Spider plant

Identification and origin

Chlorophytum comosum belongs to the family Asparagaceae. Its natural range runs from tropical West Africa (Sierra Leone to Cameroon) and Ethiopia down to South Africa, through East Africa and Mozambique; many of its wild populations go through a dry winter season. It has naturalized on many islands and in warm regions, from Madeira and the Canary Islands to Australia and New Zealand. The genus name comes from the Greek chloros, “green,” and phyton, “plant”; comosum means “bearing a tuft.”

It is a rosette-forming herbaceous perennial, 12 in – 2 ft tall, with linear, arching leaves 12–18 in long, plain green or striped lengthwise with white. ‘Vittatum’, a favorite, has a white central stripe between green margins; ‘Variegatum’ has the reverse, green leaves edged in white or cream. Below ground, thick tuberous roots store water, helping the plant through dry spells. Long, arching flower stems carry small white star-shaped flowers followed by plantlets at the nodes: in the wild, these touch the ground and root around the mother plant. The runners only form after at least three weeks of short days, with long, uninterrupted nights (less than twelve hours of light a day).

Light

Bright, indirect light a short distance from a window suits it best: an east window, or a south window with the plant set back a little. Some morning sun is beneficial, but direct afternoon sun bleaches and scorches the leaves. It also survives in shade and handles artificial light very well, which makes it an excellent office plant; in low light, however, it loses the brightness and sharp contrast of its variegation.

Watering

Spider plants like consistency. Water with room-temperature water until the whole root ball is moist, water again as soon as the mix is slightly dry, and always empty the saucer. In winter, its resting period, water more sparingly: let the top 0 in of mix dry before watering. Read the leaves: dry, curling, spotted and yellowing leaves call for more regular watering during the growing season; bleached leaves point to inconsistent watering; brown streaks in the middle of the leaf mean too much water during the winter rest. The plant is sensitive to fluoride, chlorine and salts in tap water: if the tips turn brown, switch to rainwater or distilled water. A waterlogged root ball leads to root rot.

Potting mix

A standard houseplant potting mix in a pot with a drainage hole. It likes a neutral pH and good drainage. For mature plants that are producing plantlets, a balanced fertilizer at half strength once a month during active growth is plenty: the tuberous roots store reserves, and too much fertilizer browns the tips and reduces the number of plantlets.

Temperature

Normal household temperatures are comfortable; the ideal range is 55–70 °F. Do not let it drop below 50 °F, and move it away from a cold windowpane in winter; below 45 °F it suffers. Also keep it away from cold air currents and from air-conditioning and heating vents. Pale, limp leaves in winter often mean the room is too warm: the plant is trying to grow while light is too low. It prefers medium humidity but tolerates dry air; a tray of wet pebbles under the pot helps reduce brown tips. Outdoors it stays in the ground year-round only in USDA zones 9a to 11b; elsewhere it can brighten planters or shady beds for the summer.

Repotting

Over time, the fat tuberous roots push the soil up and can distort or split a plastic pot, so repot before it gets that far. Choose a pot only slightly larger, leaving room for the roots without too much empty space, and set the root ball a little below the rim to make watering easier. Repotting can be done in any season. A slightly pot-bound plant produces more plantlets, so expect fewer for a while after repotting. It is also the right time to divide a large clump.

Pruning

Cut off yellowed leaves and, if you like, the brown tips that appear whenever conditions are less than ideal. Plantlets can stay on the plant for years as decoration; if you do not plan to use them, remove them to spare the mother plant’s reserves. Wipe the leaves occasionally with a damp cloth, since dust interferes with photosynthesis.

Propagation

This is one of the easiest plants to propagate. The most reliable method mimics nature: rest a plantlet, still attached to the mother plant, on a small pot of mix, let it root for about two months, then cut the runner once the plantlet resists a gentle tug. Alternatively, wait until a plantlet has at least six leaves and small roots at its base, cut it off, remove the lowest leaves and keep its base in water until the roots reach 1 in or more. A plantlet with no roots can be dipped in rooting hormone and inserted into a damp, peat-based mix. With warmth and indirect light, young plants are ready to move into their own pots in about two months. Dividing the clump also works.

Common problems

One symptom can have several causes: look at the whole plant and its growing conditions before drawing conclusions.

• Brown tips: mix too dry between waterings, very dry air, excess fertilizer, salts, fluoride or chlorine in the water.
• Bleached leaves: extended dryness (often with brown tips), direct afternoon sun, or a room that is too warm in winter.
• Loss of variegation: not enough light; the plant makes more green tissue to compensate.
• Few or no plantlets: overfeeding, light at night, a pot that is too large.
• Root ball drying out too fast: roots have pushed the soil up and out of the pot.
• Root rot: waterlogged mix.
• Pests: whiteflies, spider mites, scale insects and aphids.

Toxicity

No toxicity reported: the spider plant is listed as non-toxic to dogs, cats and horses.