Red Siam (Aglaonema 'Red Siam') care

Aroids · easy to keep

Red Siam (Aglaonema 'Red Siam') wants medium indirect light; the pink and red kinds want it brighter. Water it every 9 days. Water when the top half of the pot is dry. Aglaonemas tolerate a missed week far better than an extra one. Pot it in standard compost with perlite. Balanced feed at half strength monthly in spring and summer, and repot every 1.5 years. Humidity: room humidity is fine. Toxic to cats, dogs and people if chewed — the sap carries insoluble calcium oxalate crystals, which burn the mouth and throat.

A compact aglaonema with green leaves edged and veined in hot pink-red, on pink stems. Like all the red and pink aglaonemas it needs more light than the silver kinds — the colour is what the extra light buys.

Quick facts

Water: Water every 9 days. Water when the top half of the pot is dry. Aglaonemas tolerate a missed week far better than an extra one.
Light: Medium indirect light; the pink and red kinds want it brighter.
Humidity: Room humidity is fine.
Soil: Standard compost with perlite.
Feeding: Balanced feed at half strength monthly in spring and summer.
Repotting: Repot every 1.5 years.
Toxic to pets: Toxic to cats, dogs and people if chewed — the sap carries insoluble calcium oxalate crystals, which burn the mouth and throat. Keep it off the floor if anything in the house tastes its way through life.
Difficulty: Easy.
Mature size: 40–60 cm tall.
Native to: A cultivated hybrid of Southeast Asian parents.

Watering a Red Siam

Water every 9 days. Water when the top half of the pot is dry. Aglaonemas tolerate a missed week far better than an extra one.

That cadence is the one PlantParlour sets for this species when you name it, and it is deliberately on the cautious side — a plant that asks a day early is safer than one that asks a day late. Log each watering and the reminder moves with the plant rather than with the calendar.

Light

Medium indirect light suits the green and silver varieties, which is why they end up in offices. The pink, red and cream cultivars carry far less chlorophyll and need genuinely bright indirect light to keep their colour and keep growing.

Humidity and temperature

Room humidity is fine. Central heating in winter is what turns a comfortable room into a dry one, and it is the usual reason an established plant suddenly browns at the edges or picks up spider mites.

Soil and potting

Ordinary potting compost with a third perlite. Aglaonemas are not fussy; they only object to sitting wet.

Feeding

Balanced feed at half strength monthly in spring and summer. Stop feeding in autumn and start again when you see new growth in spring — feeding a plant that isn't growing just builds up salts in the pot.

Repotting

Repot every 1.5 years. Every second or third spring. They are slow and are perfectly happy slightly potbound.

Common problems

Yellow lower leaves
Overwatering, or cold.

Fix: Let it dry further between waterings and keep it above 15 °C — they sulk in a draught.
Colour washing out of a pink or red variety
Not enough light.

Fix: Move it brighter, out of direct sun.
Grey mushy patches after a cold spell
Cold damage.

Fix: Remove the damaged leaves and move it away from the window or door that did it.

Propagation

Divide the clump, or root a stem cutting with two or three nodes in water.

A cutting taken in PlantParlour keeps its link to the plant it came from, so a propagation years later still traces back to the mother plant — which is the point if you ever sell or trade it.

Toxicity and safety

Toxic to cats, dogs and people if chewed — the sap carries insoluble calcium oxalate crystals, which burn the mouth and throat. Keep it off the floor if anything in the house tastes its way through life.

Named cultivars and variegations

Aglaonema 'Red Siam' is sold under several cultivar names. Care is the same unless noted; variegated forms carry less chlorophyll, so they grow more slowly and want more light than the plain species.

Cultivar	Also sold as	Water
'Siam Aurora'	Siam Aurora	every 9 days
'Pink Dalmatian'	Pink Dalmatian	every 9 days

Questions people ask

How often should you water a Red Siam?

Water every 9 days as a starting point — that is the cadence PlantParlour sets for Aglaonema 'Red Siam'. Water when the top half of the pot is dry. Aglaonemas tolerate a missed week far better than an extra one. Light, pot size and the time of year all move that number, so treat it as a reminder to go and check rather than a rule.

How much light does a Red Siam need?

Is Red Siam toxic to cats and dogs?

How do you propagate a Red Siam?