Botanical name: Aglaonema spp
Aglaonema (Chinese Evergreen) is an excellent houseplant for the poorly-lit spaces. It is easy to grow and is a good air cleaner. Aglaonemas are native to tropical and subtropical regions of Asia and New Guinea. They are evergreen perennial herbs which are intolerant to cold temperatures below 150C. The chilling injury manifests in dark, greasy-looking patches on foliage. The beauty of Aglaonemas emanates from their colorful large spear-shaped leaves borne on short stems. Aglaonemas are slow growing plants requiring frequent feeding and infrequent repotting. In a study done by NASA (National Aeronautics and Space Administration), Aglaonema modestum was found to be effective in the removal of common VOCs especially benzene and formaldehyde from indoor air.
Several varieties and hybrids are available. It is the green varieties Aglaonema modestum that can tolerate some shade but the near-white varieties need a well-lit environment. The favorite of the group is the Aglaonema silver queen whose foliage is almost entirely silver-grey. Another common variety is the Aglaonema pseudobracteatum (Golden Evergreen) whose leaves are blotched with yellow, cream and pale green. Other varieties are Aglaonema commutatum whose leaves have silver bands, Aglaonema nitidum which is the giant of the group with leaves 18 in. plain green and Aglaonema pictum whose 6 in. long leaves are speckled and velvety among many varieties and hybrids.
Chinese Evergreen prefers semi-shade to bright light. However, the near-white variegated plants require more brighter light. Keep these plants away from direct sunlight as it causes sunburn on the leaves. Learn more on how to ensure your plant receives the correct light in this guide on understanding light for houseplants.
Aglaonema requires to be watered liberally during the growing season while allowing the top 2 in. of soil to dry out slightly between waterings. Reduce watering during the cold season as growth is minimal. Avoid waterlogging as it may lead to root-rot if the soil is soggy. Do not allow the soil to dry out completely as it may lead to leaf drop. Learn more on how to water houseplants.
Average warmth with a minumum of 150C is ideal for Chinese Evergreen. Protect the plant from cold draughts as it is intolerant to very low temperatures which cause the leaves to curl and form brown edges. Find out more on temperature for houseplants.
Average room humidity is ideal for Chinese Evergreen. Mist the leaves occasionally and clean them by damp-wiping with a soft cloth to get rid of dust.
Feed Chinese Evergreen with a balanced water-soluble fertilizer every 3-4 months during the growing period. To prevent the leaves from turning yellow due to copper deficiency, ensure your fertilizer contains this micronutrient. These plants are easily injured by overfeeding therefore withhold feeding in the cold season as growth is minimal and feeding at this time can lead to fertilizer burn. Find out more on feeding houseplants.
Aglaonemas are slow growing thus do not require frequent repotting. Repotting may be necessary after 2-3 years when the plant has outgrown its current pot or the soil needs to be replaced. Repot at the beginning of the growing season. Use a free-draining soil which is rich in organic matter and a pot 1 size larger. Ensure the pot has drainage holes to prevent waterlogging which can lead to root-rot.
Being slow growers, Aglaonemas require minimal pruning. Pruning involves removal of yellow and old leaves by cutting them at the soil level and removal of any inflorescences that may develop in order to prolong the life of the plant. Learn more on how to prune houseplants.
Aglaonemas can be propagated during the growing season from offshoots or from stem cuttings.
Propagating Chinese Evergreen from offshoots
Carefully seperate the Aglaonema off-shoots from the mother plant. Ensure each offshoot bears some roots. Pot the offshoots in moist soil in individual pots and place the set up in a warm place away from direct sunlight. Maintain the soil moist through out. In about 5-10 days the shoots should develop their own root system.
Propagating Chinese Evergreen from stem cuttings in soil
Aglaonema stem cuttings root easily and there is no need for rooting hormone. Cut a new shoot bearing about 4-5 leaves or an old stem about 4-6 in. long. Insert the lower cut-end in moist rooting soil. Place the set up in a warm place away from direct sunlight. Maintain the soil moist through out. New growth should sprout in about 3-4 weeks.
Propagating Chinese Evergreen from stem cuttings in water
Place the Aglaonema cuttings in a jar of clean plain water while ensuring that the leaves do not touch the water otherwise they may begin to rot. Place the set up in a warm well-lit spot. Replace the water every 7 days. When the roots are about 3-4 in. long, the cutting can be put in soil. These roots need to be acclimatized to grow in soil by gradually adding soil into the rooting container from when the roots are about 2 in. long so that by the time of transplanting, there is more of soil than water in the rooting container i.e. the roots are more or less growing in moist soil than in water.
Too cold air or cold draughts are the cause of curled leaves and brown leaf edges in Chinese Evergreen. Protect the plant from cold draughts to prevent these.
If the air is too dry, Aglaonema's leaves become shrivelled and form brown leaf tips. Mist the leaves more regularly or set the pot on a wet pebble tray to raise humidity.
This is is an indication of the presence of root-knot nematodes. Aglaonemas are prone to root-knot nematodes whose presence is marked by swellings in the roots. These swellings may reduce water and nutrient uptake resulting in stunted growth and in extreme cases plant collapse.
Aglaonemas are prone to root-rot disease which is enhanced by waterlogging of the soil.
Chinese Evergreen (Aglaonema spp) is toxic to both humans and pets. The plant sap contains calcium oxalate cystals which can cause irritation on sensitive skin; always wear gloves when handling. If ingested, the sap may cause burning in the mouth and throat, vomiting, diarrhea and abdominal pains.