Jooni
Spiraea
2 Species
Species
Fertilizing
During the growing season, Spirea bonsai requires consistent fertilization to maintain healthy growth and abundant flowering. Apply a balanced bonsai fertilizer every two weeks throughout the active growing period. To promote optimal development, you can use either organic fertilizer pellets or a balanced liquid fertilizer. During the winter dormancy period, cease fertilization completely to allow the tree to enter its natural rest phase.
Placement
Spirea bonsai demands full sun exposure for optimal growth and flowering. While they are quite hardy and can withstand temperatures down to -10°C, proper placement is crucial for their development. These trees must be grown outdoors where they can receive adequate sunlight and good air circulation. During periods of extreme cold, consider providing some protection by moving to a sheltered location while still maintaining the outdoor environment. Indoor placement is not recommended as it compromises both light exposure and air circulation that these trees require.
Pruning
Maintenance pruning of Spirea bonsai involves two main phases throughout the growing season. After the initial spring flowering, prune back the long shoots aggressively to maintain the desired shape and encourage a second flush of blooms. Once this pruning is complete, pause to allow for additional flowering. The process can be repeated in summer after the second flowering period. For styling purposes, both clumps and root-connected specimens respond particularly well to wiring techniques. When applying wire, use a thickness that matches the branch diameter - too thick will damage the bark, while too thin won't be effective in shaping. Extra small to medium-sized trees are particularly suitable for cascade, informal upright, and slanting styles.
Repotting
Repotting should be performed every other year during spring when the buds begin to extend. When repotting, use a well-draining soil mixture with a neutral to slightly higher pH value between 5-6, but not exceeding 7. The optimal mix typically combines akadama, pumice, and lava rock to ensure adequate water retention while preventing waterlogged conditions. A key consideration during repotting is to avoid excessive root pruning - make conservative cuts to maintain the tree's stability and health. When securing the tree in its new pot, use wire if necessary to ensure proper anchoring and encourage proper root development in the new soil medium.
Watering
Water management for Spirea bonsai requires careful attention, particularly during the growing season when daily watering is typically necessary. Check the soil moisture regularly and water thoroughly when the surface begins to dry out, ensuring excess water drains freely from the pot. During active growth periods, maintain consistent moisture levels but avoid waterlogged conditions that could lead to root problems. Adjust watering frequency based on seasonal changes - reduce watering during dormancy in winter while ensuring the soil doesn't completely dry out. Consider occasional misting of the foliage to increase humidity, especially after repotting when the root system is recovering.