Imperial Red Philodendron (Philodendron 'Imperial Red') is a houseplant worth getting to know properly, and this guide covers exactly how to keep it healthy: light, water, soil, humidity, temperature, feeding, repotting, propagation and the problems that show up when something is off. The care numbers below come from standard horticultural references.
Imperial Red is a self-heading philodendron, which means it grows upright from a central stem rather than trailing or climbing.
Imperial Red Philodendron at a glance
| Care need | What this plant wants |
|---|---|
| Botanical name | Philodendron 'Imperial Red' |
| Light | medium to bright indirect |
| Water | every 1–2 weeks; let top soil dry |
| Humidity | moderate to high |
| Temperature | 65–85°F |
| Pet safety | toxic to cats and dogs |
| Repotting | every 2–3 years |
Light
Give your Imperial Red Philodendron medium to bright indirect light. A spot near an east- or west-facing window is ideal; harsh midday sun through a south-facing window can scorch the leaves, leaving pale, papery patches, while too little light makes the plant stretch, grow small leaves and lose variegation. If your only spot is dim, a grow light helps — our grow-light calculator can work out how many hours your plant needs.
Watering
Water every 1–2 weeks; let top soil dry. Push a finger into the soil before you water: if it is still damp at the depth described, wait; if it is dry, water thoroughly until water runs out of the drainage holes, then let the excess drain away completely and empty the saucer. Never let the plant sit in standing water.
In winter, when growth slows, the soil stays wet longer, so stretch the interval and check the soil with a finger before watering. Our watering calculator gives a starting point based on pot size and soil. When in doubt, wait a day and check the soil again — most houseplants recover from a late watering far more easily than from a wet one.
Humidity and temperature
This plant prefers moderate to high humidity and temperatures of 65–85°F. Most homes sit in the comfortable middle of that temperature range, which is why it does well indoors, but winter is the season to watch: cold draughts from windows and doors, hot dry air from radiators, and sudden temperature swings all stress the plant. Our humidity and temperature checker can tell you whether your room suits this plant.
Soil, potting and repotting
Use a loose, airy mix that holds some moisture but drains freely — ordinary potting soil with perlite and orchid bark mixed in, roughly equal parts. Standard potting soil on its own compacts over time and stays too wet, which is how root rot starts. Always use a pot with drainage holes and empty the saucer after watering.
Repot every 2–3 years. The signs it is time are roots circling out of the drainage holes, water running straight through the pot without wetting the soil, or growth that has stalled even though light and water are right. Move up only one pot size — a pot that is too big holds wet soil the roots cannot use — and repot in spring, when the plant is about to grow.
Feeding
Feed monthly in spring and summer with a balanced liquid houseplant fertiliser at half strength, while the plant is actively growing. Do not feed in autumn and winter, when growth slows — excess salts build up in the soil and cause brown leaf tips. Flush the soil with plain water every few months. Our fertiliser calculator works out the amount from the label rate and your pot size.
Propagation
Propagate from stem cuttings in spring or summer. Cut just below a node — the knobbly bump where a leaf meets the stem — making sure the cutting has at least one node and one leaf. Root it in water or moist sphagnum moss, keeping the node covered and the leaf dry. Roots usually appear in a few weeks; once several centimetres long, pot the cutting in the mix described above. A cutting without a node may root a leaf but will never grow into a new plant.
Common problems and fixes
| Problem | Likely cause | Fix |
|---|---|---|
| Root rot | Soggy soil | See below |
| Yellow leaves | Overwatering | See below |
| Brown leaf tips | Low humidity | See below |
Root rot
Likely cause: soggy soil. Take the plant out of its pot, cut away black, mushy roots with clean scissors, and repot in fresh, dry, free-draining mix in a pot with drainage holes. Then water much less often, only when the soil has dried as described above.
Yellow leaves
Likely cause: overwatering. Let the soil dry more between waterings, check the pot drains freely, and remove the leaf once fully yellow. One yellow old lower leaf is normal ageing; several at once points to watering.
Brown leaf tips
Likely cause: low humidity. Raise humidity, water consistently, and flush the soil with plain water every few months to wash out fertiliser salts. Trim only the brown tip, following the leaf shape.
Our plant disease checker can help match leaf spots, wilting and discolouration to common problems if you are unsure what you are looking at.
Frequently asked questions
How often should I water Imperial Red Philodendron?
Water every 1–2 weeks; let top soil dry. Always check the soil with a finger first rather than watering on a fixed day, because the interval changes with the season and pot size. Water thoroughly when the soil is dry and let the excess drain away.
How much light does Imperial Red Philodendron need?
It needs medium to bright indirect light — a spot near an east- or west-facing window usually suits it well. Too little light gives small leaves and leggy growth; harsh midday sun can scorch the leaves.
Is Imperial Red Philodendron safe for cats and dogs?
According to the data used for this guide, this plant is toxic to cats and dogs. Keep it out of reach of pets that chew plants, and if a pet eats any of it, contact your vet.
When should I repot Imperial Red Philodendron?
Repot every 2–3 years, or sooner if roots circle out of the drainage holes. Move up only one pot size, use fresh free-draining mix, and repot in spring.
Why are the leaves on my Imperial Red Philodendron turning yellow or brown?
Yellow leaves are most often caused by overwatering; brown edges or tips most often by low humidity, underwatering or fertiliser salts. Check the table above before changing anything else.
Related guides
Browse the full houseplants hub for more species care guides, or see the sample Monstera Deliciosa care guide for the same format applied to a climbing philodendron relative.