Repotting guide

When & how to repot Philodendron Imperial Red (Philodendron erubescens 'Imperial Red')

Also called Imperial Red Philodendron, Red-leaf Philodendron 'Imperial Red', Blushing Philodendron 'Imperial Red'.

More about philodendron imperial red

About Philodendron Imperial Red

Philodendron erubescens 'Imperial Red' · also called Imperial Red Philodendron, Red-leaf Philodendron 'Imperial Red' · houseplant

Philodendron 'Imperial Red' is a compact, self-heading aroid prized for glossy leaves that emerge deep burgundy-red before maturing to dark green. It thrives in bright indirect light, evenly moist soil, and warmth (18-29C). Easy to grow but toxic to cats and dogs per ASPCA, so keep it out of reach.

Mature size: Roughly 60-90 cm (2-3 ft) tall with a similar 60-90 cm leaf spread indoors; stays compact and does not vine.

Watch for — Yellowing leaves: Usually overwatering or poor drainage. Let the top inch of soil dry between waterings and ensure the pot drains freely. A single older lower leaf yellowing occasionally is normal aging.

How to tell philodendron imperial red needs repotting

Repotting on a calendar is less reliable than reading the plant. For philodendron imperial red, watch for these signs:

Roots spiralling thickly out of the drainage holes or pushing the whole plant up out of the pot.
The pot is so packed that water runs straight through in seconds and barely wets the soil.
It has split a plastic pot, or the rootball is a solid mass with almost no soil left when you slide it out.
Growth and (for philodendron imperial red) flowering have clearly stalled despite good light and feeding — but remember this plant likes being snug, so a little crowding alone is not a reason to repot.

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 philodendron imperial red

Only every 2–4 years, when genuinely crowded. Philodendron Imperial Red is one of the plants that genuinely prefers a snug pot — it grows and flowers better with its roots a little restricted, so resist the urge to repot it on schedule. Self-heading (non-climbing) rosette habit. Leaves radiate from a short, compact central crown rather than vining, so it stays bushy and upright. New leaves unfurl glossy red to burgundy and gradually mature to deep green, often keeping reddish undersides..

What size pot to step philodendron imperial red up to

Go up only one pot size — roughly 2–3 cm (about an inch) wider in diameter, no more. Philodendron Imperial Red positively prefers a snug pot: it flowers and grows better when the roots are a little restricted. The single biggest repotting mistake here is over-potting — dropping philodendron imperial red into a pot two or three sizes up. All that surplus soil holds water the small root system cannot use, stays cold and wet, and rots the roots within weeks. When in doubt, choose the smaller pot.

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 philodendron imperial red

Early spring, just as new growth restarts, is the ideal window for philodendron imperial red. 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 philodendron imperial red

Confirm it actually needs it. Slide philodendron imperial red out and check the roots. Only continue if it is genuinely packed — this plant prefers a snug pot, so if there is still soil and room, put it straight back.
Pick a pot only one size up. Choose a pot just 2–3 cm wider with good drainage. Resist anything bigger; over-potting is the main killer here.
Ease it out gently. Water lightly the day before, then tip philodendron imperial red out, supporting the base. Tease the outer roots free only enough to stop them circling.
Repot at the same depth. Add a layer of fresh loose, well-draining aroid mix, set the plant so the soil line sits exactly where it did before, and backfill around the sides, firming lightly.
Settle it in. Water once to settle the soil, then let it sit. Hold off on more water until the top of the soil dries — fresh soil around a small root system stays wet for a while.

Aftercare

Because the new soil holds more water than the old crammed rootball did, ease right back on watering — let the top of the soil dry before you water philodendron imperial red again, or you will rot the roots in the very pot you just moved it to. Keep it out of harsh direct sun for a fortnight. Do not fertilise for about 4 weeks — fresh mix already carries nutrients and feeding freshly disturbed roots scorches them.

The right soil mix for philodendron imperial red

Philodendron Imperial Red wants loose, well-draining aroid mix. Use a chunky, airy mix that holds some moisture but drains fast, such as quality potting soil amended with orchid bark, perlite, and a little coco coir. Aim for slightly acidic to neutral pH (around 5.5-7.0). Always pot in a container with drainage holes. Always use fresh mix when you repot — reusing old, broken-down soil reintroduces the compaction and poor drainage you are repotting to fix.

Repotting philodendron imperial red — frequently asked questions

How often should you repot philodendron imperial red?

Only every 2–4 years, when genuinely crowded for philodendron imperial red. Only repot philodendron imperial red every 2–4 years, and only when it is genuinely root-bound — it flowers and grows best slightly crowded. Step up just one pot size in spring using loose, well-draining aroid mix. The key mistake is over-potting: a too-big pot stays wet and rots the roots.

What size pot does philodendron imperial red need?

When is the best time of year to repot philodendron imperial red?

Does philodendron imperial red like to be root-bound?

Yes — philodendron imperial red genuinely flowers and grows best when slightly pot-bound, so do not rush to repot it. The mistake to avoid is over-potting into a much larger pot: the excess soil stays wet, the roots cannot use it, and the plant rots. Only repot every few years and only one snug size up.

Should you fertilise philodendron imperial red after repotting?

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