stepping up just one size, and keeping the plant warm, humid and out of direct sun while it re-roots.

Should you fertilise hound's tongue fern after repotting?

Not immediately. Wait about 4 weeks after repotting hound's tongue fern. Fresh mix already contains nutrients, and feeding freshly cut or disturbed roots burns them. Resume your normal feeding routine once you see new growth.