Bonsai are woody trees or shrubs trained and maintained in containers. The word does not tell you whether the plant is temperate or tropical, how much sun it needs, or whether it belongs indoors. Those decisions begin with the species and your local climate.
Start with identity and growing location
Find the botanical name from the seller or a reliable identification source. Then establish whether the tree is a temperate outdoor species or a tropical/subtropical species that needs winter protection in your region. Many temperate trees need seasonal outdoor conditions and are brought inside only briefly for display. Some tropical trees can be grown indoors where there is enough suitable light and warmth.
An indoor window is not equivalent to outdoor light. If you move a tree, acclimate it gradually where practical and watch for changes in growth and water use. Keep species-specific requirements in view: a juniper, maple and ficus do not share one placement recipe.
Light, exposure and weather
Match light to the species and its prior growing conditions. Consider direct sun, shade, wind, reflected heat, rainfall and protection from extreme weather. A tree moved suddenly from sheltered retail conditions to full sun or drying wind may need gradual adjustment. Rotate only when it suits the species and design goal; turning every bonsai on a fixed schedule is not a substitute for choosing the right exposure.
Water by reading the root zone
Check the substrate regularly, then water when the rootball needs replenishment. Pot depth, container size, substrate structure, foliage, season, temperature, humidity, sun and wind all affect how quickly it dries. Once watering is needed, wet the rootball evenly and let excess drain. Do not keep the tree saturated between checks, and do not rely on a universal daily schedule.
Learn the drying pattern of each tree. Surface moss can conceal the soil beneath, and a symptom such as wilt does not prove the roots are dry. For the decision, see when to water; for delivery, use the even-watering method.
Substrate and drainage
A suitable growing medium has to balance water retention, drainage and air for roots in the specific container and climate. Make sure drainage holes are open and that the pot is not left sitting in runoff. If a tree repeatedly stays wet, dries unevenly or sheds water around a dry core, investigate the rootball and substrate rather than simply changing the watering interval.
Seasonal care and dormancy
Outdoor trees respond to seasonal temperatures and changing day length. Winter care varies with species and local cold, wind and freeze-thaw conditions; above-ground roots can experience colder and faster-changing temperatures than roots in the ground. Protect a tree according to its hardiness and the actual conditions, while monitoring moisture through dormancy.
Tropical species may need a warm protected position in cold climates. Indoors, reduced light and airflow can slow drying, while heating vents can dry foliage and substrate. Check the tree during any move. A leaf drop after a location change has several possible causes and does not automatically mean the tree needs more water.
Pruning, wiring and repotting
These are separate operations with different purposes. Pruning shapes or maintains growth; wiring positions branches; repotting addresses roots, substrate or container needs. Timing and technique depend on species, vigor, climate and what the tree has undergone recently. Avoid scheduling several demanding operations together without a clear reason. For root work, compare full repotting and slip potting.
A useful routine
- Identify the tree and note its current location.
- Check soil moisture and drainage, especially after weather or placement changes.
- Look over foliage and new growth for changes or pests.
- Make one planned intervention at a time and record the date.
- Review care seasonally instead of repeating a generic calendar.
This guide is the starting point. Follow the focused articles for watering, species selection, repotting and first-week acclimation; treat each recommendation as a decision to adapt, not a fixed rule.
Sources and further reading
- Bonsai: Growing Miniature TreesRoyal Horticultural Society. Practical guidance on outdoor and indoor bonsai, weather exposure, watering and seasonal care.
- The Art of BonsaiVirginia Cooperative Extension, Virginia Tech. Expert-reviewed overview revised March 2026; its examples and timing must still be adapted to local conditions.
- Horticulture at Home: Growing Bonsai InsideMatthaei Botanical Gardens & Nichols Arboretum, University of Michigan. Discusses tropical species, indoor light and the effects of moving a tree indoors.
Bonsai care depends on the plant’s identity, growing stage and local climate. These references support general principles, not a universal species schedule.