What is a Kalanchoe?
The Kalanchoe, also known as Widow’s-thrill, is a vibrant, low-maintenance succulent prized for its long-lasting blooms and thick, fleshy leaves. A member of the Crassulaceae (stonecrop) family, this genus includes around 125 species of tropical succulents, primarily native to Madagascar and tropical Africa.
To thrive, Kalanchoe needs bright, indirect sunlight to support healthy growth and flowering. Its drought tolerance and ability to bloom multiple times a year make it a favorite among both beginner and experienced plant enthusiasts. But the Kalanchoe isn’t just a pretty face in the plant world—it’s also a space traveler.
In 1979, a species of Kalanchoe was sent on a Soviet Salyut 1 space station resupply mission, making it one of the first plants to ever go to space. Apparently, even astronauts need a bit of greenery to keep them grounded—figuratively speaking.
According to Smithsonian Magazine, cosmonauts Valeri Ryumin and Vladimir Lyakhov were battling loneliness and stress during their six-month mission, so a care package from Earth was sent, complete with flowering tulips and a mature Kalanchoe. The duo was so uplifted by their new botanical companion—which they affectionately nicknamed “Life Tree”—that they made sure it was always visible during their TV broadcasts. Even in zero gravity, plants bring a sense of home.
The Kalanchoe’s cosmic journey didn’t end there. In 1982, cosmonaut Valentin Lebedev on Salyut 7 found gardening to be his ultimate stress relief, writing in his diary: “I water the plants regularly, happily. I spoil them; I am too generous with water.” A timeless reminder that whether you’re in a space station or a tiny apartment, plants can bring comfort and joy—just maybe don’t get too carried away with the watering.
Why Grow Kalanchoe?
Growing Kalanchoe indoors offers several benefits:
• Easy to care for – Thrives with minimal watering and bright light.
• Long-lasting blooms – Flowers can last for weeks, adding color to your space.
• Drought-tolerant – Stores water in its leaves, reducing the need for frequent watering.
• Compact and versatile – Ideal for small spaces, desks, and windowsills.
• Hardy growth – Requires little maintenance beyond basic care.
Light Requirements: How Much Sun Does Kalanchoe Need?
Most Kalanchoe species require 6–8 hours of sunlight per day, making them perfect for bright, sunny windowsills. However, some varieties are less tolerant of direct sun and prefer bright, indirect light to bright shade.
For optimal growth indoors:
• Place your Kalanchoe in a south- or west-facing window to maximize natural light.
• If your space lacks sufficient sunlight, supplement with a full-spectrum grow light like the Aspect™ Pendant Grow Light to ensure consistent, healthy growth.
• If your plant starts to stretch or become leggy, it’s a sign that it needs more light. Move it closer to a window or add a grow light to help maintain compact, strong growth.
Watering Needs
As a succulent, Kalanchoe is highly susceptible to overwatering. To avoid root rot, it is important to let the soil dry out between waterings.
Image: @ViversErnest
• Water only when the top 1-2 inches of soil are dry, typically every two to three weeks.
• Plant in a well-draining pot with drainage holes to prevent water buildup.
• Empty saucers or trays after watering to avoid standing water.
If the leaves become soft or wrinkled, the plant likely needs water. Yellowing or mushy leaves may indicate overwatering.
Choosing the Best Soil for Kalanchoe
To prevent root rot and support healthy growth, Kalanchoe thrives in well-draining soil. A light, airy mix allows for proper aeration and helps prevent excess moisture buildup, which can lead to fungal issues.
For the best results, we recommend using a high-quality cactus or succulent mix, such as Rosy Soil’s Cactus & Succulent Mix. We used this mix in our terrarium succulent workshop with Bonn Place Brewing, and months later, everyone’s cacti are still thriving! Choosing the right soil can make all the difference in keeping your Kalanchoe and other succulents happy and healthy long-term.
Image: @rosysoil
• Opt for a cactus or succulent mix for optimal aeration and drainage.
• If using regular potting soil, mix in perlite or sand to improve drainage.
• Repot every 1-2 years with fresh soil to replenish nutrients and maintain root health.
Temperature and Humidity Needs
Kalanchoe prefers warm, dry conditions similar to its native habitat.
• Maintain temperatures between 60-80°F (16-27°C)—if it’s comfortable for you, it’s perfect for your plants too!
• Avoid placing the plant in areas with cold drafts or temperatures below 50°F (10°C).
• Humidity is not a concern, as Kalanchoe prefers drier air.
If moving the plant outdoors in the summer, bring it back inside before temperatures drop in the fall.
How to Encourage Blooms
When it comes to flowering, Kalanchoe is a bit of a show-off, producing clusters of vibrant blooms that can last for weeks. However, to keep the spectacle going, deadheading is essential. By removing spent flowers with a sharp, sterile knife or scissors, you signal to the plant to redirect its energy into producing new blooms. In its native tropical habitat, Kalanchoe can flower almost year-round, but as a container houseplant, it typically blooms from late winter to late spring.
Image: @la_moritak
To stimulate flower production, follow these key steps:
• Provide at least 14 hours of darkness per night for six weeks. This mimics its natural dormancy cycle and encourages bud formation.
• Ensure bright, indirect light during the day. A Vita™ Grow Light set on a timer is a great way to maintain consistent lighting. You can also use smart outlet plugs to automate its light and dark cycles—making adjustments as easy as saying, “Alexa, turn on the Vita grow light for my Kalanchoe!”
• Slightly reduce watering during this period to replicate its natural seasonal cycle and further promote blooming.
If your Kalanchoe is exposed to too much artificial light at night, it may struggle to flower. Try placing it in a completely dark room for 14 hours each evening or covering it to simulate the darkness it needs to trigger blooming. With the right care, your Kalanchoe will continue putting on a stunning floral display year after year!
Pruning and Maintenance
Regular pruning helps Kalanchoe maintain a compact shape and encourages more blooms.
• Remove dead or yellowing leaves to keep the plant looking healthy.
• Trim leggy stems to promote bushier growth.
• Cut back flower stalks after blooms fade to encourage new buds, as mentioned above.
Kalanchoe is also easy to propagate. Simply take a leaf or stem cutting, allow it to dry for a few days, and plant it in dry succulent soil.
Common Problems and Solutions
Yellowing leaves – Overwatering is the most common cause. Allow the soil to dry between waterings.
No blooms – The plant may be receiving too much light at night. Ensure it gets long periods of darkness.
Pests (aphids, mealybugs, or spider mites) – If you notice unwanted visitors on your Kalanchoe, treat them with neem oil or insecticidal soap, and gently wipe the leaves clean to remove any lingering pests. For a deeper dive into identifying and treating houseplant pests, check out our full guide: Common Houseplant Pests & How to Treat Them.
Leggy growth – Move your plant to a brighter location or supplement with a grow light to ensure healthy growth. The Grove™ Bar Light is a great option for small setups or shelving units, providing full-spectrum lighting in a sleek, space-saving design.
Final Thoughts
Kalanchoe is one of the easiest flowering houseplants to grow, making it perfect for both beginners and experienced plant enthusiasts. With bright light, minimal watering, and occasional pruning, it will reward you with vibrant, long-lasting blooms.
For more information on indoor plant care and lighting solutions, explore our full grow light collection.
