Black-Eyed Susan vs Night Blooming Cereus Plant Comparison
Compare these two plants side by side — care needs, key differences, and which is right for your home.
Black-Eyed Susan
Rudbeckia hirta
Rudbeckia hirta, commonly known as Black-Eyed Susan, is a flowering plant typically grown as an annual or short-lived perennial. It features daisy-like flowers with bright yellow petals surrounding a dark brown or black central cone. The plant grows upright, reaching heights of 1 to 3 feet. It is primarily an outdoor plant, valued for its vibrant blooms and ability to attract pollinators to gardens. While technically possible to grow indoors, it requires very specific and intense lighting conditions to thrive and bloom, making it challenging.
Night Blooming Cereus
Selenicereus grandiflorus
Selenicereus grandiflorus, commonly known as Night Blooming Cereus, is an epiphytic or lithophytic cactus characterized by its long, sprawling, and often climbing stems. These stems are typically green to grayish-green, ribbed, and may have aerial roots. It is primarily grown for its spectacular, large, white, and highly fragrant flowers that bloom only at night and wither by dawn. This plant is naturally an outdoor plant, thriving in tropical and subtropical climates. People cultivate it for its unique nocturnal blooms and sweet vanilla-like fragrance.
Quick Plant Comparison
| Feature | Black-Eyed Susan | Night Blooming Cereus |
|---|---|---|
| Light | Full sun (at least 6-8 hours of direct sunlight daily) | Bright indirect light to full sun. Requires several hours of direct sunlight for optimal growth and flowering. |
| Watering | Outdoors: Every 3-7 days depending on weather. Indoors (not recommended): Possibly more frequent, but monitor soil moisture carefully. | Every 1-2 weeks during the growing season, less frequently in winter. |
| Humidity | 30-50% | 40-60% |
| Temperature | 18-27°C | 18-27°C |
| Care Level | Expert | Expert |
| Growth Rate | Moderate | Moderate |
| Max Height | Outdoors: 30-90 cm. Indoors (unlikely): Significantly smaller, if it survives. | Up to 3 meters (indoors, if supported), much larger outdoors. |
| Pet Safety | ❌ Toxic To Pets | ❌ Toxic To Pets |
| Soil | Well-draining soil, such as a mix of potting soil, perlite, and sand. | Well-draining cactus mix or a mix of potting soil, perlite, and sand. |
| Beginner Friendly | ❌ No | ❌ No |
| Weekly Maintenance | 5-10 minutes weekly (deadheading) | 30 minutes weekly (including watering, fertilizing, and pest checks). |
🔬 Botanical Information — Comparing These Plants
Black-Eyed Susan
| Scientific Name | Rudbeckia hirta |
|---|---|
| Family | Asteraceae |
| Native To | Eastern and Central North America |
| Also Known As | Black-Eyed Susan, Brown-Eyed Susan, Gloriosa Daisy |
| Leaves | The leaves are lance-shaped, rough in texture, and medium green in color. They are typically 2-6 inches long and arranged alternately along the stem. |
| Flowers | Flowers are daisy-like with bright yellow petals surrounding a dark brown or black central cone. They bloom profusely throughout the summer and into the fall. |
Night Blooming Cereus
| Scientific Name | Selenicereus grandiflorus |
|---|---|
| Family | Cactaceae |
| Native To | Native to the West Indies, Mexico, and Central America |
| Also Known As | Queen of the Night, Large-flowered Cactus, Sweet-scented Cactus, Vanilla Cactus |
| Leaves | The plant does not have true leaves; instead, it has green to grayish-green, ribbed stems that function as photosynthetic organs. The stems are typically 2-3 cm in diameter and have small areoles with spines. |
| Flowers | The flowers are large, white, and highly fragrant, typically 20-30 cm in diameter. They bloom only at night and wither by dawn. Flowering indoors is rare and requires optimal conditions. |
📏 Size & Growth — Plant Comparison
Black-Eyed Susan
Night Blooming Cereus
🌱 Propagation — Comparing Plant Growth
Black-Eyed Susan
Methods: Seed, Division
Difficulty: Easy
Tips: For seeds, sow directly into the garden in spring or start indoors 6-8 weeks before the last frost. For division, divide clumps in early spring or fall.
Night Blooming Cereus
Methods: Stem cuttings, Seed
Difficulty: Easy
Tips: Allow stem cuttings to callous over for a few days before planting in well-draining soil. Keep the soil lightly moist until roots develop.
✨ Benefits & Features — Comparing Plant Value
Black-Eyed Susan
The dark central cone provides a striking contrast to the bright yellow petals. It's a popular choice for attracting pollinators and is relatively deer-resistant.
- ✓ Attracts pollinators
- ✓ Adds vibrant color to gardens
- ✓ Deer resistant
- ✓ Relatively low maintenance outdoors
- ✓ Native plant supports local ecosystems
- ⚠️ Toxic to pets
Night Blooming Cereus
The ephemeral nature of its blooms, opening only for one night, makes it a highly prized and sought-after plant. Its sweet vanilla-like fragrance is also a distinctive characteristic. The plant's epiphytic nature allows it to grow on other plants or rocks in its natural habitat.
- ✓ Unique and dramatic blooms provide a visual spectacle.
- ✓ Sweet fragrance enhances the ambiance of the space, even if briefly.
- ✓ Offers a sense of accomplishment for experienced gardeners.
- ✓ Provides an interesting conversation starter for guests.
- ✓ Can be propagated to create more plants or share with others.
- ⚠️ Toxic to pets
📅 Maintenance Schedule — Plant Care Comparison
Black-Eyed Susan
Night Blooming Cereus
🌞 Light Requirements
Black-Eyed Susan
Full sun (at least 6-8 hours of direct sunlight daily)
Low light tolerant: ❌ No
Night Blooming Cereus
Bright indirect light to full sun. Requires several hours of direct sunlight for optimal growth and flowering.
Low light tolerant: ❌ No
💧 Watering Needs
Black-Eyed Susan
Water thoroughly when the top inch of soil feels dry to the touch. Avoid overwatering, which can lead to root rot. Allow excess water to drain away. Signs of underwatering include wilting leaves; overwatering includes yellowing leaves and soggy soil.
Night Blooming Cereus
Water thoroughly when the top inch of soil is dry. Reduce watering during the dormant winter months. Overwatering can lead to root rot, indicated by yellowing and mushy stems. Underwatering results in shriveled stems and lack of flowering.
🌡️ Temperature & Humidity
Black-Eyed Susan
Temperature: 18-27°C
Humidity: 30-50%
Night Blooming Cereus
Temperature: 18-27°C
Humidity: 40-60%
🤔 Which Plant Is Right For You?
Black-Eyed Susan
Rudbeckia hirtaGardeners looking to add vibrant color and attract pollinators to their outdoor spaces.
✅ Choose This Plant If...
- You want to attract pollinators to your garden.
- You desire a long-blooming, cheerful flower.
- You need a deer-resistant plant.
- You want a low-maintenance outdoor plant once established.
- You want a native North American wildflower.
❌ Skip This Plant If...
- You have limited sunlight indoors.
- You have pets that might ingest the plant.
- You are looking for a low-maintenance INDOOR plant.
Night Blooming Cereus
Selenicereus grandiflorusExperienced plant enthusiasts who can provide the necessary light and space for this plant to thrive, ideally in a greenhouse or outdoor setting.
✅ Choose This Plant If...
- You want a plant with dramatic, fragrant blooms, even if only for one night.
- You have a greenhouse or sunny outdoor space where it can thrive.
- You are an experienced gardener who enjoys a challenge.
- You are fascinated by nocturnal plants and their unique adaptations.
- You want to propagate and share cuttings with friends.
❌ Skip This Plant If...
- You have limited space indoors.
- You cannot provide very bright light.
- You have pets that might ingest the plant.
- You are a beginner gardener.
- You want a plant that flowers frequently and for extended periods.
🎯 Quick Verdict
⚡ 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
Black-Eyed Susan Care Tips
Black-Eyed Susans are primarily outdoor plants that require full sun and well-draining soil. Growing them indoors is extremely challenging due to their high light requirements. They are toxic to pets. Indoor survival is unlikely without specialized grow lights and careful monitoring.
- Provide full sun for optimal blooming.
- Ensure well-draining soil to prevent root rot.
- Deadhead spent flowers regularly.
- Water deeply but infrequently.
- Monitor for pests and diseases.
Night Blooming Cereus Care Tips
Night Blooming Cereus is primarily an outdoor plant that can be challenging to grow indoors due to its high light requirements and sprawling growth habit. It needs very bright light, well-draining soil, and careful watering to thrive. Flowering indoors is rare without optimal conditions. It is also toxic to pets.
- Provide a trellis or support structure for the stems to climb.
- Ensure excellent drainage to prevent root rot.
- Water deeply but infrequently, allowing the soil to dry out between waterings.
- Fertilize regularly during the growing season to promote flowering.
- Provide a period of cooler temperatures in winter to encourage flower bud formation.
⚠️ Common Problems & Solutions — Plant Care Comparison
Black-Eyed Susan
Night Blooming Cereus
❓ Frequently Asked Questions — Comparing These Plants
Black-Eyed Susan
What are the light requirements for Black-Eyed Susan?
Black-Eyed Susans are sun-loving plants and require at least 6 hours of direct sunlight each day to thrive. Insufficient light can lead to leggy growth, reduced blooming, and pale foliage. When grown indoors, place them near a south-facing window where they can receive ample sunlight. If natural light is limited, supplement with grow lights to ensure they get the light they need.
How do I care for Black-Eyed Susan?
Black-Eyed Susans thrive in full sun, requiring at least 6 hours of direct sunlight daily. Well-draining soil is crucial to prevent root rot; amend heavy clay soils with compost or sand. Water regularly, especially during dry periods, but avoid overwatering. Fertilize sparingly with a balanced fertilizer in the spring to encourage blooming. Deadhead spent flowers to promote continuous blooming throughout the season.
How do I propagate Black-Eyed Susan?
Black-Eyed Susans can be propagated through division or seeds.
Night Blooming Cereus
What are the light requirements for Night Blooming Cereus?
Night Blooming Cereus thrives in bright, indirect light. Direct sunlight can scorch the stems, especially during the hottest part of the day. An east-facing window is often ideal, providing gentle morning sun. A west-facing window can also work, but be sure to provide some shade during the afternoon.
How do I care for Night Blooming Cereus?
Night Blooming Cereus requires bright, indirect light, especially during the growing season. Water sparingly, allowing the soil to dry out completely between waterings. Overwatering is a common cause of problems. Use a well-draining cactus mix and a pot with drainage holes. Fertilize lightly during the growing season (spring and summer) with a balanced cactus fertilizer.
How do I propagate Night Blooming Cereus?
Night Blooming Cereus can be propagated through offsets, seeds, or grafting. Offsets are the easiest method. Simply detach a healthy offset from the main plant and allow the cut end to callus over for a few days. Then, plant the offset in well-draining cactus mix and water sparingly until roots develop.
Last updated: May 9, 2026 — Plant care data reviewed and verified by our editorial team.