If you’re looking for a plant that delivers pure magic after dark, look no further than Selenicereus grandiflorus. This night-blooming cactus flower is one of nature’s most spectacular, yet fleeting, performances, often called the Queen of the Night.
Its stunning, large white blossoms open only once at night and wilt by dawn. Growing this cactus is a rewarding challenge for patient gardeners who want to witness this extraordinary event. This guide gives you all the practical steps to successfully cultivate and enjoy your own Selenicereus grandiflorus.
Selenicereus Grandiflorus
This cactus is a climber or scrambler in its natural habitat, often found in the Caribbean and parts of Central America. It’s an epiphyte or lithophyte, meaning it grows on trees or rocks, not in soil. Its stems are long, slender, and ribbed, with small aerial roots and sparse spines.
The real prize is the flower. It’s huge, sometimes over a foot across, with numerous narrow, pointed golden-yellow outer petals and broader, pure white inner petals. The fragrance is intensely sweet, designed to attract its nocturnal moth pollinators.
Why It’s Called the Queen of the Night
The name perfectly captures its behavior. The buds swell for days, then open dramatically over just a few evening hours. The bloom is often so brief that you must stay up late to see it in its full glory. Many gardeners host “bloom watch” parties for this special occasion.
Key Characteristics to Recognize
- Stems: Green, creeping or climbing, can reach over 10 feet long.
- Spines: Short, hair-like, and grouped in small clusters along the stems ribs.
- Flowers: Very large, white and yellow, with a prominent cluster of yellow stamens.
- Fragrance: A powerful, sweet, almost vanilla-like scent that fills the night air.
- Fruit: If pollinated, it produces a red, spiny fruit that’s edible but not often seen in cultivation.
Ideal Growing Conditions
To mimic its natural home, you need to provide the right environment. Getting this right is the key to triggering those famous blooms.
Light Requirements
This plant loves bright, indirect light. Some morning or late afternoon sun is fine, but harsh midday sun can scorch its stems. Indoors, an east or west-facing window is ideal. If the stems start to look pale or yellowish, it might be getting to much light.
Temperature & Humidity
It prefers warm temperatures between 70-85°F (21-29°C) during the growing season. It can tolerate cooler temps down to 50°F (10°C) in winter, which is actually beneficial for bud formation. Average household humidity is acceptable, but it appreciates higher humidity, similar to its tropical origins.
Best Soil and Potting Mix
Never use a heavy, water-retentive soil. It needs a very fast-draining, airy mix. A perfect blend for Selenicereus grandiflorus is:
- 1 part regular potting soil
- 1 part coarse perlite or pumice
- 1 part orchid bark or coconut coir chips
Make sure your pot has excellent drainage holes. A shallow, wide pot can work well to accommodate its spreading habit.
Your Step-by-Step Care Guide
Consistent care through the seasons will keep your plant healthy and encourage flowering.
1. How to Water Correctly
Water deeply when the top few inches of the mix are completely dry. During active growth in spring and summer, this may be once a week. Always let excess water drain away—never let the pot sit in a saucer of water. In fall and winter, reduce watering significantly, allowing the mix to dry out almost completely between waterings.
2. Feeding for Growth and Flowers
Feed your cactus with a balanced, water-soluble fertilizer (like a 10-10-10) diluted to half strength. Do this every 4-6 weeks during the spring and summer. In late summer, you can switch to a fertilizer with a higher phosphorus number (the middle number) to support bud development. Stop feeding entirely in fall and winter.
3. Pruning and Support
The long stems need support. You can train them on a trellis, moss pole, or even let them cascade from a hanging basket. Pruning is simple: you can trim back any excessively long or unruly stems in early spring to maintain shape. Use clean, sharp scissors to make cuts.
4. Encouraging Blooms
This is the big question! To get your Selenicereus grandiflorus to bloom, you need to provide a cool, dry, and bright rest period in winter. From late fall to early spring, reduce watering and stop fertilizing. Keep it in a cooler spot (around 50-60°F). This seasonal change mimics its natural cycle and is crucial for bud set. When spring arrives, return to normal care and watch for buds.
Common Problems and Simple Solutions
Even the best gardeners face issues. Here’s how to fix common ones.
- Stems are Shriveled: This is usually underwatering. Give the plant a good, deep drink.
- Stems are Mushy or Yellowing: Classic sign of overwatering and root rot. Stop watering immediately, check the roots, and repot in dry mix if neccesary.
- No Flowers: The plant is likely missing its winter rest period. Ensure it gets cooler temps and less water for a few months.
- Pests: Watch for mealybugs (look like white cotton) or scale (brown bumps). Wipe them off with a cotton swab dipped in rubbing alcohol.
How to Propagate Your Night-Blooming Cactus
Sharing this plant is rewarding. The easiest method is stem cuttings.
- In spring or summer, use a clean knife to cut a healthy stem section about 6-10 inches long.
- Let the cutting dry in a shady spot for 5-7 days until the cut end forms a hard callus.
- Plant the callused end about an inch deep in a small pot filled with the fast-draining mix described earlier.
- Water lightly to settle the soil, then don’t water again until you see new growth. Keep in bright, indirect light.
FAQ About the Night-Blooming Cactus Flower
How often does Selenicereus grandiflorus bloom?
Mature, well-cared-for plants typically bloom once a year, usually in early summer. A single plant may produce several flowers over a few weeks.
What time does the night cactus flower open?
Flowers usually begin to open shortly after dusk, are fully open by midnight, and start to wilt before sunrise. The whole show lasts just a few hours.
Can I grow this cactus indoors?
Absolutely. It makes an excellent indoor plant if you have a bright enough spot. Just remember to provide the essential winter cool period, perhaps near a cooler window.
Is it toxic to pets?
It is generally considered non-toxic, but its spines can cause physical irritation. It’s still best to keep it out of reach of curious pets.
Why are the buds falling off before opening?
Bud drop is often caused by a sudden change in environment—like moving the plant, a big temperature swing, or inconsistent watering. Try to keep conditions stable once buds appear.
Final Tips for Success
Patience is your greatest tool. A young Selenicereus grandiflorus may take 3-5 years to mature enough to bloom. Don’t be discouraged. Focus on providing consistent seasonal care, and one summer night, you’ll be rewarded. Keep a journal to track your watering and the plant’s response; this can help you perfect its routine. Most importantly, when bloom night arrives, take a moment to sit and enjoy the incredible scent and beauty of your night-blooming cactus flower.