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Verrucosum has a reputation as a difficult collector's plant. It is not difficult so much as specific: it wants humid air and something to climb, and it is unforgiving if you get those two wrong.
Humidity above 60 percent, a damp moss pole to climb, bright indirect light and a chunky mix that drains fast. Get those right and it grows steadily. Get the humidity wrong and the leaf edges brown no matter what else you do.
The two mistakes
Treating humidity as optional. Most philodendrons shrug off dry air. This one does not. It comes from cloud forest, where the air is close to saturated much of the time, and in a dry New Zealand winter room its leaf edges brown and new leaves come through small and damaged.
Wiping the leaves. The velvet texture comes from microscopic structures on the leaf surface, and rubbing it with a cloth flattens them and leaves permanent dull patches. Every instinct you have about keeping glossy foliage clean works against this plant.
What normal looks like
- Deep green leaves with a matte, velvety surface and pale veins standing out clearly.
- Fine soft hairs on the leaf stalks, which is where the name comes from and which are meant to be there.
- New leaves emerging rolled, often in a reddish or bronze tone, darkening as they open.
- Each new leaf larger than the last, provided the plant is climbing.
- Aerial roots reaching from the stem toward the pole.
- Very little growth between May and September.
Where it comes from
Montane cloud forest from Costa Rica down through Colombia and Ecuador into Peru, growing up tree trunks at altitude. Cool, constantly damp, bright but heavily filtered light. That is a specific set of conditions and it explains the plant's reputation.
Philodendron verrucosum grows through the humid montane forests of Central and South America, from Costa Rica south through Panama and Colombia into Ecuador and Peru. Ecuador is where it is most associated, and much of what makes it distinctive comes from the conditions there.
Cloud forest is not the same as lowland rainforest. It sits at altitude, where moist air rises and condenses, so the forest is frequently inside cloud. Humidity stays very high, temperatures are moderate rather than hot, and light reaching the understory is bright but thoroughly diffused. The plant climbs tree trunks as a hemiepiphyte, gripping bark with aerial roots.
The mismatch with a New Zealand living room is almost entirely humidity. Temperature is easy, light is easy, and the plant does not need heat so much as steady damp air. That is why it fails in dry rooms that suit other philodendrons perfectly well, and why its reputation for difficulty is really a reputation for needing one specific thing.
Naming and history
Verrucosum means warty, which is an unkind name for one of the plant's best features: the fine soft hairs covering its leaf stalks.
The species name comes from the Latin verruca, a wart, and refers to the texture of the petioles, the leaf stalks. They are covered in short soft bristly hairs that give them a rough, bumpy appearance. Whoever chose the name was describing the botany rather than paying a compliment.
Those hairs are one of the reliable identifying features. Several philodendrons have velvety leaves, but the combination of a velvet leaf surface with distinctly hairy petioles narrows things considerably. If you are checking whether a plant is a genuine verrucosum, look at the stalks rather than the leaves.
Philodendron as a genus name comes from the Greek philo, loving, and dendron, tree. It describes exactly what these plants do: find a tree and climb it. For verrucosum the name is more than usually apt, since it is among the philodendrons most transformed by having something to climb.
Velvet leaves and hairy stems
The velvet look is a physical structure on the leaf surface that scatters light, not a coating. It can be damaged permanently by rubbing. The pale veins and dark background are a contrast that develops as the plant climbs into better light.
Why it looks like velvet
The matte, suede-like surface comes from the shape of the leaf's outermost cells. Rather than being flat, they are domed or cone-shaped, so light hitting the leaf is scattered in many directions instead of reflecting cleanly. The result is a surface that appears to absorb light and shifts in appearance as you move around it.
There is a working theory that this structure helps understory plants capture scattered light more efficiently in a dim forest floor environment, effectively focusing light into the leaf. Whatever the function, the practical point is that the effect is structural. It is part of the leaf, not a bloom sitting on top of it.
Rubbing a velvet leaf with a cloth crushes those surface cells and leaves a permanently dull, flattened patch. If you need to remove dust, use a soft brush or a gentle stream of tepid water and let it air dry out of direct sun.
The hairy petioles
The bristly hairs on the leaf stalks are the feature the species is named for. They are normal, they are not pests, and they should not be removed. On a healthy plant they are soft and evenly distributed along the stalk.
Leaf size and climbing
Like other hemiepiphytic philodendrons, verrucosum produces small leaves near the ground and progressively larger ones as it climbs. Leaf size is a response to having support, not to age or pot size. A plant on a pole with damp moss for its aerial roots to grip will produce leaves several times the size of one left to sprawl.
The vein contrast also becomes more pronounced on mature, well-lit growth. A young plant in modest light produces smaller leaves with less dramatic veining, and people assume they bought a poor specimen when they simply have a juvenile one.
Growing it
Humidity above 60 percent, bright indirect light, a damp moss pole, chunky airy mix, water when the top few centimetres are dry, moderate warmth. Humidity is the one to solve first.
Humidity
This comes first because it is the thing that decides whether you enjoy the plant. Aim for above 60 percent, and higher is better. Below about 50 percent the leaf edges brown, new leaves emerge smaller and can stick as they unfurl, and the plant looks progressively worse regardless of how well you do everything else.
Practical options in a New Zealand home, roughly in order of effectiveness: a humidifier running near the plant through winter, a bright bathroom, a grouping of plants together, or an enclosed cabinet if you are inclined that way. Misting does not work. It raises humidity for a few minutes and leaves water sitting on a velvet leaf surface, which encourages fungal spotting.
Light
Bright indirect light, thoroughly filtered. In New Zealand, a couple of metres back from a north-facing window or beside an east-facing one, ideally behind a sheer curtain. Direct sun is worse for this plant than for a glossy-leaved philodendron, because the matte surface absorbs rather than reflects and scorches readily.
Too little: small new leaves, long bare stem between leaves, weak vein contrast. Too much: bleached or brown dry patches on the side facing the glass, and a washed-out look to the dark green.
Water
Water when the top few centimetres of mix are dry. Verrucosum likes to stay lightly moist and dislikes both extremes, so it is less drought-tolerant than a heart-leaf philodendron and just as intolerant of sitting wet.
- Check first with a finger to the second knuckle. Damp means wait.
- Water thoroughly at the sink until it runs from the drainage holes.
- Drain completely, then empty the cover pot.
- Water down the pole too, so the aerial roots gripping it stay damp.
Roughly weekly in an Auckland summer, less often in winter. Let the mix tell you rather than the calendar.
Support and climbing
A damp moss pole is close to essential here, more so than for most philodendrons. The plant is built to climb and its aerial roots take up water and nutrients directly once they grip a moist surface. Tie the stem loosely to the pole until the roots take hold, and keep the moss damp.
Coir poles work but dry out faster. Sphagnum-filled poles hold moisture better and suit this plant particularly well.
Temperature
Moderate rather than hot. Comfortable between 18 and 26 degrees, and it tolerates the cooler end better than lowland tropical species because of its montane origin. It stops growing below about 15 and dislikes sudden swings. Keep it off cold glass and out of direct heat pump flow, which is a double problem here since it dries the air as well as chilling or heating the plant.
Potting mix and feeding
Very chunky and airy. Roughly equal parts orchid bark, pumice or perlite, and quality indoor potting mix, with sphagnum or coarse coir added. Many growers use an even more open mix than they would for other philodendrons, since verrucosum roots are fine and rot readily in dense material.
Feed lightly through the growing season, a balanced liquid fertiliser at half strength every three to four weeks October to April, onto damp mix. Stop from May.
Repotting
Every two years or so in spring, one size up only. Handle the roots gently, they are finer than most philodendron roots. This plant resents disturbance more than most, so do not repot on a whim.
Propagation
Stem cuttings with a node, rooted in sphagnum in a humid environment. Air layering is the safer option. Both work reliably provided you keep the humidity up, which is the same thing the parent plant wants.
Stem cuttings
- Choose a section of stem with at least one node, ideally with an aerial root already emerging.
- Cut cleanly about a centimetre below the node with sterilised secateurs.
- Let the cut callus in the shade for an hour or two.
- Root in damp sphagnum moss. For this species sphagnum clearly outperforms water, since water-formed roots adapt poorly and rot risk is higher.
- Keep it in a propagation box or clear bag at high humidity, warm and in bright indirect light.
- Expect roots in three to six weeks. Pot into chunky mix once roots are several centimetres long, and keep humidity high while it establishes.
Air layering
The lower-risk method, and worth using on a plant this valuable. Wrap a node in damp sphagnum, enclose it in cling film or an air layering pod secured above and below, keep the moss damp for four to eight weeks, then cut below the new root mass and pot up. The new plant starts with working roots already attached.
Verrucosum cuttings fail far more often from dry air than from anything else. If you cannot keep a cutting humid, use air layering instead so it never has to survive on its own.
Diagnose a problem
Tick everything you can actually see on your plant. The more you tick, the better this gets at separating causes that look alike.
Water problems
Verrucosum roots are finer than most philodendron roots and rot faster in dense wet mix. The mix matters as much as the watering habit.
Root rot
The main way these are lost. The underlying cause is usually mix that is too dense rather than a heavy hand with the watering can. Fine roots in fine mix stay wet, and this plant has no tolerance for that.
How to identify it
- Several leaves yellowing or drooping at once.
- Drooping despite damp mix, because damaged roots cannot take water up.
- Mix still wet more than a week after watering.
- Stem soft or dark near the mix line.
- A sour smell from the pot.
- Roots brown and soft rather than firm and pale. The definitive test.
How to treat it
- Remove the plant and gently wash the old mix off the roots.
- Cut away every soft root back to firm tissue with sterilised secateurs.
- If the stem is soft at the base, cut above the damage. A healthy top section can be re-rooted in sphagnum.
- Let the cuts dry in the shade for an hour or two.
- Repot into a very open bark and pumice mix in a pot sized to the remaining roots.
- Keep humidity high while it recovers, and wait several days before watering.
Underwatering
Leaves droop, the pot feels light and the mix pulls from the sides. Water thoroughly, or soak the pot for 20 minutes if the mix has gone hydrophobic. Verrucosum is less drought-tolerant than most philodendrons, so do not let it dry out repeatedly. Chronic underwatering shows as brown edges that look identical to low humidity damage.
Light and leaf problems
Direct sun scorches matte leaves faster than glossy ones. Too little light gives small leaves and weak vein contrast. And the velvet surface itself can be damaged permanently by handling, which is not a light problem but gets confused with one.
Sun scorch
Most likely November to February. Damage shows as bleached or brown dry patches on the side facing the window, with sharply defined edges, appearing over days. Move it back from the glass or add a sheer curtain. Scorched tissue does not repair.
Insufficient light
Not damage, just a stall. Small new leaves, long bare stem between them, and vein contrast that is less striking than it should be. Move closer to a north or east-facing window behind a sheer curtain, and rotate the pot at each watering.
Damaged velvet
Dull flat patches on an otherwise healthy leaf, usually matching where the leaf has been handled or wiped. The surface cells that create the velvet effect have been crushed and will not recover. Nothing restores it. The leaf continues functioning normally, and the fix is behavioural: stop wiping, use a soft brush or gentle water for dust, and handle leaves by the stalk.
Pests
Thrips and spider mites are the two to watch. Mites in particular are worth understanding here, because the dry air that lets them thrive is the same condition that damages this plant, so they often appear together.
Velvet leaves mark easily. Rinse rather than scrub, avoid wiping with cloths, and let the plant air dry out of direct sun. Oil-based treatments can leave visible residue on a matte surface, so test on one leaf first.
| Pest | What you see | Where to look | Confirm it |
|---|---|---|---|
| Thrips | Silvery or bronze streaking with tiny black specks, very visible against dark velvet | Inside the furled new leaf, along the midrib and leaf undersides | Tap over white paper. Slender fast insects under two millimetres confirm thrips |
| Spider mites | Fine pale stippling and a dull cast, with webbing in leaf joints | Leaf undersides and where leaf stalks meet the stem | Tap over white paper. Moving specks the size of dust confirm mites |
| Mealybugs | White cottony blobs and sticky residue | Leaf joints, the growing tip, and among the hairy petioles | Touch one with alcohol on a cotton bud. Mealybugs go translucent brown |
Treating thrips
Isolate the plant immediately, rinse gently with attention to the furled new leaf, then treat with Yates Mavrik plus Grosafe Enspray 99 as a wetting agent, available at Mitre 10, Bunnings and garden centres. Repeat every five to seven days for at least four rounds, since eggs laid inside leaf tissue survive contact sprays. Keep checking weekly for a month afterwards.
Treating spider mites
Isolate, rinse gently, then treat with Yates Mavrik or Grosafe Enspray 99 every five to seven days for at least three rounds. Then fix the humidity, because mites thrive in exactly the dry conditions that were already stressing the plant. Solving that solves both problems.
Treating mealybugs
Remove each insect individually with a cotton bud dipped in isopropyl alcohol, being careful not to rub the leaf surface. Follow with horticultural oil every seven to ten days for three to four rounds, testing on one leaf first. Check among the hairy petioles, where they are easy to miss.
Other issues
| What you see | Most likely cause | What to do |
|---|---|---|
| Thin dry brown rim around leaf edges | Humidity too low. The signature verrucosum complaint | Run a humidifier, move to a bright bathroom, or group plants. Do not mist |
| Hairs on the leaf stalks | Nothing. This is what verrucosum means and they are meant to be there | Leave them alone |
| New leaf emerges reddish or bronze | Normal. New growth darkens to deep green as it matures | Nothing |
| Dull flat patch on a leaf | Velvet surface crushed by wiping or handling | Permanent. Stop wiping and use a soft brush for dust |
| Leaves staying small | Nothing to climb, or humidity too low | Add a damp sphagnum pole and raise humidity |
| New leaf could not unfurl properly | Dry air while the leaf was forming | Raise humidity. Do not pull it open |
| Aerial roots dry and shrivelled | Nothing damp to grip | Guide them onto a damp moss pole and water down it |
| Nothing happening at all, in winter | Seasonal dormancy | Reduce watering, stop feeding, keep humidity up, wait for October |
| Stem soft near the mix | Rot advancing from the roots | Act now. See root rot |
Safety and pets
Toxic to cats, dogs and people if eaten. Contains sharp microscopic crystals that cause immediate mouth pain if chewed. Unpleasant rather than usually dangerous.
Like the rest of the arum family, Philodendron verrucosum contains insoluble calcium oxalate as raphides: needle-shaped crystals held under pressure in the plant tissue. When bitten they are released into the soft tissue of the mouth. The effect is mechanical rather than chemical, which is why it hurts instantly rather than hours later.
Symptoms in cats and dogs
- Pawing at the mouth or rubbing the face along the floor.
- Sudden heavy drooling.
- Head shaking and reluctance to eat.
- Vomiting or diarrhoea if a quantity has been swallowed.
What to do
Remove any remaining plant material from the mouth and offer water, milk or a small amount of food to help flush the crystals through. Symptoms usually settle within a few hours. Contact your vet if drooling persists, if there is swelling around the mouth or throat, or if breathing seems affected.
For people
The sap irritates skin and eyes. Wash your hands after pruning, repotting or taking cuttings, and avoid touching your face while you work.
Questions
Is verrucosum really as difficult as people say?
It is specific rather than difficult. Give it humidity above 60 percent, a damp moss pole and bright filtered light, and it grows steadily without much fuss. The reputation comes from people applying ordinary philodendron care, which works for most of the genus and does not work here because of the humidity requirement.
Why are the leaf edges going brown?
Almost always humidity, not watering. A thin dry rim following the leaf edge is the classic sign of air that is too dry, and it is the single most common verrucosum complaint. Run a humidifier near the plant, move it to a bright bathroom, or group it with other plants. Misting will not fix it.
Can I wipe the leaves to clean them?
No. The velvet effect comes from the shape of the outermost leaf cells, and wiping crushes them, leaving permanently dull flat patches. Remove dust with a soft brush or a gentle stream of tepid water, then let the leaf air dry out of direct sun. Never use leaf shine products.
What are the hairs on the stems?
Those are what the plant is named for. Verrucosum means warty, referring to the short bristly hairs covering the leaf stalks. They are entirely normal, they are not pests, and they are one of the reliable ways to identify a genuine verrucosum. Leave them alone.
Does it really need a moss pole?
If you want large leaves, yes. This is a climbing plant and its leaf size is a response to having support, not to age or pot size. A plant left to sprawl produces modest leaves indefinitely. A sphagnum-filled pole works better than coir here because it holds moisture, which the aerial roots use directly.
My new leaf came out smaller than the last one. What went wrong?
Usually humidity or light, occasionally stress after repotting. On a healthy climbing verrucosum each leaf should be larger than the last. A smaller leaf is the plant telling you conditions dropped while that leaf was forming. Check humidity first, then light, then whether it has something to climb.
Can I root a cutting in water?
You can, but sphagnum moss is clearly better for this species. Water-formed roots adapt poorly when moved to mix and the rot risk over a longer period is higher. Damp sphagnum in a humid propagation box gives noticeably better results, and air layering is better again if the plant is valuable to you.