The Core Rule: Color Requires Light
Before anything else, understand this principle: the more colorful the aglaonema variety, the more light it needs. This is not a general guideline. It is the single most useful thing to know about this genus, and getting it wrong is responsible for most of the disappointment people have with Chinese evergreens.
The pink, red, orange, and cream pigments in colorful aglaonema varieties are produced as a physiological response to adequate light. In brighter conditions the plant produces anthocyanins and other accessory pigments alongside its chlorophyll. In low light, the plant abandons those pigments entirely and focuses everything on producing as much chlorophyll as possible, because chlorophyll is what captures light for photosynthesis. Chlorophyll is green. The result is that a brilliantly pink or red aglaonema, placed in insufficient light, gradually produces new leaves that are progressively more green until, eventually, it looks nothing like what you bought.
The plant is not dying. It is adapting. But the adaptation costs it everything that made it interesting.
Light Levels by Variety Group
Aglaonemas fall into three broad groups by color, and each group has different light requirements measured in lux (the standard unit of illuminance).
Green and dark-leafed varieties (Maria, Emerald Beauty, Tigress): These are the genuinely low-light tolerant aglaonemas that earned the genus its reputation. They manage well at 500 to 1,500 lux, which is what you typically find in a north-facing room, a few metres back from a window, or in an office with overhead fluorescent lighting. They grow slowly in these conditions but they grow. A north windowsill giving 800 to 1,200 lux is entirely adequate for these varieties. They do not need bright light and putting them there does not dramatically improve their appearance since they are already expressing their full coloring.
Silver and cream variegated varieties (Silver Bay, Silver Queen, Cutlass): These need a step up. The silver-white patterning contains less chlorophyll than pure green leaf tissue, so the plant needs more overall light to compensate. Target 1,500 to 3,000 lux. An east or west window within a metre or two of the glass is the right position. They will survive a north window but grow more slowly and the silver contrast tends to become less pronounced over time.
Pink, red, and orange varieties (Siam Aurora, Red Valentine, Pink Dalmatian, Sparkling Sarah, Creta): These are the most light-demanding aglaonemas. To maintain their vivid coloring, they need 2,500 to 5,000 lux for most of the day. A bright east or west window, positioned close to the glass, is the minimum. In practice, this means within 30 to 60cm of an east or west window, or in a south window with a light sheer curtain to filter the harshest direct sun. Below 1,500 lux, these varieties begin fading. Below 1,000 lux, the fade accelerates noticeably.
Why Aglaonema Is Marketed as a Low-Light Plant
The low-light reputation for aglaonemas is not entirely wrong. It is applied to the wrong varieties. Garden centres and plant shops often sell colorful pink and red aglaonemas with care labels that say "tolerates low light" because the species as a whole does. The labels do not distinguish between variety groups.
This is how people end up with a Siam Aurora in a dark corner wondering why it looks nothing like the one in the shop. The shop probably had grow lights or large south-facing glass. The dark corner at home is giving the plant 300 lux on a good day. No amount of patience fixes that gap.
Green aglaonemas are among a small, genuinely useful group of houseplants that thrive in low light alongside pothos, ZZ plants, and snake plants. That reputation is deserved and real. It just does not extend to the entire genus.
Which Window Direction Works for Each Type
North window: Suitable only for dark green varieties. Light levels at a north windowsill typically range from 500 to 1,500 lux in summer, dropping to 200 to 600 lux in winter. Maria, Tigress, and Emerald Beauty are appropriate here. Any pink, red, or cream-variegated variety placed at a north window will gradually lose its coloring.
East window: The best all-purpose placement for most aglaonemas. Gentle morning direct sun transitions to bright indirect for the rest of the day. At the sill an east window delivers 2,000 to 6,000 lux in summer. Green varieties are fine anywhere in the room. Silver variegated varieties do well within a metre of the glass. Colorful varieties should be positioned on or just back from the windowsill to capture the morning sun and bright indirect afternoon light.
West window: Similar to east, with afternoon sun instead of morning. Summer west windows can deliver 3,000 to 8,000 lux on the sill, which is enough for the most demanding pink and red varieties. In summer, position colorful aglaonemas slightly back from the glass (30 to 60cm) to prevent the leaves from catching extended direct afternoon sun, which can scorch. In autumn and winter, move them closer.
South window: The highest-light option. The challenge is that direct south sun, especially in summer, reaches 20,000 to 60,000 lux at the glass, which is far more than any aglaonema wants. A sheer curtain drops this to a safer 2,000 to 8,000 lux range. With that filtering, a south window is ideal for even the most demanding red and pink varieties. Without it, set the plant back 60 to 90cm from the glass where the direct beam does not reach.
Why Red Aglaonemas Fade in Low Light
Varieties like Siam Aurora, Red Valentine, and Creta are specifically engineered and selected for vivid red or pink coloring. That coloring is anthocyanin-based. Anthocyanins are secondary pigments produced in many plants under conditions of high light, UV exposure, or mild stress. They serve multiple functions including photoprotection, essentially acting as the plant's sunscreen.
In low light the opposite signals are present. The plant needs to maximize chlorophyll to capture whatever light is available. Producing anthocyanins under these conditions is a waste of resources. The plant simply stops making them. New leaves emerge more green than the previous ones. Over several leaf cycles, the plant transforms from a vivid red-edged specimen into something that looks like a generic green aglaonema, which is exactly what it has become.
Moving such a plant back to a bright window often reverses the trend. New growth comes in with stronger coloring. However, already-green leaves do not recolor. The improvement is visible only in the new leaves produced after the move.
Direct Sun and Burn Risk
All aglaonemas, including the green varieties, are sensitive to harsh direct sun. The forest understory origin of the genus means these plants have never adapted to full exposure. Harsh afternoon or midday sun produces bleached patches, faded streaks, or crispy brown burn marks on the leaf surface. These are permanent on that leaf, though the plant continues producing healthy new leaves once moved to a better position.
Morning sun through an east window before 10 or 11am is typically gentle enough for any aglaonema. This gentle early sun is actually beneficial for colorful varieties because it stimulates anthocyanin production without reaching burning intensity. Late-morning south sun and afternoon west sun in summer are the situations to watch. Either filter it with a sheer curtain or set the plant back from the glass.
Signs of Too Little and Too Much Light
Too little light: Colorful varieties losing their pink, red, or patterning and producing increasingly green leaves. Slow or no new growth during the growing season. Leggy growth with long gaps between leaves as the plant stretches toward the light source. Dark-leafed varieties remaining green but growing extremely slowly or producing no new leaves over many months.
Too much light (direct sun exposure): Pale, bleached, or washed-out patches appearing on the leaf surface. Brown crispy patches on the parts of the leaf that received the most direct sun exposure. Overall leaf color appearing faded rather than vivid. These symptoms appear suddenly, often after the plant is moved to a new position or when the angle of sun changes seasonally.
Popular Variety Breakdown
Maria. The benchmark low-light aglaonema. Deep green with subtle silver-green patterning. Tolerates north windows and genuinely dim conditions. One of the best choices for offices or rooms without windows near natural light.
Silver Bay. Large silvery-green leaves with dark green margins. More attractive than pure-green varieties while still tolerating lower light than the colorful types. A good east window placement gives excellent results. One of the most widely available and reliably handsome aglaonemas.
Pink Dalmatian. Green leaves with irregular pink and cream spots scattered across the surface, giving a painted appearance. Needs a bright east or west window to keep the spotting vivid. In low light the pink spots fade to cream then to a pale green that blends with the background.
Siam Aurora and Red Valentine. Among the most vivid red-edged aglaonemas available. These need the best light you can offer without direct sun. A bright east or west window on the sill, or a south window with a sheer curtain, keeps the red margins sharp. In low light they are among the fastest to revert to green because the intense red color requires proportionally more light to maintain.
Sparkling Sarah. Narrow green leaves with bright pink midribs and scattered pink margins. A striking variety that demands consistent bright indirect light. The pink fades noticeably even at medium light levels. Not a good choice for low-light rooms regardless of what the care label says.
FAQ
How much light does an aglaonema need?
It depends entirely on the variety. Green and dark-leafed aglaonemas (such as Maria and Silver Bay) genuinely tolerate low light and can survive in north-facing windows or dim rooms. Pink, red, and heavily variegated varieties (such as Siam Aurora, Red Valentine, and Pink Dalmatian) need bright indirect light, around 2,500 to 5,000 lux, to maintain their color. In low light these colorful varieties survive but fade to green.
Why is my red aglaonema turning green?
Your plant is not getting enough light. The red, pink, and orange pigments in aglaonema leaves are produced in response to adequate light levels. When light drops below roughly 1,500 to 2,000 lux, the plant prioritizes chlorophyll production (which is green) over these pigments. The solution is to move the plant to a brighter window, ideally east or west-facing, and the new growth should develop stronger color.
Can aglaonema grow in low light?
Green-leafed varieties genuinely can. Aglaonema Maria, Silver Bay, and Emerald Beauty are among the most low-light tolerant houseplants available and will grow at a reasonable rate in a north window. Colorful varieties will survive low light but lose their pink, red, or variegated patterning and slowly revert to green. If you have a dim room, choose a dark-leafed variety from the start.
Can aglaonema tolerate direct sun?
No. All aglaonema varieties are sensitive to direct sun, especially harsh afternoon or midday sun. Direct sun causes pale, bleached, or brown scorch patches on the leaves that do not recover. Keep aglaonemas out of direct sunlight. A few feet back from a south window, or behind a sheer curtain, is the right approach if south is your only option.
Which window direction is best for aglaonema?
For green varieties, a north or east window works well. For pink, red, and variegated varieties, an east or west window is best. South windows work for any aglaonema as long as the plant is set back from the glass or filtered with a sheer curtain to avoid direct sun exposure. Avoid placing colorful varieties in north-facing rooms where light is consistently below 1,000 lux.