Olympic St. John's Wort

hypericum olympicum

Also known as: ["Olympic Hypericum"]

Family: Hypericaceae Genus: Hypericum Category: Flowers

Overview

A perennial shrub native to the mountains of Greece, known for its bright yellow flowers and medicinal properties.

Benefits & Perks

["long-flowering","wildlife attractant (bees, butterflies, birds)","drought tolerant","aesthetic foliage"]

Botanical Classification

Phylum: Magnoliophyta
Class: Magnoliopsida
Order: Malpighiales
Family: Hypericaceae
Genus: Hypericum
Botanical Name: Hypericum olympicum

Plant Characteristics

Basic Information
  • Category: Flowers
  • Suitable Location: rock gardens, sunny borders, or containers in full sun
  • Suitable For:
    Beginners Outdoor Landscapers Wildlife Supporters
  • Is Weed: No
  • Allergenicity: low
Environmental Needs
  • Climate: {"temperatureRange":"5–35°C"}
  • Hardiness: {"zones":"7–9"}
  • Misting: rarely required, only if ambient humidity is very low
  • Drainage: Fast-draining to prevent waterlogging.
  • Soil Type: Well-draining, loamy soil with added organic matter like compost or peat.
Maintenance Level
  • Maintenance Level: moderate
  • Toughness Level: moderate
  • Pruning Frequency: Light pruning annually in late winter or early spring; more intensive pruning after flowering if needed.
  • Pruning Intensity: Moderate; remove up to one-third of the oldest stems to rejuvenate growth.
Care Details

Ideal Sunlight Coverage:
Bright indirect light for 6–8 hours daily; can tolerate full sun with gradual acclimation, especially in cooler climates.

Sunlight Tolerance Tips:
Acclimate to intense sunlight slowly over 1–2 weeks; protect from harsh midday sun; adjust indoor placement to mimic natural light cycles.

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

Care Requirements

Care Difficulty
easy

moderate

Sunlight

full sun to partial shade

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

Watering

every 7–10 days during active growth, reduce in winter

Water thoroughly until it drains from the bottom, allow soil to dry partially between waterings, and avoid overwatering to prevent root rot.

Soil

well-draining, sandy loam with some organic matter

pH: Slightly acidic to neutral (pH 6.0–7.0).

Avoid heavy clay soils; use raised beds for outdoor planting; top-dress with compost annually.

Temperature

Prefers 60–75°F (15–24°C); tolerates cooler temperatures down to 50°F (10°C) but avoids frost.

Avoid sudden temperature fluctuations; maintain consistent room temperature; protect from cold drafts.

Fertilizing

every 4–6 weeks during spring and summer

Fertilize after watering to prevent root burn; flush soil occasionally to prevent salt buildup; avoid over-fertilizing.

Propagation

Methods

Stem cuttings taken from new growth in spring or early summer.

Step-by-Step Propagation Guide
  1. Take 4–6 inch cuttings.
  2. Remove lower leaves.
  3. Dip in rooting hormone.
  4. Plant in medium.
  5. Maintain humidity.

Best Time: Spring or early summer when the plant is actively growing.

Environment

Warm, humid environment with indirect light and consistent temperatures around 70°F (21°C).

Medium

Well-draining mix of perlite and peat moss or cactus potting mix.

Hormone

Recommended to use rooting hormone powder for faster root development.

Timeline

Roots typically form in 4–6 weeks; new growth may appear in 8–12 weeks.

Tools Needed

Pruning shears, rooting hormone, small pots, plastic wrap or propagator, misting bottle.

Quick Tips

Use healthy, non-flowering stems; maintain high humidity; avoid direct sunlight during rooting.

Pruning & Repotting

Pruning Guide
Method

Cut stems just above a leaf node or bud; thin out crowded areas to improve air circulation.

Pruning Plan

Prune to maintain shape, encourage bushier growth, and remove dead or weak stems.

Tools

Sharp bypass pruners, clean scissors, gloves.

Checklist

Sanitize tools; prune during dormancy; remove dead/damaged growth; shape evenly.

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

Remove plant gently; trim rootbound roots; place in a slightly larger pot with fresh soil; water lightly.

Suggestions

Repot every 2–3 years or when roots outgrow the pot; beneficial to refresh soil and provide space.

Checklist

Check root health; prepare new pot; use fresh soil mix; water sparingly post-repotting.

Advanced Care Tips

Watering Mastery
Watering Checklist

Check soil moisture; water deeply; ensure drainage; avoid wetting leaves.

How to Apply Water Properly

Water directly at the root zone, ensuring even moisture distribution without saturating the foliage. Water early in the morning to minimize evaporation and allow leaves to dry.

Pro Tip: Use a watering can with a narrow spout to target the soil precisely and avoid disturbing the plant.
Watering Schedule Tips

Water deeply once the top inch of soil feels dry, typically every 7–10 days in spring/summer, reducing frequency to every 2–3 weeks in fall/winter.

Soil Improvement

Add perlite or coarse sand for drainage; incorporate compost for fertility; ensure soil is loose and airy.

Temperature Stress Management
Signs of Temperature Issues

Wilting, leaf drop, or yellowing in cold; scorching or stunted growth in excessive heat.

Cold Stress

Slows growth, causes leaf discoloration, and may lead to root damage if temperatures drop below 50°F (10°C).

Solution: Move to a warmer location; insulate pots with bubble wrap; avoid placing near drafty windows or doors.

Hot Stress

Leaves may scorch, wilt, or drop; growth may slow due to excessive transpiration.

Solution: Provide shade during peak sun hours; increase humidity with misting or a pebble tray; ensure adequate watering.

Fertilizing Guide
Fertilizing Checklist

Check fertilizer type; dilute correctly; apply during active growth; stop in dormant season.

Fertilizing Method

Use a balanced liquid fertilizer diluted to half strength every 4–6 weeks during spring and summer; cease in fall and winter.

Common Problems & Solutions

Yellow leaves in Hypericum olympicum may indicate nutrient deficiencies, overwatering, or pest infestations such as spider mites or aphids, which disrupt chlorophyll production and photosynthesis.

Wilting in Hypericum olympicum can be caused by water stress, either due to under or overwatering, root damage, or pathogen infection, leading to reduced turgor pressure and impaired nutrient uptake.

Leaf spots on Hypericum olympicum may be caused by fungal or bacterial pathogens, leading to necrotic lesions, defoliation, and reduced photosynthetic capacity, potentially weakening the plant.

Rotting in Hypericum olympicum is often associated with root or stem rot caused by fungal pathogens like Phytophthora or Fusarium, typically resulting from excessive moisture and poor drainage, leading to tissue decay and plant death.

Toxicity Warning

Cats
Slightly Toxic

Cats may experience mild gastrointestinal upset and photosensitivity if they ingest parts of Hypericum olympicum. The effects are generally not severe but warrant attention.

⚠️ Symptoms:
vomiting diarrhea lack of appetite skin irritation
🌿 Toxic Parts:
berries leaves
⚡ Toxic If:

if eaten

Prevent cats from accessing the plant; seek veterinary advice if ingestion occurs or symptoms develop.
Dogs
Slightly Toxic

In dogs, ingestion of Hypericum olympicum can lead to mild gastrointestinal distress and potential photosensitivity. The toxic compounds primarily affect the digestive system and skin.

⚠️ Symptoms:
vomiting diarrhea lethargy skin redness or irritation
🌿 Toxic Parts:
berries leaves
⚡ Toxic If:

if eaten

Keep plants out of reach of pets; monitor for symptoms if ingestion is suspected and consult a veterinarian.
Humans
Slightly Toxic

Hypericum olympicum contains hypericin and other compounds that can cause mild gastrointestinal upset and photosensitivity when ingested. The physiological impact is generally limited to mild irritation and discomfort.

⚠️ Symptoms:
nausea vomiting diarrhea skin irritation upon sun exposure
🌿 Toxic Parts:
berries leaves
⚡ Toxic If:

if eaten

Avoid ingestion; wear protective clothing when handling to prevent skin contact with plant sap, especially in sunlight.
Important: Keep this plant out of reach of children and pets. If ingestion occurs, contact poison control or veterinary services immediately.

Frequently Asked Questions

Q: Is Hypericum olympicum toxic to pets?

A: It is mildly toxic to dogs and cats if ingested.

Q: How often should Hypericum olympicum be watered?

A: Water moderately, allowing the soil to dry slightly between waterings.

Q: Does Hypericum olympicum attract wildlife?

A: Yes, it attracts bees, butterflies, and birds due to its nectar-rich flowers.

Quick Reference
Family: Hypericaceae
Care: easy
Light: full sun to partial shade
Water: every 7–10 days during activ
Suitable For: ["beginners","outdoor landscapers","wildlife supporters (attracts bees, butterflies, birds)"]
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