Dracaena (corn plant, dragon tree)

About Dracaena (corn plant, dragon tree)

Dracaenas are slow, woody-stemmed foliage plants from tropical Africa and Madagascar that give a room a small tree (NC State). The corn plant carries broad, arching, corn-like leaves, often with a yellow center stripe, on a thick cane; the dragon tree has thin red-edged leaves in tufts on slender, often braided stems. Both put up with low light and dry air but are very sensitive to fluoride in tap water and fertilizer, which shows as brown leaf tips (Clemson).

Hardy outdoors only in zones 10-12 (NC State); it is grown indoors everywhere and can summer outdoors in shade once nights stay above 50 F.

When to plant

Timing is counted from your average last spring frost (and first fall frost). Sow & Tell works out the actual dates for your ZIP code.

Usually bought as a nursery plant, often as a rooted cane; it can also be started from a tip or stem cutting (Clemson).

Growing it indoors

• Light: Most kinds tolerate low light, though leaves grow narrower and thinner; direct sun leaves round dry patches and streaks on the leaves (NC State, Clemson).
• Water: Water thoroughly once the surface is dry to the touch and let it dry slightly between waterings, using room-temperature water; the corn plant likes a bit more moisture in the growing season, and both need less in winter (Clemson, NC State). Dracaenas are very sensitive to fluoride, so if tips brown switch to distilled or rain water and flush the salts out monthly.
• Humidity: Mist or run a humidifier when winter humidity drops below 30-40%; dry air browns the leaf tips (Clemson, NC State).
• Temperature: Keep it above 50 F; it thrives at 70-80 F (NC State), and Clemson suggests 60-70 F days with nights about 10 F cooler. Sudden loss of many leaves follows drafts and temperature swings.
• Feeding: A liquid foliage-plant fertilizer once a month in spring and summer, or time-release pellets, and none in winter; never use a fertilizer containing superphosphate, which is often high in fluoride (Clemson). NC State says the dragon tree needs little feeding.
• Repotting: Repot when the plant starts lifting out of its pot or roots grow out the drainage holes (NC State), one size up in a standard mix without much perlite (Clemson).

Soil

A standard houseplant mix with good drainage, kept near pH 6.0-6.5 and without a high share of perlite, which can carry fluoride (Clemson).

Pot in a standard houseplant mix without a high share of perlite, kept at pH 6.0-6.5 to limit fluoride uptake (Clemson).

Feeding

• Spring and summer: liquid foliage-plant fertilizer, or time-release pellets. Once a month, watered in (Clemson); the dragon tree needs little and does fine on a controlled-release feeding in spring, summer and fall (NC State).
• Fall and winter: none. Stop feeding and let the mix dry a little more between waterings (Clemson, NC State).

Never use a fertilizer containing superphosphate, which often carries fluoride and burns the leaf tips; over-feeding also yellows the tips and margins (Clemson).

Varieties (14)

NC State and Clemson Extension name 14 cultivars of the corn plant and dragon tree; the most common are listed.

Pests to watch for

Thrips, Mealybugs, Scale insects, Twospotted spider mite

Diseases and problems

Root and crown rot, Leaf spot, Fluoride leaf-tip burn

In the kitchen

Safety: All parts contain saponins; eating it irritates the mouth and stomach and can cause nausea, vomiting and diarrhea, and the sap may irritate skin (NC State rates it low severity). Keep it from small children.

Pets: Toxic to dogs, cats and horses (ASPCA, corn plant, Dracaena fragrans): saponins cause vomiting, sometimes with blood, depression, loss of appetite, drooling and, in cats, dilated pupils. NC State lists the dragon tree as toxic the same way.