Polyscias aka Aralia

Polyscias is a slow-growing plant, which makes it manageable for indoor cultivation. When grown as a houseplant, it typically reaches 1-2 meters in height over several years, with a spread of about 1-2 meters. In optimal outdoor conditions in tropical climates, some species like Polyscias fruticosa can eventually reach 6-8 meters tall. The slow growth rate means that large, mature specimens are often expensive to purchase. The plants develop an upright, multi-stemmed shrubby form with dense foliage that gives them an elegant, architectural appearance.

Polyscias requires warm temperatures to thrive, ideally between 18-24°C (65-75°F), with the plant being happiest at warmer temperatures around 27°C (80°F). The most critical requirement is avoiding cold—temperatures should never drop below 15°C (60°F), and the plant is highly sensitive to cold drafts. Sudden temperature changes or exposure to cold air can cause the plant to drop its leaves as a stress response. Keep your Polyscias away from air conditioning vents, drafty windows, and exterior doors during cooler months.

Polyscias care should be adjusted seasonally to match the plant's natural growth cycle. During spring and summer (the active growing season), water more frequently, maintain higher humidity, and fertilize monthly with balanced fertilizer at half strength. In autumn and winter, reduce watering frequency as growth slows naturally, stop or reduce fertilizing, and be especially vigilant about maintaining warm temperatures and avoiding cold drafts. The plant may grow very little during winter months, which is normal. Monitor humidity levels carefully in winter when indoor heating can dry out the air significantly.

The genus Polyscias includes several popular cultivated species and varieties. Polyscias fruticosa (Ming Aralia) features delicate, finely-cut fern-like foliage with an oriental appearance. Polyscias scutellaria (Shield Aralia or Dinner Plate Aralia) has distinctive single, round shield-shaped leaves, and its 'Fabian' cultivar is particularly popular with dark purple undersides on its leaves. Polyscias balfouriana (Balfour Aralia) displays compound leaves with 3-5 rounded leaflets and comes in variegated forms like 'Marginata' with creamy-white leaf margins. Polyscias guilfoylei (Geranium Aralia) has coarser pinnate leaves with dentate margins. Each species can be identified by its unique leaf structure.

Polyscias responds well to pruning and can be shaped to maintain a desired form or encourage bushier growth. Prune during the active growing season (spring to early summer) for best recovery. Remove any dead, damaged, or yellowing foliage as needed throughout the year. To encourage a fuller, bushier plant, pinch back growing tips or cut stems just above a leaf node. The plant tolerates hard pruning if it becomes leggy or overgrown, and new growth will emerge from the cut points. Polyscias makes an excellent subject for bonsai due to its tolerance of pruning and slow growth rate. When pruning, wear gloves as the sap can cause skin irritation.

Repot your Polyscias every 2-3 years or when it becomes root-bound. The best time to repot is in spring at the start of the growing season. Choose a pot only slightly larger than the current one (1-2 inches wider) to avoid excessive soil moisture that can lead to root rot. Use well-draining potting mix with added perlite or coarse sand to improve drainage—a mix containing coco coir, perlite, and vermiculite works well. Ensure the pot has drainage holes. Handle the root ball gently and water thoroughly after repotting. The plant may temporarily drop a few leaves after repotting due to transplant stress, which is normal.

Polyscias can be propagated through several methods. Stem cuttings are most common: take 10-15cm cuttings with several leaf nodes, remove lower leaves, and root in moist potting mix or water at temperatures of 21-23°C. Root cuttings (25mm segments) can also be used. Air layering is another effective technique for larger stems. Seeds can be sown when fresh but this method is less practical as plants rarely flower indoors. For all cutting methods, high humidity speeds rooting—use a plastic bag or propagation dome. Root cuttings typically take several weeks to establish. Rooting hormone can improve success rates but is not essential.

Yellow leaves on Polyscias typically indicate overwatering or poor drainage, which leads to root stress or root rot. The plant prefers to be slightly underwatered rather than overwatered. Check that the pot has adequate drainage holes and that you're allowing the top 2-5cm of soil to dry between waterings. Other causes include insufficient light (move to brighter indirect light), nutrient deficiency (feed with balanced fertilizer during growing season), or natural leaf aging where older lower leaves yellow and drop. If yellowing is accompanied by soft, mushy stems, root rot may have set in and you should inspect the roots immediately.

Brown leaf tips or edges on Polyscias usually indicate low humidity or inconsistent watering. These tropical plants need moderate to high humidity levels—aim for 50-60% or higher. Increase humidity by placing on a pebble tray, grouping with other plants, or using a humidifier. Brown crispy spots may indicate direct sunlight burn; move to bright indirect light only. Brown mushy patches suggest overwatering and potential fungal issues. Underwatering causes dry, brown, papery leaves that curl. Cold drafts or sudden temperature drops can also cause browning. Check your watering schedule and environmental conditions to identify the cause.

Drooping in Polyscias is most commonly caused by underwatering—check if the soil is very dry and water thoroughly if needed. However, overwatering and root rot can also cause drooping as damaged roots cannot supply water to the plant; in this case, the soil will be wet and roots may appear brown and mushy. Temperature stress from cold drafts or sudden temperature drops causes drooping and leaf drop. Low humidity can also contribute to wilting. First check soil moisture, then assess temperature and humidity conditions. If the plant is severely underwatered, it should recover within a few hours after thorough watering.

Polyscias is notorious for dropping leaves in response to environmental stress, and this is often the first sign that something is wrong. The most common triggers are cold drafts, sudden temperature changes, or temperatures below 15°C (60°F). Other causes include inconsistent watering (both too much and too little), low humidity, insufficient light, or being moved to a new location. Some leaf drop after repotting or when first bringing the plant home is normal adjustment behavior. To minimize leaf drop, keep temperatures consistently warm, avoid drafts, maintain stable humidity, and keep the plant in one location rather than moving it frequently.

Common pests on Polyscias include spider mites (especially in dry conditions), mealybugs, scale insects, aphids, and whiteflies. Spider mites thrive when humidity is low, so maintaining good humidity helps prevent them. Check the undersides of leaves regularly for pests. Root rot is the most serious disease threat, caused by overwatering and poor drainage—ensure your pot drains well and avoid waterlogged soil. Shoot blight and fusarium wilt can also occur, causing stem dieback. Nematodes may affect plants grown in soil. For pest control, wipe leaves with neem oil or insecticidal soap. For fungal issues, improve drainage and reduce watering frequency.

Regularly cleaning Polyscias leaves helps the plant photosynthesize efficiently and discourages pests. Wipe leaves gently with a damp cloth to remove dust every few weeks. For species with finely-cut foliage like Ming Aralia (P. fruticosa), use a soft brush or give the plant a gentle shower. Avoid using leaf shine products as these can clog the leaf pores. You can mist the leaves regularly, which both cleans them and increases humidity. When cleaning, wear gloves if you have sensitive skin as the plant sap can cause irritation in some people. Inspect leaves while cleaning to catch any pest problems early.

Aralia requires a bit more attention and knowledge to thrive, making it a suitable plant for those with some gardening experience.

Aralia’s native range is Pacific Islands.

Aralia should be watered regularly, allowing the soil to dry out between waterings.

Aralia loves a well-draining soil. Perlite and vermiculite help with drainage, while coco coir adds organic matter, so a good potting soil mix will have all three. You can improve store-bought soil by adding some perlite to it.

To ensure optimal growth, the Aralia prefers bright diffused light for 6-8 hours each day. Insufficient light can result in slow growth and leaf drop, so it's important to find a well-lit location for this plant. Place it near a window, within a distance of 1 meter (3 feet), to enhance its potential for thriving.

The Aralia is not in need of supplementary humidity. Most water is taken in by plants through their roots, thus soil watering is the most efficient way to provide humidity to your plants.

The growth of Aralia is not rapid and it doesn't necessitate any extra fertilization. By replacing its potting soil once a year, it should receive ample nutrition. It is important to note that plants obtain their energy from the sun's rays, not from fertilizers.

Ploi's records do not contain confirmed information on the toxicity of this particular plant. In the event of accidental ingestion of plant material with questionable toxicity by you, a family member, or a pet, it is always a good idea to consult a healthcare professional.