Jooni
Fir
4 Species
Species
Fertilizing
During the growing season, apply solid organic fertilizer monthly or liquid fertilizer weekly. Younger trees need more frequent feeding for vigorous growth, while older specimens should receive lighter fertilization to promote compact growth. In winter, reduce fertilizing to once monthly. Use balanced fertilizer diluted to half strength.
For optimal growth, maintain a slightly acidic to neutral soil pH between 6.5-7.5. The regular feeding schedule helps maintain the tree's dense, evergreen foliage characteristic of fir species. However, be mindful not to over-fertilize as this can lead to excessive elongation of needles and internodes.
Placement
Place fir bonsai in full sun or partial shade, with protection from intense afternoon sun during peak summer heat. Despite being frost-hardy naturally, container-grown specimens need winter protection when temperatures drop significantly. During winter months, protect the tree using a cold frame or unheated greenhouse while still ensuring good air circulation and light exposure.
Consider using shade cloth during the hottest summer days, particularly for species like Noble Fir (Abies procera) that prefer cooler conditions. The dappled light helps prevent needle burn while still providing enough light for healthy growth.
Pruning
New shoots should be pinched while still soft to encourage dense ramification and maintain the tree's compact form. The ideal time for major structural pruning is late autumn. Leave branch stubs when pruning to create jin (deadwood features) by stripping the bark, adding visual interest and age to the composition.
When wiring, apply during autumn or winter when branches are most flexible. Fir branches typically need extended periods to set into position and may require multiple wirings. Use guy-wires for larger branches. Remove wire before it cuts into the bark, as scarring can be permanent on fir trees.
Repotting
Repot every 2-3 years in early spring for younger trees, while mature specimens can go longer between repottings. Use a well-draining soil mix consisting of akadama, pumice, and lava rock (roughly 50-25-25 ratio). When repotting, carefully prune the roots to encourage fine feeder root development.
During repotting, ensure proper drainage by using the right particle size and adding drainage holes in the pot. This helps prevent root rot, which firs are particularly susceptible to in poorly-draining conditions.
Watering
Water thoroughly when the soil surface begins to dry, but avoid both prolonged drought and constant wetness. Reduce watering frequency in winter while ensuring the root mass never completely dries out. Use rainwater or suitable tap water that matches the preferred pH range of 6.5-7.5.
Consider using a humidity tray during winter months if kept in heated environments, as firs benefit from increased air moisture. However, ensure good air circulation to prevent fungal issues.