The Philodendron McDowell is a specimen of large heart-shaped velvety leaves that trail. It’s hard to find and costs more than many houseplants. But when you know the basics, they are easy to care for. And they’ll give you long years of indoor greenery.
The Philodendron McDowell loves bright indirect light, warm temperatures, high humidity, and well-draining soil. The McDowell will tolerate most household situations, but the better the conditions, the more impressive it’ll be. If you face a problem, it’ll likely be root rot from overwatering.
Here is a guide on where the Philodendron McDowell comes from and how to keep it healthy.
|Common Name||Philodendron McDowell|
|Scientific Name||Philodendron pastazanum x Philodendron gloriosum|
|Origin||John Banta invented it in 1988 from a cross between Philodendron pastazanum and Philodendron gloriosum, which come from South America. “McDowell” comes from Banta’s friend, Dean McDowell.|
|Growth||Philodendron McDowells are herbaceous, trailing vines. In optimum conditions, outdoor plants reach 6 ft (2 m) long, and indoor plants grow up to 3 ft (1 m). Leaves may get to 2 ft (61 cm) or more.|
|Flowering||Plants that grow outdoors in optimum conditions may flower in the summer.|
|Ease of Care||They are perfect for beginners.|
|Soil||Provide well-draining soil, for example: a cactus mix with organic additions like bark and aeration materials like perlite.|
|Light Requirements||Inside: They grow best with bright, indirect light. Outside: Keep them in partial, dappled sun.|
|Watering Needs||Water thoroughly until draining, then wait until the first 2–3 in (5–7.5 cm) become dry.|
|Temperature||They prefer 55–80° F (13–27° C).|
|Humidity||They survive in 40–60% humidity, which is typical household humidity. But the Philodendron McDowell grows best in 65–75% humidity.|
|USDA Hardiness||Outside, they will grow in zone 9b–11.|
|Potting||Repot in the spring or once the roots reach out through the drainage holes or above the soil. Use a pot size that’s another 2 in (5 cm) wider than the previous pot. It’s best to use a rectangular pot to help the plant crawl from side to side.|
|Fertilizer||Fertilize while watering with a balanced formula once every 4–6 weeks in the spring and summer.|
|Propagating||Propagate Philodendron McDowell by stem cuttings.|
|Care Problems||Be careful about overwatering. The signs include yellowing leaves and dark and mushy stems.|
|Pests||Common pests include aphids, mealybugs, scales, spider mites, thrips, and ticks.|
|Toxicity||Philodendron McDowell has calcium oxalate, which causes GI tract irritation.|
Origins, Appearance, and Growth
The Philodendron McDowell (Philodendron pastazanum x Philodendron gloriosum) is a member of the Araceae or Aroid family.
John Banta invented this cultivar in 1988 and named it after his friend, Dean McDowell. Banta crossed Philodendron pastazanum and Philodendron gloriosum. These parent species come from Columbia, Ecuador, and Peru.
It has dark green, heart-shaped leaves with off-white veins. The texture of the leaf resembles a shiny, velvety gown draping from where the leaf attaches to the petiole.
It grows up to 6 ft (2 m) long as a trailing vine, though most indoor plants reach 3 ft (1 m). Leaves get to 2 ft (61 cm).
Like most tropical houseplants, Philodendron McDowell rarely blooms. An interior environment doesn’t provide longer hours of indirect light like a rainforest would provide. So, plants stick to putting their energy into more important areas like leaves and roots.
If you live in a tropical climate and keep your plant outside, it’ll bloom in the summer.
The Philodendron McDowell needs well-draining soil rich in organic materials. If you want to offer the best soil mix possible, try a custom aroid mix.
For a simplistic approach, making the substrate ⅓ cactus soil, ⅓ perlite or some other aeration material, and ⅓ orchid bark or another organic material is ideal.
Vermiculite is a common perlite alternative. Other organic options include compost, peat, moss, and coco coir. These components in this type of recipe mimic the natural conditions a philodendron would grow in the wild.
The Philodendron McDowell likes bright, indirect light.
If you want it by a window, make sure it’s an east-facing one or one that has a sheer between the window and the plant.
It can survive in lower light conditions, but the leaves will have a weaker, grayer green. It will also grow smaller and have longer petioles from putting energy into searching for light.
Outdoor plants need partial sunlight, preferably only receiving dappled light rather than an extended time of direct light.
If the plant starts to brown and crisp, it’s getting too much direct light.
When watering the Philodendron McDowell, push your finger into the first 2–3 in (5–7.5 cm) of the soil to see if it’s dry. If it’s mostly dry, it’s time to water.
If you’re keeping your Philodendron McDowell outside during the summer, you’ll need to water more in hotter conditions. So, check the soil more often.
The leaves can get damaged from water drops that don’t evaporate, so bypass the leaves and pour directly into the soil. Pass the water over the surface until it fills the drainage tray. This way, roots in every area have equal access to moisture.
Use lukewarm water, as cold and hot temperatures can shock the roots. Dump the excess water that filters into the drainage saucer. This water wicks into the pot and keeps some roots wet, which causes root rot.
Temperature and Humidity
Philodendron McDowell needs 55–80° F (13–27° C) to grow best.
It also loves high humidity. For the best growth, it needs 65–75%.
Below 60%, the leaves may develop yellow or brown margins.
The plant doesn’t tolerate sudden changes in temperature or humidity, so keep the plant away from drafts like open windows and vents.
You can improve your household’s humidity levels with a humidifier, pebble tray, or keep the plant in a humid room like the bathroom.
To a lesser degree, you can also mist the plant regularly or keep it among many other plants. Together, a group of houseplants creates a more humid microclimate.
If you want to keep your Philodendron McDowell outside, it tolerates USDA Hardiness Zones 9b–11. If the weather is warm enough during the summer, you also could place the plant in a shaded area on a patio.
The Philodendron McDowell likes room for its roots and stems to grow. Whenever you see the roots popping out of the draining holes or emerging from the soil surface, it’s time for a new pot.
2 inches wider from the last pot allows for the needed room without leaving too much space for water to sit.
Rectangular pots work best for crawling plants like the Philodendron McDowell.
It’s also best to repot in the spring or when the plant is actively growing. During this season, the plant is prepared to cope with the stress of repotting.
Plants will need repotting about once every 1–2 years. Even if they haven’t grown much, they will need fresh soil.
If they have grown a lot, you can choose to propagate or get a larger pot. They will also prefer wide pots and an open area to trail or a trellis to facilitate horizontal growth as they age.
If you want to fertilize your Philodendron McDowell, use a balanced liquid organic fertilizer diluted by half.
Apply it with your watering routine every 4–6 weeks during the spring and summer, and deliver it a few inches away from the stem. That way, the fertilizer doesn’t sit directly on plant tissue and burn it.
If you recently repotted, there should be plenty of good nutrients in the soil for a few months, and the plant won’t need fertilizer.
You can propagate the Philodendron McDowell with stem cuttings.
The process works best in the spring when the plant becomes active again, and you might be repotting anyway.
The plant should also have at least three leaves.
You can sterilize the scissors by wiping rubbing alcohol over the blades.
- Find and cut a stem off-shoot that has at least one mature leaf (mother leaf), node for a new leaf and several inches of root.
- Place the severed section in a pot and add moss, perlite, or aroid mix.
- Make sure the root is buried, but the stem is just on the surface or slightly pushed in.
- Water enough to make the substrate moist. After a few days, you can water it according to your routine.
Philodendrons are resistant to most common pests, and the McDowell is no exception. But if it is stressed, it can become susceptible to typical household plant pests.
Stressful situations include:
- Living in old soil that has lost its nutrients.
- Not receiving enough water.
- Tolerating unsuitable temperatures.
When this happens, spray neem oil onto a cloth and wipe down the stems and the underside of the leaves. Most sapsucking insects like to hide in these areas. You can also create an insecticidal soap using a spray bottle and mix 1 tsp of dish soap, 2 tsp neem oil, and water.
Signs of common pests for Philodendron McDowell:
- Aphids: Aphids are usually green and sometimes brown insects that blend in with the foliage and hide on the underside.
- Mealybugs: Mealybugs are white, fuzzy, and oval. They infect the soft, newest growth of a plant. They tend to target overwatered and over-fertilized plants.
- Scales: Scales are flat, oval insects with brown markings. They prefer to munch on stems and petioles.
- Spider mites: Spider mites look like black specks and create webs under leaves. They eat chlorophyll and leave white and yellow spots where they forage.
- Thrips: Thrips are elongated yellow, brown, or black insects.
- Ticks: Ticks tend to be dark brown to black and have round, flat bodies. They rarely infest indoor plants but may target your outdoor patio plants.
Philodendron McDowell can pose some issues related to the amount of light and water you provide.
Its big leaves may turn yellow if they receive too little light or overwater.
You can’t save yellow leaves, but you can use their hints to modify your care and keep the rest of the plant healthy.
In worse water situations, the roots will rot if you overwater the plant for so long and the soil has too little aeration mixed in. The Philodendron McDowell will have yellow and wilted leaves, and the stem will look mushy and dark.
Plants eventually die in this state. But you have a chance if you remove it, cut the dead roots, and repot with fresh soil.
Wait longer to water again to give the plant a break before going to a water routine. Make sure to follow the 2–3-inch dryness rule.
On the other hand, green but dull wilted leaves indicate you need to water more.
The Philodendron McDowell contains calcium oxalate, a toxic compound in all Philodendrons.
Calcium oxalate irritates the GI tract and causes symptoms like:
- Lack of appetite
- Pain in the mouth that makes the animal paw at its mouth