How to Grow Large Amazon Sword

iNaturalist

Large Amazon Sword

Echinodorus grandiflorus

herb

Echinodorus grandiflorus is a large, aquatic flowering plant native to South America, commonly used in aquariums and water gardens. It features broad, lanceolate leaves that can reach impressive sizes and produces delicate white flowers on elongated stems above the water surface. This plant is prized for its dramatic appearance and ability to serve as a focal point in larger aquatic systems.

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Example Large Amazon Sword timeline · Pittsburgh, PA (Zone 6b)

  1. Plant Large Amazon Sword

    Around Apr 17

    Near Pittsburgh's average last spring frost.

  2. Tend & protect

    Late spring–summer

    Watering, feeding, and pest-watch reminders.

  3. Harvest Large Amazon Sword

    Around Aug 15

    ≈ 120 days after planting

Sample dates for Pittsburgh, PA. Sign up to get exact Large Amazon Sword dates for your own zip code.

Growing Conditions

☀️
Sun: Bright light, 8-10 hours daily; full spectrum lighting recommended for aquariums (1000+ lumens)
💧
Water: Submerged or partially emergent growth; requires consistent water conditions with regular water changes (25-30% weekly). Prefers stable temperature and moderate to good water circulation without strong direct current.
📏
Spacing: 12-18 inches from other plants; requires substantial space due to large mature size inches
📅
Days to maturity: 120-180 days to full maturity
🌱
Planting depth: Plant rhizome at or just above substrate surface; do not bury the crown

Soil

Type: Nutrient-rich aquarium substrate or aquatic plant soil
pH: 6.0-7.5
Amendments:
Iron supplements Liquid fertilizers (NPK) Trace minerals and micronutrients Root tabs for substrate enrichment

Growth Stages

1

Establishment

2-4 weeks

Plant settles into substrate with initial root development and leaf unfurling

Maintain stable water conditions, apply root tabs, provide consistent lighting; avoid moving the plant frequently

2

Vegetative Growth

6-12 weeks

Rapid leaf production and expansion; plant develops robust root system and establishes significant biomass

Provide regular fertilization, ensure adequate lighting, perform regular water changes, remove any damaged older leaves

3

Pre-flowering

4-8 weeks

Plant reaches maturity; leaves become larger and more numerous; flowering stems begin to develop

Continue balanced fertilization, maintain optimal light and temperature, ensure good water quality

4

Flowering

2-6 weeks

Delicate white flowers bloom on long, emergent stems that rise above the water surface; flowers last several days

Maintain high humidity around emergent portions, continue fertilization, allow stems to extend above water for pollination

5

Post-flowering

Ongoing

Seed development may occur on spent flower stems; plant may produce daughter plantlets if pollinated

Remove spent flower stems, trim any overgrown foliage, continue standard care regimen

Companion Planting

Plan your garden →

Plant with:

Avoid planting near:

Aggressive stem plants that compete for nutrients Delicate tissue-culture plants sensitive to allelopathy

Common Pests

  • Manual removal, reduce feeding of snails, use snail-specific traps, maintain proper population control through predatory fish

  • Reduce lighting duration to 8 hours, perform water changes, reduce nutrient overload, add algae-eating fish (Siamese Algae Eaters, Plecos), use UV sterilization if needed

  • Improve water circulation, reduce organic debris, perform partial water changes, adjust pH if too acidic, remove severely affected leaves

  • Add liquid fertilizers or root tabs, test water parameters, ensure adequate lighting to support nutrient uptake

Uses

🏠

Aquarium focal point plant

Household

Serves as a stunning centerpiece or background plant in large aquariums, creating visual depth and structure. Its impressive foliage and potential white flowers make it highly valued by aquascaping enthusiasts. [source]

🦋

Habitat and spawning substrate

Wildlife

Provides shelter and breeding grounds for fish and aquatic invertebrates, creating complex microhabitats within the aquarium ecosystem. Floating leaves and emergent stems offer surfaces for labyrinth fish to build bubble nests. [source]

🏠

Water purification

Household

Helps absorb excess nutrients (nitrogen, phosphorus) from aquarium water, reducing algae growth and improving water quality. Large plants with substantial biomass are particularly effective biofilters. [source]

🎨

Aquascaping design element

Craft

Used by aquatic designers to create natural, planted tank landscapes following Dutch, Nature, or Jungle Aquarium styles. Its large size and architectural form make it ideal for creating focal points and spatial composition. [source]

Harvest Tips

Echinodorus grandiflorus is typically not harvested for consumption but rather maintained as a living aquatic display plant. Leaves can be trimmed to manage size and shape; remove yellowed or damaged leaves at the base. Flower stems may be removed after flowering. Daughter plantlets, if produced, can be separated once they develop sufficient roots.

Fun Facts

  • 🌱 Echinodorus grandiflorus is one of the largest species in the Echinodorus genus and can reach 24-32 inches in height or more when grown emersed, making it suitable only for larger aquariums or paludariums.
  • 🌱 The plant produces white flowers with multiple petals that bloom on elongated stems; in nature, these flowers are pollinated by insects, but in aquariums, hand pollination is rarely successful.
  • 🌱 Echinodorus species have been used in traditional Amazonian ecosystems for centuries and are sometimes called 'Amazon Swords' due to their sword-like leaves and South American origin.

Gardening Terms

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