Four O'Clock vs Silver Dollar Plant Plant Comparison

Compare these two plants side by side — care needs, key differences, and which is right for your home.

Four O'Clock

Four O'Clock

Mirabilis jalapa

VS
Silver Dollar Plant

Silver Dollar Plant

Lunaria annua

Four O'Clock

Four O'Clock

Mirabilis jalapa

Mirabilis jalapa, commonly known as the Four O'Clock flower, is a bushy, herbaceous perennial typically grown as an annual in cooler climates. It's known for its trumpet-shaped flowers that open in the late afternoon or early evening, releasing a sweet fragrance. The flowers come in a variety of colors, including pink, red, yellow, white, and multicolored variations. It grows from tuberous roots and can reach a height of 1-3 feet. It is primarily grown outdoors in gardens and borders for its vibrant colors and evening fragrance. It is not ideally suited as an indoor plant.

Nyctaginaceae Tropical South America
✨ Features: Flowers open in the late afternoon or early evening and emit a sweet fragrance; flowers come in a variety of colors and can even be multicolored on the same plant.
📖 Read Complete Four O'Clock Guide
Silver Dollar Plant

Silver Dollar Plant

Lunaria annua

Lunaria annua, commonly known as the Silver Dollar Plant, is a biennial plant grown for its distinctive, translucent seedpods that resemble silver coins. It typically reaches a height of 60-90 cm. In the first year, it develops foliage, and in the second year, it produces fragrant, purple or white flowers in spring, followed by the iconic flattened seedpods. While sometimes grown indoors, it is primarily an outdoor plant, often used in dried flower arrangements. People grow it for its unique ornamental value and the beauty of its dried seedpods.

Brassicaceae Southeastern Europe and Western Asia
✨ Features: Attractive seedpods, fragrant flowers, used in dried flower arrangements.
📖 Read Complete Silver Dollar Plant Guide

Quick Plant Comparison

Feature Four O'Clock Silver Dollar Plant
Light Full sun to partial shade Full sun to partial shade outdoors. Indoors, requires very bright, direct light for several hours daily.
Watering Every 3-7 days depending on weather and soil drainage Outdoors: Every 5-7 days during growing season. Indoors: Every 7-10 days, adjust based on light and temperature.
Humidity 40-60% 30-50%
Temperature 18-27°C 15-24°C
Care Level Expert Expert
Growth Rate Fast Fast
Max Height 0.3-1 meter (indoors unlikely to reach this height) Outdoors: 60-90 cm. Indoors: 30-60 cm (smaller due to limited space and light).
Pet Safety ❌ Toxic To Pets ❌ Mildly Toxic
Soil Well-draining soil, such as a mix of garden soil, sand, and compost Well-draining garden soil or potting mix.
Beginner Friendly ❌ No ❌ No
Weekly Maintenance 15 minutes weekly 15 minutes weekly

🔬 Botanical Information — Comparing These Plants

Four O'Clock

Scientific Name Mirabilis jalapa
Family Nyctaginaceae
Native To Tropical South America
Also Known As Four O'Clock Flower, Marvel of Peru, Beauty-of-the-Night
Leaves The leaves are ovate to lance-shaped, typically 2-4 inches long, and have a smooth texture. They are usually medium green in color and arranged oppositely along the stems.
Flowers Flowers are trumpet-shaped, about 1-2 inches long, and come in a variety of colors including pink, red, yellow, white, and multicolored. They open in the late afternoon or early evening and emit a sweet fragrance. Flowering indoors is rare and unlikely.

Silver Dollar Plant

Scientific Name Lunaria annua
Family Brassicaceae
Native To Southeastern Europe and Western Asia
Also Known As Silver Dollar Plant, Honesty, Money Plant, Moonwort, Penny Flower
Leaves The leaves are ovate to heart-shaped, with toothed edges. They are typically green and can be slightly hairy.
Flowers It produces fragrant, four-petaled flowers in spring, typically purple or white. Flowers are followed by the development of the seedpods.

📏 Size & Growth — Plant Comparison

Four O'Clock

Height 0.3-1 meter (indoors unlikely to reach this height)
Spread 0.3-0.6 meters (can spread via tuberous roots)
Growth Rate Fast
Growth Pattern Bushy and upright, typically reaching 1-3 feet in height and spread. It grows from tuberous roots, which allow it to regrow each year in warmer climates.

Silver Dollar Plant

Height Outdoors: 60-90 cm. Indoors: 30-60 cm (smaller due to limited space and light).
Spread 30-45 cm
Growth Rate Fast
Growth Pattern Upright, branching biennial. In the first year, it forms a rosette of basal leaves. In the second year, it sends up a flowering stalk.

🌱 Propagation — Comparing Plant Growth

Four O'Clock

Methods: Seed, Tuber division

Difficulty: Easy

Tips: Sow seeds directly in the garden after the last frost or start them indoors 6-8 weeks before. Divide tubers in early spring.

Silver Dollar Plant

Methods: Seed

Difficulty: Easy

Tips: Sow seeds directly into the garden in spring or fall. For indoor propagation, start seeds indoors 6-8 weeks before the last frost. Keep soil consistently moist until germination.

✨ Benefits & Features — Comparing Plant Value

Four O'Clock

The flowers open in the late afternoon or early evening, hence the name 'Four O'Clock'. They are known for their sweet fragrance and the ability to produce multiple colors on the same plant, sometimes even on the same flower.

  • ✓ Adds vibrant color to the garden
  • ✓ Provides a sweet evening fragrance
  • ✓ Attracts pollinators
  • ✓ Relatively low-maintenance once established
  • ✓ Can self-seed and naturalize in suitable climates
  • ⚠️ Toxic to pets

Silver Dollar Plant

The most distinctive feature is its translucent, silvery seedpods, which are revealed after the outer layers of the pod dry and fall off. These pods are popular for dried flower arrangements and add a unique textural element to gardens.

  • ✓ Aesthetic appeal with unique seedpods.
  • ✓ Fragrant flowers in spring.
  • ✓ Attracts pollinators to the garden.
  • ✓ Provides material for dried flower arrangements.
  • ✓ Adds visual interest to the garden throughout the year.
  • ⚠️ Toxic to pets

📅 Maintenance Schedule — Plant Care Comparison

Four O'Clock

Repotting Not typically grown indoors. If grown in containers, repot annually in the spring, especially if root-bound.
Pruning Deadhead spent flowers to encourage more blooms. Prune back stems in late fall to prepare for winter dormancy.
Fertilizing Balanced liquid fertilizer (10-10-10) diluted to half strength, every 4-6 weeks during the growing season
Seasonal Care In colder climates, treat as an annual or dig up tubers in the fall and store them in a cool, dry place for replanting in the spring. Reduce watering in the winter.

Silver Dollar Plant

Repotting Not typically repotted if grown outdoors. If grown indoors, repot annually in spring.
Pruning Prune spent flower stalks to encourage seedpod development. Remove any dead or diseased foliage.
Fertilizing Balanced liquid fertilizer diluted to half strength, applied monthly during the growing season (spring and summer).
Seasonal Care Spring/Summer: Regular watering and fertilization. Fall: Allow seedpods to dry on the plant. Winter: Dormancy; reduce watering.

🌞 Light Requirements

Four O'Clock

Full sun to partial shade

Low light tolerant: ❌ No

Silver Dollar Plant

Full sun to partial shade outdoors. Indoors, requires very bright, direct light for several hours daily.

Low light tolerant: ❌ No

💧 Watering Needs

Four O'Clock

Water deeply when the top inch of soil feels dry. Avoid overwatering, which can lead to root rot. During hot summer months, more frequent watering may be necessary. Reduce watering in cooler months.

Silver Dollar Plant

Outdoors, water regularly, allowing the soil to dry slightly between waterings. Indoors, water thoroughly when the top inch of soil is dry. Overwatering can lead to root rot. Underwatering will cause leaves to wilt and dry.

🌡️ Temperature & Humidity

Four O'Clock

Temperature: 18-27°C

Humidity: 40-60%

Silver Dollar Plant

Temperature: 15-24°C

Humidity: 30-50%

🤔 Which Plant Is Right For You?

Four O'Clock

Four O'Clock

Mirabilis jalapa
Care: Expert Time: 15 minutes weekly Beginner: No

Gardeners looking for a fragrant, colorful addition to their evening garden.

✅ Choose This Plant If...

  • You want a fragrant evening garden
  • You enjoy vibrant, multicolored flowers
  • You want a plant that attracts pollinators like moths and hummingbirds
  • You are looking for a low-maintenance outdoor plant once established
  • You want a plant that can self-seed and return year after year.

❌ Skip This Plant If...

  • You have pets that may ingest the plant
  • You lack a sunny outdoor space
  • You want a plant that thrives indoors.
📍 Ideal Location: Outdoor garden, sunny border, or patio container
🎨 Style: Cottage, Bohemian, Traditional
🏠 Apartment Friendly: No
⚠️ All parts of the plant, especially the seeds and roots, are toxic to dogs, cats, and horses. Symptoms include vomiting, diarrhea, and abdominal pain. According to the ASPCA, it contains asparagine.
Silver Dollar Plant

Silver Dollar Plant

Lunaria annua
Care: Expert Time: 15 minutes weekly Beginner: No

Gardeners who want a unique ornamental plant for dried flower arrangements and have a sunny outdoor space.

✅ Choose This Plant If...

  • You want a unique plant for dried flower arrangements.
  • You have a sunny outdoor garden space.
  • You appreciate the silvery seedpods.
  • You enjoy fragrant flowers in the spring.
  • You are experienced with gardening and can provide the specific care this plant needs.

❌ Skip This Plant If...

  • You have limited sunlight indoors.
  • You are a beginner gardener.
  • You have pets that might ingest the seeds.
  • You don't have an outdoor garden space.
📍 Ideal Location: Sunny garden bed or border. Indoors: South-facing window.
🎨 Style: Cottage, Rustic, Bohemian
🏠 Apartment Friendly: Limited
⚠️ The seeds contain saponins, which can cause mild gastrointestinal upset if ingested by humans or pets. Symptoms may include nausea, vomiting, and diarrhea. Contact with the sap may cause skin irritation in sensitive individuals.

🎯 Quick Verdict

Best for Beginners Neither ideal
Pet Friendly Neither - caution
Less Maintenance Similar effort
Apartment Friendly Check space

⚡ Key Differences Between These Plants

🌿

Both plants have similar basic care requirements but differ in appearance and specific needs. Compare plants carefully to find the best fit for your space.

💡 Pro Tips For Comparing These Plants

Four O'Clock Care Tips

Four O'Clocks are primarily outdoor plants and require full sun to thrive. Growing them indoors is challenging due to their high light requirements and potential for pest infestations. They also spread via tuberous roots, which can quickly outgrow a container. Indoor flowering is unlikely.

  • Plant in well-draining soil to prevent root rot.
  • Provide full sun for best flowering.
  • Deadhead spent flowers regularly to encourage more blooms.
  • Protect from strong winds, which can damage the delicate stems.
  • Monitor for pests like aphids and treat promptly.
❄️ Winter: In colder climates, dig up the tubers and store them in a cool, dry place over the winter. Alternatively, treat as an annual and replant in the spring.
☀️ Summer: Provide consistent moisture during the hot summer months. Deadhead spent flowers to encourage more blooms. Monitor for pests and diseases.

Silver Dollar Plant Care Tips

Silver Dollar Plant is primarily an outdoor plant and requires very bright light to thrive indoors. It is challenging to grow indoors due to its high light requirements and susceptibility to pests. Requires well-draining soil and careful watering to prevent root rot.

  • Provide well-draining soil to prevent root rot.
  • Ensure at least 6 hours of direct sunlight daily.
  • Fertilize monthly during the growing season.
  • Allow seedpods to dry on the plant before harvesting.
  • Protect from strong winds.
❄️ Winter: Reduce watering during the winter months. Protect from frost in colder climates. Mulch around the base of the plant to insulate the roots.
☀️ Summer: Water regularly during hot, dry periods. Provide afternoon shade in extremely hot climates to prevent leaf scorch.

⚠️ Common Problems & Solutions — Plant Care Comparison

Four O'Clock

Common Issues: Powdery mildew, Aphids, Root rot
Solutions: Powdery mildew: Improve air circulation and apply a fungicide. Aphids: Spray with insecticidal soap. Root rot: Ensure well-draining soil and avoid overwatering.

Silver Dollar Plant

Common Issues: Powdery mildew, aphids, root rot, legginess (due to insufficient light).
Solutions: Powdery mildew: Improve air circulation and apply a fungicide. Aphids: Spray with insecticidal soap. Root rot: Ensure well-draining soil and avoid overwatering. Legginess: Provide more light.

❓ Frequently Asked Questions — Comparing These Plants

Four O'Clock

What are the light requirements for Four O'Clock?

Four O’Clocks thrive in full sun, needing at least 6 hours of direct sunlight daily to produce abundant blooms. A sunny location encourages strong growth and vibrant flower colors. While they can tolerate partial shade, reduced sunlight will result in fewer flowers and leggier growth.

How do I care for Four O'Clock?

Four O’Clocks are relatively easy to care for. Plant them in well-draining soil in a location that receives at least 6 hours of sunlight daily for optimal blooming. Water regularly, especially during dry periods, but avoid overwatering, which can lead to root rot. Fertilize monthly during the growing season with a balanced fertilizer or one formulated for blooming plants to encourage abundant flowering.

How do I propagate Four O'Clock?

Four O’Clocks can be propagated through seeds, tubers, or stem cuttings.

Silver Dollar Plant

What are the light requirements for Silver Dollar Plant?

Silver Dollar Plants thrive in bright, indirect light. A spot near an east- or west-facing window is ideal. They can tolerate some direct morning sun, but avoid harsh afternoon sun, which can scorch their delicate leaves. If your plant is not receiving enough light, it may become leggy and the leaves may lose their vibrant color. Rotate the plant regularly to ensure even growth on all sides. If natural light is insufficient, consider supplementing with a grow light. Insufficient light will cause etiolation, where the stems stretch in search of light.

How do I care for Silver Dollar Plant?

Silver Dollar Plants are relatively easy to care for, making them ideal for beginners. Provide bright, indirect light; direct sunlight can scorch the leaves. Water thoroughly only when the soil is completely dry, typically every 2-4 weeks, depending on the environment. Use well-draining soil, such as a cactus or succulent mix, to prevent root rot. Ensure the pot has drainage holes. Fertilize sparingly, only during the growing season (spring and summer), with a diluted succulent fertilizer. Maintain temperatures between 65-75°F (18-24°C). Avoid overwatering, as this is the most common cause of problems. Prune any dead or yellowing leaves to encourage healthy growth. Repot every 1-2 years, or when the plant becomes root-bound.

How do I propagate Silver Dollar Plant?

Silver Dollar Plants can be easily propagated through leaf cuttings, offsets, or stem cuttings. For leaf cuttings, allow the cut end to callous over for a few days, then place it on well-draining soil. Keep the soil slightly moist until roots develop. Offsets can be carefully separated from the mother plant and planted in their own pots. For stem cuttings, take a 2-3 inch cutting, allow it to callous, and then plant it in well-draining soil. Provide bright, indirect light and water sparingly until the new plant establishes itself. Propagation is best done during the growing season. With proper care, new plants will develop within a few weeks.

Last updated: May 6, 2026 — Plant care data reviewed and verified by our editorial team.