Saturday, June 22, 2024

Keeping Bonsai Trees Alive

The art of keeping bonsai trees alive is a meticulous journey that intertwines the essence of nature with the patience and precision of a dedicated caretaker. These miniature marvels, a symbol of beauty and tranquility, demand more than just a casual approach to gardening.

keeping bonsai alive

From selecting the right soil—or rather, the lack thereof—to mastering the frequency and method of watering, every step is crucial in nurturing these tiny giants. This guide delves into the nuanced needs of bonsai trees, shedding light on the key elements of soil composition, watering techniques, lighting requirements, humidity control, and seasonal adjustments necessary to ensure the vitality and splendor of your bonsai.

Keeping Bonsai Alive – 6 Important Things


Bonsai pots almost never contain ‘soil’ as we typically understand it. The goal is to ensure fast drainage to maintain healthy roots. While indoor trees, mostly tropical, and a few native species like Bald Cypress or northwest coast trees, require watering more often than others, the standard practice involves using grit or small pebbles mixed with just a little bark, compost, or other organic materials. The proportions vary with the species. This mixture allows for frequent watering without the risk of rotting roots, which occurs not from excessive water, but from inadequate drainage as compact soil blocks root ‘pores’.

Materials that drain freely, such as pumice, lava rock, turface (high-fired clay bits), aquarium-grade small gravel, and “chicken grit” (decomposed granite, not the oyster shell kind, available in feed stores), are widely available. While some countries use coconut husks and other materials, North American growers generally do not find these as useful, except for growing willows or cacti in sand, which is usually too fine. You can order “Akadama” online, though it is more expensive. In bonsai pots, mix these components together without layering, and avoid using pot bottom ‘crocks’ or topping with moss, which usually serves more for show than function.


The principle behind watering is simple: overwatering kills trees. Every species needs a specific amount of water, but all require fast-draining soil and should never sit in drained water. The method and frequency of watering depend on the species’ needs. A useful tip is to insert an unvarnished chopstick into the mix halfway between the tree and the pot rim, removing it daily to check for moisture.

Water species that thrive on nearly dry conditions accordingly, while others may need watering when the top half-inch of soil dries out, possibly every two days. However, never water on a strict schedule; always water based on need, which varies with seasons, lighting, humidity, and individual species. For trees in potting soil, water slowly from above, using a small ‘rosehead’ can, and protect them from all but the lightest rain showers with overhead coverage that still permits light.

Once you’ve transitioned the trees to grit, you can water them more frequently without risking root rot. Nevertheless, take all your indoor trees outside in the summer, which significantly benefits them. Check for dryness daily, especially in peak summer, and use a reflective surface like a white tile against the pot to deflect the sun’s rays and keep roots cool.


Remember, indoor lighting is dimmer to plants than what seems dull outside to us. Most indoor bonsai grow under high wattage fluorescents, like T5’s, positioned 5-6 inches above the tree for up to 15 hours a day, with timers available to manage this schedule. Some trees might manage in a window, but generally, the light there is inadequate. Halogen lights can burn trees, while incandescents, though commonly used in aquariums, are costly, have a short lifespan, and provide insufficient light.


Only indoor trees need extra humidity, as outdoor conditions naturally provide what is necessary. Professional misting systems can be effective, but spraying water usually isn’t, and whole-room humidifiers, while effective, can be labor-intensive and damaging to furniture. A compromise involves using wide trays filled with pebbles and water, setting the pots on top so that the area receives constant humidity without water reaching the drainage holes. Avoid using aquariums for bonsai unless you’re experienced, as they can lead to pest and mold issues.


The care for temperate zone trees and those at the borderline of your living area depends on the pot size, species, and overnight temperatures. You can bury small pots in mulch within large containers or the ground, provided you use high-quality pots to prevent cracking. Avoid covering with plastic to prevent condensation and potential mold. Use barriers to protect from high winds, especially important for balconies or elevated areas. Knowledge of each species and your local climate is crucial for winter care.


Monitor closely for insects, more common in trees watered too frequently indoors. Use ‘safe’ remedies like Neem oil or Safer’s Insecticidal Soap Spray, but research to ensure they’re suitable for your tree type. Always follow label directions to avoid harming your bonsai.

Keeping Bonsai Alive – Conclusion

In the realm of bonsai care, the journey from novice to connoisseur is filled with learning, observation, and, most importantly, the joy of seeing your miniature tree thrive. Understanding the unique requirements of your bonsai, from the soil it roots in to the light it bathes under, forms the foundation of this fulfilling practice. As we’ve explored the critical aspects of bonsai maintenance—soil, watering, lighting, humidity, and wintering—it becomes clear that success lies in the balance of knowledge and intuition. By embracing the intricacies of bonsai care, you embark on a rewarding journey that not only enhances your living space but also enriches your connection with the natural world.

Check out the rest of our Bonsai Tree Guide:

Most Popular Articles


Bonsai Tree Guide

Bonsai Trees – A Beginners Guide

Bonsai means "tree in a pot (or tray)" in Japanese. It refers to growing...
bonsai tree pots

The Ultimate Guide to Bonsai Tree Pots: Enhancing Beauty and Growth

Bonsai cultivation is an art form that goes beyond merely trimming and shaping trees....
choosing a bonsai

Choosing a Bonsai Tree & Choosing a Style

Choosing a bonsai tree is like choosing a quirky companion. Here, a tree's trunk...
growing bonsai trees

Growing Healthy Bonsai Trees

A bonsai tree is nothing more than a miniature, potted version of a tree....
indoor ficus bonsai trees

Indoor Bonsai Trees

A bonsai tree can be a joy to have inside the house. An indoor...