How to Grow Smithiantha 'Red King'

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Smithiantha 'Red King'

Smithiantha multiflora 'Red King'

flower

Smithiantha 'Red King' is a striking tropical houseplant known for its velvety, burgundy-red foliage and delicate tubular flowers. This rhizomatous plant produces tall spikes of warm-colored blooms that attract hummingbirds and add dramatic color to indoor gardens. It thrives in warm, humid conditions and makes an excellent specimen plant for collectors seeking something beyond common houseplants.

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Example Smithiantha 'Red King' timeline · Pittsburgh, PA (Zone 6b)

  1. Plant Smithiantha 'Red King'

    Around Apr 17

    Near Pittsburgh's average last spring frost.

  2. Tend & protect

    Late spring–summer

    Watering, feeding, and pest-watch reminders.

  3. First Smithiantha 'Red King' blooms

    Around Aug 15

    ≈ 120 days after planting

Sample dates for Pittsburgh, PA. Sign up to get exact Smithiantha 'Red King' dates for your own zip code.

Growing Conditions

☀️
Sun: Bright, indirect light; 12-14 hours daily optimal; east or west-facing windows; protect from direct afternoon sun which can scorch foliage
💧
Water: Keep soil consistently moist but never waterlogged during growing season; reduce watering in fall as plant enters dormancy; water less frequently in winter; use room-temperature water, preferably rainwater or distilled to avoid mineral deposits on fuzzy foliage
📏
Spacing: 12-18 inches (single plant in pot); provide adequate air circulation to prevent fungal issues inches
📅
Days to maturity: 120-180 days from rhizome planting to first blooms
🌱
Planting depth: Rhizomes planted ½ to ¾ inch deep; do not bury completely

Soil

Type: Well-draining, lightweight, humus-rich potting mix
pH: 6.0-6.5
Amendments:
Peat moss or coco coir Perlite or coarse sand Leaf mold or composted bark Avoid heavy soil that retains excess moisture

Growing Zones

Find your zone →

Zones 11-12; grown as a tender perennial houseplant elsewhere, dormant October-January

11 12

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Growth Stages

1

Dormancy/Rest

October-January, 3-4 months

Plant dies back to ground level after frost or in late autumn; rhizomes remain dormant in soil or stored in cool, dry location

Stop watering; store rhizomes at 50-55°F in dry peat moss or sand; maintain cool conditions to break dormancy; do not disturb rhizomes

2

Sprouting

2-3 weeks

New shoots emerge from rhizomes; small reddish leaves unfurl; delicate stems begin reaching upward

Begin watering when shoots appear; gradually increase moisture; provide warm temperatures (65-70°F minimum); increase humidity; provide 12+ hours of bright indirect light

3

Vegetative Growth

4-6 weeks

Velvety, deep burgundy-red foliage expands; plant produces multiple stems and side shoots; stem height increases rapidly; leaves develop distinctive texture and dark coloring

Maintain consistent moisture; feed weekly with diluted balanced liquid fertilizer; mist foliage regularly to increase humidity (70%+); maintain warm temperatures (70-78°F); rotate pot for even growth

4

Flowering

6-8 weeks per flowering cycle

Tall flower spikes emerge from leaf axils; tubular blooms open progressively along the spike in shades of red, orange, or coral; flowers attract hummingbirds; plant reaches full ornamental value

Continue regular watering and feeding; maintain humidity; provide consistent temperatures; stake tall spikes if needed; remove spent flowers to encourage continued blooming; enjoy for 2-3 months

5

Decline/Senescence

3-4 weeks

Flowering slows; foliage quality diminishes; plant prepares for dormancy; stems weaken

Gradually reduce watering in late summer/fall; reduce fertilizer frequency; lower temperatures to trigger dormancy; maintain bright light; prepare to transition to rest period

Companion Planting

Plan your garden →

Plant with:

Begonias African violets Gesneriads Streptocarpus Episcia Ferns (for textural contrast in terrariums)

Avoid planting near:

Dry-growing succulents Cacti Xerophytic plants requiring minimal water Plants requiring cool dormancy periods that conflict with warmth requirement

Common Pests

  • Isolate plant; spray with insecticidal soap or neem oil; dab with 70% isopropyl alcohol on cotton swab; repeat weekly until resolved

  • Increase humidity; spray with neem oil or insecticidal soap; remove heavily infested leaves; yellow sticky traps to monitor population

  • Increase humidity to 70%+ (prevents infestation); spray with neem oil; mist foliage regularly; isolate affected plants

  • Allow soil surface to dry slightly between waterings; add sand layer on top of soil; use yellow sticky traps; apply Bti if severe

  • Yellow sticky traps; spray with insecticidal soap or neem oil; isolate plant; repeat treatments every 7-10 days

Uses

🍳

No culinary use

Culinary

Smithiantha is purely ornamental and not edible. [source]

🏠

Indoor ornamental display

Household

Grown as a houseplant for its stunning velvety burgundy foliage and vibrant tubular flowers; ideal for terrariums, shade gardens, or warm indoor spaces seeking tropical ambiance. [source]

🎨

Cut flowers and arrangements

Craft

The tall, graceful flower spikes are excellent for tropical-themed floral arrangements and cut flower displays, adding vertical interest and warm color to bouquets. [source]

🦋

Hummingbird attraction

Wildlife

The tubular red and orange flowers are highly attractive to hummingbirds, making this plant valuable for encouraging these pollinators in indoor spaces or warm climates. [source]

💊

Limited traditional use

Medicinal

No significant medicinal applications; however, related Gesneriaceae species have been used in traditional medicine, but Smithiantha is primarily valued ornamentally. [source]

This is not medical advice. LizPlants is not a medical resource. Always consult a qualified healthcare professional before using plants medicinally.

Harvest Tips

Smithiantha 'Red King' is not harvested; rather, it's grown for ornamental enjoyment. Cut flower spikes for arrangements once they've opened several flowers; blooms last 1-2 weeks in water. Allow some flower spikes to remain on plant for continuous blooming. After flowering ends and plant enters dormancy, carefully dig and store rhizomes in cool, dry conditions through winter, or divide rhizomes in spring before replanting.

Fun Facts

  • 🌱 Smithiantha 'Red King' is named for its striking deep red foliage, which intensifies with bright light exposure and cooler night temperatures, creating a dramatic contrast with the vibrant flower spikes.
  • 🌱 The plant is a member of the African Violet family (Gesneriaceae) but is native to Mexico and Central America, not Africa; it thrives in humid, warm conditions similar to tropical cloud forests.
  • 🌱 Rhizomes can be divided in early spring to propagate new plants; a single mature rhizome can produce multiple stems, making division an excellent way to create specimens or share with other plant enthusiasts.

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