Marsh Grass-of-Parnassus

parnassia palustris

Also known as: ["Grass-of-Parnassus","Marsh Starwort"]

Family: Parnassiaceae Genus: Parnassia Category: Flowers

Overview

A perennial herbaceous plant native to wetlands, characterized by its distinctive white flowers with green veins on the petals.

Benefits & Perks

["wildlife attractant (bees, butterflies, birds)","shade tolerant"]

Botanical Classification

Phylum: Magnoliophyta
Class: Magnoliopsida
Order: Apiales
Family: Parnassiaceae
Genus: Parnassia
Botanical Name: Parnassia palustris

Plant Characteristics

Basic Information
  • Category: Flowers
  • Suitable Location: moist, shaded woodland gardens or boggy areas
  • Suitable For:
    Collectors & Enthusiasts Wildlife Supporters
  • Is Weed: No
  • Allergenicity: low
Environmental Needs
  • Climate: {"temperatureRange":"1–25°C"}
  • Hardiness: {"zones":"4–7"}
  • Misting: every 2–3 days to maintain high humidity, especially in dry environments
  • Drainage: Well-draining but moisture-retentive.
  • Soil Type: Moist, humus-rich, well-draining soil; peat-based mix with added perlite or sand.
Maintenance Level
  • Maintenance Level: moderate
  • Toughness Level: moderate
  • Pruning Frequency: As needed, typically after flowering or when dead leaves are present.
  • Pruning Intensity: Light pruning; remove only dead, diseased, or overcrowded stems.
Care Details

Ideal Sunlight Coverage:
Bright indirect light for 4–6 hours daily; tolerates partial shade, especially in warmer months.

Sunlight Tolerance Tips:
Acclimate gradually to brighter light to prevent scorching; protect from direct midday sun; adjust placement based on seasonal light intensity.

Warning Signs: Yellowing leaves, root rot, or stunted growth indicate poor soil conditions or improper watering.

Care Requirements

Care Difficulty
moderate

moderate

Sunlight

partial shade to full shade

Rotate plant weekly for even growth; use sheer curtains to filter intense light; avoid placing near hot windows.

Watering

every 7–10 days, keeping soil consistently moist but not waterlogged

Maintain consistent moisture without waterlogging; water early in the day to allow foliage to dry; use room-temperature water.

Soil

moist, humus-rich, acidic soil with good drainage

pH: Acidic to slightly acidic, pH 5.5–6.5.

Keep soil consistently moist but not waterlogged; avoid heavy clay soils; ensure good aeration.

Temperature

Prefers cool temperatures, ideally 50–65°F (10–18°C); tolerates mild fluctuations but dislikes extreme heat.

Monitor temperature changes; maintain consistent cool conditions; avoid sudden temperature shifts.

Fertilizing

every 4–6 weeks during active growth with a balanced liquid fertilizer diluted to half strength

Apply fertilizer in the morning for better absorption; flush soil occasionally to prevent salt buildup; stop fertilizing before dormancy.

Propagation

Methods

Stem cuttings or division of rhizomes; stem cuttings are more common for home growers.

Step-by-Step Propagation Guide
  1. Take a healthy stem cutting.
  2. Dip in rooting hormone if using.
  3. Plant in moist propagation medium.
  4. Maintain humidity and warmth.

Best Time: Early spring or late summer when the plant is actively growing.

Environment

High humidity (70–80%), indirect light, and temperatures around 60–65°F (15–18°C).

Medium

Peat-based mix with perlite or sand for good drainage.

Hormone

Rooting hormone is optional but can improve success rates.

Timeline

Roots may develop in 4–6 weeks; new growth may take an additional 2–3 months.

Tools Needed

Sharp scissors, rooting hormone, propagation tray, humidity dome.

Quick Tips

Use healthy, non-flowering stems for cuttings; maintain consistent moisture; avoid direct sunlight during rooting.

Pruning & Repotting

Pruning Guide
Method

Snip stems just above a leaf node or bud; avoid cutting into healthy growth.

Pruning Plan

Minimal pruning required; focus on removing dead or damaged foliage to maintain plant health and appearance.

Tools

Clean, sharp scissors or small pruning shears.

Checklist

Disinfect tools before use; prune during dry conditions; remove only necessary parts.

Repotting Guide
Best Season

Early spring before new growth begins.

Pot Size

Increase pot size by 1–2 inches in diameter; ensure good drainage holes.

Method

Gently remove the plant; trim any dead roots; repot in fresh, well-draining soil with a slightly larger pot.

Suggestions

Repot every 2–3 years or when the plant becomes root-bound; beneficial for rejuvenation.

Checklist

Use fresh potting mix; ensure proper drainage; handle roots gently; water lightly after repotting.

Advanced Care Tips

Watering Mastery
Watering Checklist

Check soil moisture before watering; water deeply but infrequently; ensure proper drainage.

How to Apply Water Properly

Water thoroughly until it drains from the bottom, ensuring even moisture distribution; focus on the root zone, avoiding wetting the foliage; allow excess water to drain completely.

Pro Tip: Use a watering can with a fine nozzle to avoid disturbing the soil surface.
Watering Schedule Tips

Water regularly during active growth, allowing soil to dry slightly between waterings; reduce frequency in winter dormancy.

Soil Improvement

Add organic matter like peat moss or compost; incorporate perlite or sand for aeration and drainage.

Temperature Stress Management
Signs of Temperature Issues

Wilting, yellowing leaves, or stunted growth in heat; leaf drop or browning in cold stress.

Cold Stress

Low temperatures can slow growth or cause root damage; frost exposure may lead to tissue injury.

Solution: Protect from frost with a cold frame or mulch; avoid placing near drafty windows or doors.

Hot Stress

Excessive heat can cause leaf scorch, dehydration, and reduced flowering.

Solution: Provide shade during peak heat; increase humidity with misting or a pebble tray; ensure adequate ventilation.

Fertilizing Guide
Fertilizing Checklist

Dilute fertilizer correctly; apply during growing season; avoid over-fertilization.

Fertilizing Method

Use a balanced liquid fertilizer diluted to half strength every 4–6 weeks during active growth; avoid fertilizing in winter.

Common Problems & Solutions

Yellow leaves in Parnassia palustris may indicate nutrient deficiencies, overwatering, or pest infestations, affecting the plant's overall health and photosynthetic efficiency.

Wilting in Parnassia palustris is often a sign of water stress, either due to drought or root issues, which can lead to reduced growth and potential plant death.

Leaf spots on Parnassia palustris may be caused by fungal or bacterial infections, resulting in reduced photosynthesis and potential leaf drop.

Rotting, particularly root rot, can occur in Parnassia palustris if the soil is waterlogged, leading to decay of root systems and eventual plant decline.

Toxicity Warning

Cats
Non-toxic

Parnassia palustris is not considered toxic to cats. The plant lacks compounds known to be harmful to felines.

⚠️ Symptoms:
none
🌿 Toxic Parts:
entire plant
⚡ Toxic If:

if eaten

No specific precautions are needed for cats, but ingestion in large quantities may cause mild digestive upset.
Dogs
Non-toxic

Parnassia palustris is not considered toxic to dogs. The plant does not contain known toxic compounds that would cause adverse effects in canines.

⚠️ Symptoms:
none
🌿 Toxic Parts:
entire plant
⚡ Toxic If:

if eaten

No specific precautions are needed for dogs, but as with any plant, ingestion in large quantities may cause mild digestive upset.
Humans
Non-toxic

Parnassia palustris is generally considered non-toxic to humans. However, ingestion of large quantities may cause mild gastrointestinal discomfort due to its high fiber content and potential irritant effects on the digestive tract.

⚠️ Symptoms:
nausea mild stomach discomfort
🌿 Toxic Parts:
entire plant
⚡ Toxic If:

if eaten in large quantities

While non-toxic, it is advisable to avoid consuming large amounts of the plant to prevent potential gastrointestinal upset.

Frequently Asked Questions

Q: Is Parnassia palustris toxic to pets?

A: No, it is non-toxic to dogs and cats.

Q: Where does Parnassia palustris grow naturally?

A: It is native to wetlands and damp meadows in temperate regions.

Q: What are the distinctive features of its flowers?

A: The flowers are white with green veins on the petals and have a unique basal nectary disk.

Quick Reference
Family: Parnassiaceae
Care: moderate
Light: partial shade to full shade
Water: every 7–10 days, keeping soi
Suitable For: ["collectors/enthusiasts","wildlife supporters (attracts bees, butterflies, birds)"]
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