How to Grow Oblong Sundew

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Oblong Sundew

Drosera intermedia

flower

Oblong Sundew is a small carnivorous plant featuring distinctive reddish tentacle-like glandular hairs that trap and digest insects. Native to wetlands and boggy areas across North America, Europe, and Asia, it relies on nutrient-poor soil for survival. The plant produces delicate white or pale pink flowers on thin stems above its rosette of carnivorous leaves.

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Example Oblong Sundew timeline · Pittsburgh, PA (Zone 6b)

  1. Plant Oblong Sundew

    Around Apr 17

    Near Pittsburgh's average last spring frost.

  2. Tend & protect

    Late spring–summer

    Watering, feeding, and pest-watch reminders.

  3. First Oblong Sundew blooms

    Around Aug 15

    ≈ 120 days after planting

Sample dates for Pittsburgh, PA. Sign up to get exact Oblong Sundew dates for your own zip code.

Growing Conditions

☀️
Sun: Bright indirect light, 6-8 hours daily; can tolerate part shade; avoid intense direct midday sun in hot climates
💧
Water: Keep soil constantly wet and moist; use distilled water or rainwater, never tap water (minerals kill the plant); maintain high humidity; substrate should never fully dry out
📏
Spacing: 2-4 inches between plants to prevent crowding inches
📅
Days to maturity: 120-180 days from seed to flowering maturity
🌱
Planting depth: Sow seeds on surface of moist sphagnum (do not cover); transplant seedlings at 2-3 weeks old

Soil

Type: Nutrient-poor, acidic peat or sphagnum moss-based soil; mimics natural bog conditions
pH: 4.0-5.5
Amendments:
Sphagnum moss (primary component) Peat moss Sand or fine grit for drainage Avoid fertilizers and nutrient-rich amendments

Growing Zones

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Thrives in zones 3-9, with best performance in cooler temperate regions (zones 4-7)

3a 3b 4a 4b 5a 5b 6a 6b 7a 7b 8a 8b 9a 9b

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Growth Stages

1

Seed & Germination

2-4 weeks

Tiny seeds placed on moist sphagnum surface; germination begins in 2-4 weeks under cool, humid conditions

Maintain high humidity under plastic cover; provide bright light; keep substrate consistently moist; ensure good air circulation to prevent fungal issues

2

Seedling & Rosette Formation

4-8 weeks

Small rosettes of narrow, oblong leaves covered in glistening red tentacles develop; leaves reach 0.5-1 inch length

Maintain distilled water moisture; provide bright indirect light; keep humidity high (70-80%); thin seedlings if crowded; avoid transplanting until 2-3 leaves form

3

Vegetative Growth

4-8 weeks

Rosette expands to 2-3 inches diameter; leaf production accelerates; plant develops deeper red coloration under bright conditions; carnivorous tentacles actively trap insects

Maintain constant moisture with distilled water; ensure bright light; allow natural insect prey to supplement nutrition; do not fertilize; monitor for fungal issues in high humidity

4

Flowering

3-6 weeks

Thin flower stalks emerge from rosette center, reaching 4-8 inches tall; delicate white or pale pink flowers open, typically 5-petaled

Continue consistent watering and bright light; flowers typically self-pollinate; allow flowers to mature for seed production; remove spent flowers to redirect energy if desired

5

Seed Production & Dormancy

4-8 weeks (seed maturation); variable dormancy period

Seed pods develop from fertilized flowers; seeds mature in 2-3 weeks; plant may enter dormancy in autumn/winter depending on climate and season

Allow seed pods to dry on plant before collecting; collect seeds when pods brown; store seeds in cool, dry conditions; dormancy is natural; reduce watering slightly if plant enters dormancy but maintain some moisture

Companion Planting

Plan your garden →

Plant with:

Avoid planting near:

Fast-growing bog plants that shade delicate sundews Nutrient-rich soil amendments Fertilizer-dependent plants Species requiring tap water

Common Pests

  • Improve air circulation with small fan; reduce leaf moisture; remove infected leaves immediately; use well-draining substrate; avoid overcrowding

  • Increase humidity to 70%+; spray gently with distilled water; isolate affected plants; mist regularly

  • Remove manually with soft brush or cotton swab; isolate plant; spray with insecticidal soap safe for sensitive plants (test first)

  • and

    Switch exclusively to distilled water or rainwater; flush substrate with distilled water if already affected; prevent by never using tap water

Uses

💊

Traditional respiratory remedy

Medicinal

Sundew species have been used in traditional European herbalism to address cough and bronchial conditions. The plant produces compounds that have been studied for antispasmodic properties. [source]

🦋

Natural insect control

Wildlife

The carnivorous tentacles actively trap and digest flying insects, providing natural pest control for indoor or outdoor growing areas while demonstrating remarkable predatory adaptation. [source]

🏠

Educational display plant

Household

Oblong Sundew serves as a fascinating living demonstration of plant adaptation and carnivory, making it ideal for educational settings and botanical curiosity. [source]

🎨

Botanical specimen collection

Craft

Pressed sundew leaves with their distinctive glandular hairs create striking botanical specimens for herbals and pressed plant art projects, preserving their intricate structure. [source]

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

Harvest Tips

Sundews are not typically harvested for food or material use. For seed collection: Allow flowers to self-pollinate and mature; collect seed pods when fully dry and brown (typically 4-6 weeks after flowering); store seeds in cool (40°F/4°C), dry conditions for up to 1-2 years. Do not harvest leaves—the plant is delicate and leaf removal damages the carnivorous mechanism.

Fun Facts

  • 🌱 Oblong Sundew's tentacles produce a sticky mucilage that glistens in sunlight, resembling dewdrops—hence the name 'sundew.' Insects attracted to the glistening droplets become trapped, and the plant slowly digests them over several days using enzymes similar to those in animal digestive systems.
  • 🌱 The reddish coloration of the tentacles serves dual purposes: it attracts insects (mimicking nectar or flowers) and indicates high anthocyanin production, which increases under bright light and may protect the plant from UV damage.
  • 🌱 Sundews are among the most efficient carnivorous plants, capable of obtaining 50-80% of their nitrogen through insect digestion, allowing them to thrive in nutrient-poor bog environments where other plants cannot survive.

Gardening Terms

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