Philodendron maximum Care and Differences with giganteum

Philodendron maximum, also known as big leaf Philodendron, is a rare and one of the largest leafed Philodendron plants. It has very big ( up to 5.4 feet long), lovely dark green narrowly or oval-triangular arrowhead-shaped leaves with wavy margins and paler main veins.

This aroid is perfect for filling those large spaces in your office, house, or commercial properties giving it a tropical appeal. Also, it will look great outdoors if you have a shaded area and live in the subtropics or tropics.

Learn everything about Philodendron maximum plant, from its appearance to care to propagation to prices to where to buy it. We will also cover how it differs from Philodendron giganteum Schott and something on one of its hybrids, the Philodendron gloriosum x maximum.

About Philodendron maximum

Philodendron maximum K.Krause is an accepted species, originally described by Ernst Hans Ludwig Krause, a German botanist, in 1913. The epithet maxima most likely refer to this plant’s enormous size (leaf size). It is one of the largest known.

• Scientific name: Philodendron maximum
• Common name: Big leaf Philodendron
• Subsection: Psoropodium
• Family: Araceae (aroids)
• Native habitat: Ecuador to Brazil, i.e., Peru, Bolivia, Ecuador, North and West Central Brazil
• Care level: Low maintenance or easy
• Toxicity: It is mildly to moderately toxic to humans, dogs, cats, and other pets since it has insoluble calcium oxalate.
• Propagation: Stem cutting in water or soil

1. Growing habits, size, and growth rate

Philodendron maximum is an evergreen, climbing hemiepiphyte. It grows mainly in tropical wet, and moist forests as an understory plant at elevations of 30-2625 feet above mean sea level, including around Attalea phalerata palm leaf bases.

While it has gigantic leaves, this climbing plant doesn’t grow very large, i.e., it can grow up to 9.8-11.5 feet tall and has a moderate growth rate. However, it will be about 6-8 feet high at home and need a place to climb and a spacious place.

2. How to identify it Philodendron maximum– description

This plant resembles Philodendron giganteum, and some vendors do confuse these two. Let us see in detail how you can identify this plant.

a). Stems

P. maximum has moderately gloss stems, yellow-green in juvenile plants, and thicker and olive-green in mature with short internodes and a ridge on one flattened side.

These aroids have persisting, semi-intact, D-shaped with raised or acute marginal ribs, semi-glossy, medium green cataphylls tinged red or pinkish at the base. They measure about 13.8-19.3 long and will fall once they turn dark brown.

c) Juvenile and mature leaves

Juvenile plants have weakly gloss, slightly bicolorous leaf blades with a broadly spreading sheath on their petioles.

On the other hand, Philodendron maxima will have large, narrowly oval-sagittate to oval-triangular-sagittate sub-leathery dark green leaves, moderately glossy above, matte, and slightly paler below. Their margins undulate and are weakly sinuated (wavy).

These leaves, usually 42.9-65 inches by 11.8 -32.3 inches wide (but they can be 26.3 inches long and as wide as 39.4 inches), are 1.8 longer than wide, with the widest portion where the apex attaches the base.

The anterior lobe has an apex that abruptly acuminates, and 5-8 (but can be 4-9) primary lateral veins arise at 65° degrees to the midrib. These primary lateral veins are usually slightly paler above and moderately lighter beneath and may have a purplish tinge.

What about the midrib? It is also paler above, flat at the base, and obtusely flat-raised toward, while the underside is convex and moderately paler, with sparse, dark-green lineated.

Another thing to look at to identify this aroid is the posterior lobes. Philodendron maxima’s posterior lobes are outward-projecting, often inward-turned and at times overlapping. It has narrowly obovate, mitered, or closed sinuses. These lobes have naked basal rib, 6-7 basal veins, 2-3 front facing, 4-5 back facing, first pair free/almost free to base, two sometimes free, 3-5 fused.

Lastly, it has long (33-5-52-8 inches but can be 16.5 inches long), a bit spongy, semi-glossy petiole with a weakly purplish ring on the apex. These petioles are D or U-shaped with sharp edges, medium to dark green with purple spots near the base, while the middle part is terete and medium green with a dark short lineate and apex subterete.

c). Fruits and flowers

Mature Philodendron maximum will usually have 2 (or up to 6) inflorescences per axil with a spathe and spadix.

These inflorescences have long (longer than spathe or spadix), spreading pendent, semi-glossy medium to dark green peduncles weakly dark lineated. However, the spathe is semi-erect.

The spathe is matte, medium to dark green, and weakly paler outside, while the tube is heavily reddish inside, turning abruptly to white on the blade. Also, the tube has dar, noticeable resin canals on the inner side.

Lastly, infructescence bears pungent scented yellow to yellowish-brown berries.

Philodendron gloriosum x maximum

This hybrid by unknown creators borrows features from both parents and features medium to dark green, arrowhead-shaped leaves with a pinkish margin. Its leaf is slightly larger, more elongated, and less deep green than gloriosum. Also, it is velvety, and the main veins are not as white.

On the other hand, Philodendron gloriosum x maximum has slightly smaller and dark leaves than P. maximum. Also, the main veins are marginally paler, and the leaf is not as dark green.

Perhaps a more wonderful plant you must get a hold of is the Philodendron gloriosum x maximum variegated, with light green to creamy white patches or splashes. However, it is rare and costly, selling at $425-$1500.

Philodendron maximum vs giganteum

Both these two plants have very large leaves and thick stems and resemble each other in many ways, making it difficult for some people to tell them apart.

However, it shouldn’t be hard. Philodendron maximum has narrowly oval-sagittate to oval-triangular-sagittate, sub-leathery dark green with sinuated margin, while P. giganteum leaves are leathery, cordate-oval with smooth to slightly undulating margins and not as dark green.

Also, the main veins in P. maximum are paler than giganteum and have a faint publish ring on the petiole apex, something giganteum doesn’t have.

Caring for Philodendron maximum indoors or outdoors

Philodendron maximum needs a warm, humid place with bright indirect light. Grow it in chunky, airy well-draining soil, and water it when the top few inches feel dry. It also needs feeding, pruning, staking, and repotting.

Here is how to care for this aroid:

• USDA hardiness zone: 10-11, not frost hardy.
• Temperature: 55-80°F. Avoid places near heat sources, cold drafts, or sudden temperature changes. Move outdoors and plant inside when the temperature falls below 50°F.
• Humidity: It prefers high humidity, i.e., 60% or more, but can still thrive in more than 40% humidity. If low, use a humidifier, pebble tray, or mist your plant to raise humidity.
• Light: Bright indirect light but can tolerate medium. Please don’t place this plant in direct sun as it will burn leaves and if your house is poorly lit, buy grow lights.
• Soil: Ideal soil mix should be well-drained, aerated, and rich in organic matter. You can use an aroid mix (See Etsy.com) or add perlite, coco coir, bark chips, and compost/worm castings to potting soil to make yours.
• Watering: I thoroughly water this plant when my XLUX soil moisture sensor reads dry or when the soil feels dry up to the first knuckle of my finger feels dry. Please don’t follow a routine. Instead, test the soil.
• Feeding: Feed once a month with a balanced, liquid fertilizer for houseplants during growing months. I use Miracle-Gro.
• Pruning: Cut any dead, damaged, or diseased leaves with sterilized gardening shears. Also, you can cut back some stems to control the size, especially in early spring before your plant starts growing.
• Repotting: Repot this aroid after every 1-2 years or if rootbound. Use a pot 2-3 inches wider in diameter.  
• Stake: Provide and train your plant on a moss pole, trellis, totem, or vertical climbing surface.

How to propagate a big leaf Philodendron

Propagation of the big leaf Philo is by stem cutting in water or soil. We prefer water propagation as it is straightforward and less messy. But your plant will suffer a little more shock, and water doesn’t have nutrients like soil.

To propagate this plant in water, you need a jar, gardening scissors, 70-90% rubbing alcohol for sterilization, and rooting hormone. A rooting hormone is optional but helps faster rooting. We use HydroDynamics Clonex Rooting Gel.

Here are the steps for propagating P. maximum in water:

1. Select a healthy, mature stem with a few nodes and cut it just below the lower node with your sterilized gardening scissors. If it has more than two leaves, remove the lower ones.
2. Apply your rooting hormone on the cut end.
3. Dip the cut end into a jar with water, ensuring at least a node is under water. However, don’t immerse leaves.
4. Place the cutting in a warm place with bright, indirect light
5. Refill the water when the level goes down and change it after 4-5 days or if it looks cloudy.

After a few weeks, you will see your plant growing some roots at the nodes inside the water. Give them time until they are at least 2-3 inches long before you can transplant the cutting to its growing pot.

 Problems and issues you may face

Pests like aphids, spider mites, scale insects, aphids, etc., and diseases including southern blight or leaf spot (fungal and bacterial) are uncommon indoors. Isolate new plants and practice proper sanitation to avoid infections. And in case of pests, horticultural spray oil, neem oil, or insecticidal soaps will help.

Perhaps, a more likely issue you will have is root rot, especially if you overwater this plant or have a compact, poorly draining potting mix.

Lastly, you have leaf discoloration (yellow, black, or brown spots, including brown tips and edges), leaf curling, and plant drooping. Check if growing conditions are ideal and ensure proper care. Also, diseases, pests, and root rot are possible causes.

Frequently asked questions