Annual Mercury
mercurialis annua
Also known as: ["French Mercury","Spurge Mercury"]
Overview
A fast-growing annual herbaceous plant with simple, alternate leaves and inconspicuous greenish flowers.
Benefits & Perks
["fast growing","drought tolerant"]
Botanical Classification
| Phylum: | Magnoliophyta |
| Class: | Magnoliopsida |
| Order: | Malpighiales |
| Family: | Euphorbiaceae |
| Genus: | Mercurialis |
| Botanical Name: | Mercurialis annua |
Plant Characteristics
Basic Information
- Category: Herbs & Weeds
- Suitable Location: outdoor garden bed or container
- Suitable For:
- Is Weed: No
- Allergenicity: low
Environmental Needs
- Climate: {"temperatureRange":"10–30°C"}
- Hardiness: {"zones":"8–11"}
- Misting: rarely required
- Drainage: Fast-draining to prevent waterlogging.
- Soil Type: Well-draining, loamy soil with some organic matter. A standard potting mix with added perlite or sand works well.
Maintenance Level
- Maintenance Level: very low
- Toughness Level: very high
- Pruning Frequency: As needed, but light pruning can be done every 4–6 weeks during active growth.
- Pruning Intensity: Light to moderate. Avoid heavy pruning unless necessary to control size or shape.
Care Details
Ideal Sunlight Coverage:
Full sun to partial shade (4–6 hours of direct sunlight daily). Tolerates light shade but may become leggy.
Sunlight Tolerance Tips:
Acclimate plants gradually to direct sunlight to avoid scorching. Place in a spot with morning sun and afternoon shade if in a hot climate. Indoors, place near a south-facing window with filtered light.
Care Requirements
Care Difficulty
very easyeasy
Sunlight
full sun to partial shade
Rotate plant for even growth; avoid intense midday sun; adjust for seasonal light changes.
Watering
every 7–10 days during active growth, reduce in winter
Water thoroughly but infrequently; ensure proper drainage; adjust frequency based on season and growth stage.
Soil
well-draining, moderately fertile soil
pH: Slightly acidic to neutral (pH 6.0–7.0).
Ensure good drainage; avoid heavy clay soils; amend with organic matter for fertility.
Temperature
Prefers warm conditions (65–85°F or 18–29°C). Tolerates mild frosts but grows best in moderate warmth.
Protect from frost; avoid sudden temperature changes; maintain moderate warmth for optimal growth.
Fertilizing
every 4–6 weeks during growing season
Fertilize only when actively growing; avoid over-fertilizing to prevent salt buildup; flush soil occasionally to remove excess salts.
Propagation
Methods
Stem cuttings or seed. Stem cuttings are the most common and reliable method for home growers.
Step-by-Step Propagation Guide
- Take a 4–6 inch cutting just below a leaf node.
- Remove lower leaves.
- Dip in rooting hormone (optional).
- Plant in moist propagation medium.
- Keep humid and warm.
Best Time: Spring or early summer when the plant is actively growing.
Environment
Warm, humid environment with indirect light. Maintain temperatures around 70–75°F (21–24°C).
Medium
Well-draining potting mix, such as a mix of peat and perlite or cactus mix.
Hormone
Optional but recommended for faster rooting.
Timeline
Roots typically form within 2–4 weeks. Plants can be transplanted after 6–8 weeks.
Tools Needed
Pruning shears, rooting hormone, small pots, well-draining soil mix, plastic wrap or propagator.
Quick Tips
Use healthy, non-flowering stems; keep consistently moist; provide bottom heat if possible.
Pruning & Repotting
Pruning Guide
Method
Pinch back tips to encourage branching. Trim back leggy stems to promote fuller growth.
Pruning Plan
Prune to maintain shape, encourage bushier growth, and remove dead or diseased foliage. Light pruning can be done throughout the growing season.
Tools
Pruning shears, sharp scissors, or your fingers for pinching.
Checklist
Use clean tools; prune dead or damaged growth; shape as desired; dispose of clippings properly.
Repotting Guide
Best Season
Spring, before the active growing season begins.
Pot Size
Choose a pot one size larger (1–2 inches wider in diameter) than the current one.
Method
Gently remove the plant from its pot, trim any circling roots, place in a new pot with fresh soil, and water lightly.
Suggestions
Repot every 1–2 years or when the plant becomes root-bound. Young plants may need repotting more frequently.
Checklist
Check root boundness; prepare new pot with drainage; trim roots if needed; use fresh soil; water after repotting.
Advanced Care Tips
Watering Mastery
Watering Checklist
Check soil moisture; water at root zone; ensure drainage; adjust for season.
How to Apply Water Properly
Water directly at the root zone until the soil is evenly moist but not waterlogged. Ensure excess water drains away to prevent root rot. Water early in the morning to minimize evaporation.
Watering Schedule Tips
Water lightly and frequently during active growth in spring and summer, allowing soil to dry slightly between waterings. Reduce watering in fall and winter to prevent root rot.
Soil Improvement
Add perlite or coarse sand to improve drainage; incorporate compost for fertility; ensure good aeration by avoiding compacted soil.
Temperature Stress Management
Signs of Temperature Issues
Wilting, yellowing leaves, or stunted growth in extreme heat or cold. Bud drop or leaf drop in sudden temperature fluctuations.
Cold Stress
Slows growth and may cause leaf discoloration or dieback in prolonged cold. Can survive light frosts but prolonged freezing is detrimental.
Solution: Move potted plants indoors or to a sheltered location during cold spells. Apply a layer of mulch to protect roots in-ground.
Hot Stress
Leaves may wilt, curl, or develop brown edges in excessive heat. Growth may slow, and flowering may be reduced.
Solution: Provide shade during peak heat, increase watering frequency, and ensure good air circulation to mitigate heat stress.
Fertilizing Guide
Fertilizing Checklist
Check growth stage; use diluted fertilizer; avoid winter feeding; flush soil periodically.
Fertilizing Method
Use a balanced, water-soluble fertilizer diluted to half strength every 4–6 weeks during the growing season (spring and summer). Avoid fertilizing in fall and winter.
Common Problems & Solutions
Toxicity Warning
Cats
Non-toxicMercurialis annua is not considered toxic to cats. Ingestion of the plant is unlikely to cause adverse effects in felines.
🌿 Toxic Parts:
⚡ Toxic If:
if eaten
Dogs
Non-toxicMercurialis annua is not considered toxic to dogs. Ingestion of the plant is unlikely to cause adverse effects in canines.
🌿 Toxic Parts:
⚡ Toxic If:
if eaten
Humans
Non-toxicMercurialis annua, commonly known as annual mercury, is generally considered non-toxic to humans. There are no significant toxic effects or physiological impacts reported from ingestion.
🌿 Toxic Parts:
⚡ Toxic If:
if eaten
Frequently Asked Questions
Q: Is Mercurialis annua toxic to pets?
A: Reliable information on toxicity to pets is not available.
Q: How does this plant spread?
A: It spreads via seeds and can be invasive in some regions.
Q: Is it suitable for ornamental use?
A: Generally not, as it is considered a weed.
Quick Reference
| Family: | Euphorbiaceae |
| Care: | very easy |
| Light: | full sun to partial shade |
| Water: | every 7–10 days during activ |
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