How to Grow August Koch Water Lily

Wikimedia Commons

August Koch Water Lily

Nymphaea 'August Koch'

flower

August Koch is a tropical day-blooming water lily prized for its stunning deep red flowers with yellow stamens. This vigorous cultivar produces abundant blooms throughout the growing season and is ideal for medium to large water gardens and ponds. The plant features dark green leaves with serrated edges that provide an attractive foil for the striking flowers.

When should you plant August Koch Water Lily in your zone?

Get a personalized planting timeline — when to start seeds, transplant, and harvest — based on your USDA zone and local frost dates. Free to start.

Get my August Koch Water Lily timeline →

Example August Koch Water Lily timeline · Pittsburgh, PA (Zone 6b)

  1. Plant August Koch Water Lily

    Around Apr 17

    Near Pittsburgh's average last spring frost.

  2. Tend & protect

    Late spring–summer

    Watering, feeding, and pest-watch reminders.

  3. First August Koch Water Lily blooms

    Around May 17

    ≈ 30 days after planting

Sample dates for Pittsburgh, PA. Sign up to get exact August Koch Water Lily dates for your own zip code.

Growing Conditions

☀️
Sun: Full sun, 6-8 hours daily for optimal blooming
💧
Water: Submerged in 12-24 inches of still or slow-moving water; tropical lilies prefer warmer water temperatures (75-86°F)
📏
Spacing: 36-48 inches
📅
Days to maturity: 30-45 days to first flowers from establishment
🌱
Planting depth: Plant rhizome in soil at pond bottom or in basket with crown at or slightly above soil surface; submerge container 12-24 inches below water surface

Soil

Type: Heavy loam or clay soil in pond baskets; aquatic planting soil preferred
pH: 6.5-7.5
Amendments:
Well-rotted compost Aquatic plant fertilizer pellets Avoid peat moss which floats

Growing Zones

Find your zone →

Thrives in zones 10-11; can be grown as an annual in cooler zones or brought indoors during winter

10 11

Sign up free to see if August Koch Water Lily grows in your zone — and get a personalized planting timeline.

Get my August Koch Water Lily timeline →

Growth Stages

1

Establishment

2-3 weeks

Newly planted rhizome begins sprouting leaves and roots; initial growth is moderate

Keep water temperature consistently warm (75°F+); apply aquatic fertilizer monthly; ensure adequate sunlight

2

Vegetative Growth

3-4 weeks

Plant develops multiple leaves radiating from the center; leaf pads expand and cover water surface

Thin out excess leaves if crowding occurs; maintain water quality and temperature; continue monthly fertilizing

3

Bud Formation

1-2 weeks

Flower buds emerge from the center of the plant, rising above or at the water surface

Ensure consistent water level; maintain full sun exposure; increase fertilizer frequency to every 2 weeks

4

Flowering

6-8 weeks (throughout growing season)

Day-blooming flowers open in morning sun, displaying deep red petals with yellow stamens; flowers close in afternoon

Remove spent flowers to encourage new blooms; maintain warm water and full sun; continue fertilizing

5

Winter Dormancy

4-5 months

In zones below 10, plant dies back or requires protection; tropical types do not produce tubers for winter storage like hardy types

In cold climates, bring container indoors to a warm location or treat as annual; drain and dry plant if overwintering dormant

Companion Planting

Plan your garden →

Plant with:

Pickerel rush (Pontederia) Cardinal flower (Lobelia cardinalis) Water iris (Iris laevigata) Papyrus (Cyperus papyrus) Marginal water plants in surrounding containers

Avoid planting near:

Allelopathic plants that release chemicals inhibiting growth Aggressive marginal plants that shade the water lily Floating plants that may clog the water (though minor companions like water lettuce are acceptable)

Common Pests

  • Spray with strong water stream or neem oil; introduce natural predators like ladybugs

  • Remove affected leaves; reduce organic debris; maintain healthy water quality

  • Hand-remove; limit to beneficial species; avoid overfeeding snails with decaying plant material

  • Remove affected leaves promptly; ensure good water circulation; avoid standing water stagnation

Uses

🍳

Ornamental Culinary Garnish

Culinary

While not typically eaten, the flowers are food-safe and used to garnish gourmet dishes and specialty beverages. The flowers provide elegant visual presentation for upscale dining. [source]

🏠

Water Garden Focal Point

Household

The striking red blooms make August Koch an excellent centerpiece for decorative ponds, water gardens, and aquatic landscapes. This variety adds vibrant color and visual interest to outdoor water features. [source]

💊

Traditional Water Lily Medicine

Medicinal

In traditional Asian medicine, water lily preparations have been used for their cooling and calming properties. Various Nymphaea species are used in Ayurvedic and Traditional Chinese Medicine. [source]

🎨

Cut Flower Arrangements

Craft

The exotic deep red flowers are prized by florists and floral designers for special event arrangements and botanical displays. Flowers last several days in fresh water when cut in early morning. [source]

🦋

Pollinator and Aquatic Habitat

Wildlife

Water lilies provide essential habitat and food sources for aquatic insects, dragonflies, and beneficial pollinators. The floating leaves offer shelter for amphibians and small fish. [source]

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

Harvest Tips

Water lilies are ornamental plants; flowers can be cut in early morning when fully open and will last 1-2 days in fresh water as cut flowers. Pinch off spent blooms to encourage continuous flowering throughout the season.

Fun Facts

  • 🌱 August Koch is a tropical day-blooming water lily, meaning its flowers open during daylight hours and close in the afternoon—unlike night-blooming tropical varieties that open after sunset.
  • 🌱 The cultivar 'August Koch' was named and developed by water lily breeders and has become a popular choice in botanical gardens and specialized water gardens worldwide for its prolific flowering habit.
  • 🌱 Water lilies have been cultivated for over 3,000 years, featured in ancient Egyptian art and revered in Asian cultures; the lotus (sacred water lily) holds profound spiritual significance in Buddhism and Hinduism.

Gardening Terms

New to gardening? Learn about terms used in this guide:

Join 30,000 gardeners planning their gardens with LizPlants.

Get your personalized August Koch Water Lily planting timeline

Tell us your zip code and we'll calculate exactly when to start August Koch Water Lily seeds, transplant seedlings, and harvest — based on your USDA zone and local frost dates. Includes calendar reminders and printable task lists. Free to start.

Get my August Koch Water Lily timeline →