St. John's Wort Spurge

euphorbia hypericifolia

Also known as: ["Hypericifolia spurge","St. John's Wort Leaf Spurge"]

Family: Euphorbiaceae Genus: Euphorbia Category: Flowers

Overview

A herbaceous annual plant with small, star-shaped yellow flowers and narrow, linear leaves resembling those of St. John's Wort.

Benefits & Perks

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

Botanical Classification

Phylum: Magnoliophyta
Class: Magnoliopsida
Order: Malpighiales
Family: Euphorbiaceae
Genus: Euphorbia
Botanical Name: Euphorbia hypericifolia

Plant Characteristics

Basic Information
  • Category: Flowers
  • Suitable Location: outdoor garden bed in a sunny location, or as a container plant in a bright spot
  • Suitable For:
    Busy People (low Maintenance) Outdoor Landscapers Wildlife Supporters
  • Is Weed: No
  • Allergenicity: low
Environmental Needs
  • Climate: {"temperatureRange":"10–35°C"}
  • Hardiness: {"zones":"9–11"}
  • Misting: rarely required, only if ambient humidity is very low
  • Drainage: Fast-draining
  • Soil Type: Well-draining potting mix with added perlite or sand
Maintenance Level
  • Maintenance Level: low
  • Toughness Level: moderate
  • Pruning Frequency: As needed, typically every 2–3 months or after flowering
  • Pruning Intensity: Light to moderate
Care Details

Ideal Sunlight Coverage:
Bright indirect light for 6–8 hours daily; tolerates partial shade.

Sunlight Tolerance Tips:
Acclimate gradually to intense light; protect from direct midday sun to avoid scorching; adjust placement based on indoor/outdoor conditions.

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

Care Requirements

Care Difficulty
easy

easy

Sunlight

full sun to partial shade

Rotate plant for even light exposure; use sheer curtains to filter intense sunlight; avoid drafty windows.

Watering

every 7–10 days, allowing soil to dry between waterings

Allow soil to dry between waterings; avoid overwatering; water early in the day.

Soil

well-draining, sandy or loamy soil

pH: 6.0–7.5 (slightly acidic to neutral)

Use a pot with drainage holes; avoid heavy clay soils; top-dress with compost annually.

Temperature

Prefers 65–80°F (18–27°C); tolerates mild fluctuations but avoid extreme cold or heat.

Avoid placing near heating/cooling vents; use a thermometer to monitor ambient temperature; adjust care based on seasonal changes.

Fertilizing

every 4–6 weeks during active growing season (spring and summer)

Flush soil occasionally to prevent salt buildup; apply fertilizer to moist soil to avoid root burn.

Propagation

Methods

Stem cuttings

Step-by-Step Propagation Guide
  1. Take a 4–6 inch cutting, let it callus for a day, plant in medium, keep moist, provide warmth and humidity.

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

Environment

High humidity (70–80%), warm (70–75°F), indirect light

Medium

Well-draining mix of perlite and peat moss

Hormone

Optional, but recommended for faster rooting

Timeline

Roots in 2–4 weeks; establish in 6–8 weeks

Tools Needed

Pruning shears, rooting hormone, small pot, perlite, peat moss

Quick Tips

Use sterile tools to prevent disease; maintain consistent moisture; avoid direct sunlight during rooting.

Pruning & Repotting

Pruning Guide
Method

Pinch back tips or cut stems just above a leaf node

Pruning Plan

Remove dead or leggy stems to encourage bushier growth; shape as needed.

Tools

Pruning shears, gloves

Checklist

Sterilize tools, wear gloves, cut at an angle, dispose of clippings properly.

Repotting Guide
Best Season

Spring, before active growth begins

Pot Size

One size larger pot; ensure it has drainage holes

Method

Remove plant gently, trim roots if necessary, place in new pot with fresh soil, water lightly

Suggestions

Repot every 2–3 years or when roots fill the pot; beneficial for growth and soil refresh.

Checklist

Check root bound status, prepare new pot, trim roots, use fresh soil, water lightly after repotting.

Advanced Care Tips

Watering Mastery
Watering Checklist

Check soil moisture, water deeply, ensure drainage, avoid wetting foliage.

How to Apply Water Properly

Water deeply at the root zone until water drains from the bottom; ensure excess water drains away to prevent waterlogging.

Pro Tip: Use a watering can with a narrow spout to direct water to the base of the plant.
Watering Schedule Tips

Water thoroughly when the top inch of soil is dry; reduce frequency in winter to prevent root rot.

Soil Improvement

Add perlite or coarse sand to improve drainage; incorporate organic matter for fertility.

Temperature Stress Management
Signs of Temperature Issues

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

Cold Stress

Slows growth, may cause leaf discoloration or dieback in temperatures below 50°F (10°C).

Solution: Move to a warmer location; protect from drafts; use a space heater if necessary.

Hot Stress

Leaves may wilt, curl, or develop brown edges in temperatures above 90°F (32°C).

Solution: Provide shade; increase humidity with misting; ensure adequate ventilation.

Fertilizing Guide
Fertilizing Checklist

Check season, dilute fertilizer, water before application, avoid contact with foliage.

Fertilizing Method

Use a balanced liquid fertilizer diluted to half strength every 4–6 weeks during growing season (spring/summer); avoid fertilizing in winter.

Common Problems & Solutions

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

Wilting in Euphorbia hypericifolia can result from water stress, either due to overwatering causing root rot or underwatering leading to dehydration, both of which impair nutrient uptake and plant stability.

Leaf spots on Euphorbia hypericifolia may be caused by fungal or bacterial pathogens, resulting in reduced photosynthetic area and potential defoliation if the infection spreads.

Rotting, particularly root or stem rot, can occur in Euphorbia hypericifolia due to excessive moisture or fungal infections, leading to decay of plant tissues and potential plant death.

Toxicity Warning

Cats
Toxic

Cats are susceptible to toxicity from Euphorbia hypericifolia, particularly if they ingest any part of the plant. The latex is highly irritating and can cause severe gastrointestinal and dermal reactions.

⚠️ Symptoms:
vomiting diarrhea drooling lethargy loss of appetite
🌿 Toxic Parts:
latex leaves stems
⚡ Toxic If:

if ingested

Prevent cats from accessing the plant. If ingestion is suspected, seek veterinary care promptly. Monitor the cat for any signs of distress and keep the plant out of reach.
Dogs
Toxic

Ingestion of Euphorbia hypericifolia by dogs can cause significant gastrointestinal upset due to the irritant properties of the latex and other compounds. The plant can also cause skin irritation upon contact.

⚠️ Symptoms:
vomiting diarrhea drooling abdominal pain lethargy
🌿 Toxic Parts:
latex leaves stems
⚡ Toxic If:

if ingested

Keep pets away from the plant. If ingestion is suspected, contact a veterinarian immediately. Do not induce vomiting without professional guidance.
Humans
Toxic

Euphorbia hypericifolia contains toxic latex that can cause severe irritation upon contact with skin or mucous membranes. Ingestion can lead to gastrointestinal distress and systemic effects due to the presence of diterpene esters and other irritant compounds.

⚠️ Symptoms:
skin irritation burning sensation eye irritation vomiting diarrhea abdominal pain
🌿 Toxic Parts:
latex leaves stems
⚡ Toxic If:

if touched or ingested

Avoid contact with the latex. Wear gloves when handling. In case of contact, wash thoroughly with soap and water. Seek medical attention if ingested or if irritation persists.
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 Euphorbia hypericifolia toxic to pets?

A: Yes, it is mildly toxic to dogs and cats if ingested.

Q: How often should I water Euphorbia hypericifolia?

A: Water sparingly, as it is drought tolerant and prefers well-drained soil.

Q: Does this plant attract wildlife?

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

Quick Reference
Family: Euphorbiaceae
Care: easy
Light: full sun to partial shade
Water: every 7–10 days, allowing so
Suitable For: ["busy people (low maintenance)","outdoor landscapers","wildlife supporters (attracts bees, butterflies, birds)"]
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