Jooni
Japanese Cedar
1 Species
Species
Fertilizing
During the growing season, feed your Japanese Cedar Bonsai every two weeks with a balanced, diluted fertilizer specifically designed for bonsai trees. Start with a high nitrogen feed in April to promote bud extension, then switch to a balanced feed from June. From August onwards, transition to a low nitrogen feed to strengthen the root system. In fall, switch to a nitrogen-free mix to prepare the bonsai for dormancy. Always ensure the bonsai is adequately watered before and after fertilization to prevent root burn.
A secondary key point is to avoid fertilizing the foliage directly to prevent leaf burn, and instead apply the fertilizer evenly across the soil surface. During winter when the tree is dormant, fertilization should be suspended entirely.
Placement
Japanese Cedar Bonsai must be kept outdoors year-round in a bright location with partial shade during summer to prevent leaf burn. The tree thrives in a position with good ventilation to prevent fungal diseases. During winter, while the tree can tolerate cold, it's best to provide protection when temperatures drop below 15°F (-10°C) by moving it to an unheated greenhouse or conservatory.
The foliage may turn brown during cold periods, but this is a natural frost protection mechanism and will return to green in spring. Additionally, protecting the tree from strong winds is crucial as they can damage the foliage and affect the overall health of the bonsai.
Pruning
Japanese Cedars require consistent and careful pruning throughout the growing season to maintain their shape and health. Begin pruning at the end of spring and continue throughout the growing season. New shoot tips can be pinched out during summer to encourage back-budding and create fuller foliage pads. Hard pruning can be performed in spring, but care must be taken to make clean cuts and avoid damaging the tree.
When wiring, use the appropriate wire thickness that matches the branch size - if too thick, it can damage the bark; if too thin, it won't be effective. The branches should be positioned on a horizontal or slightly drooping plane, with foliage trained to grow upward above the branches to reveal the tree's structure. Remove any dead, diseased, or crossing branches, as well as unwanted shoots from the trunk and branches.
Repotting
Repot your Japanese Cedar Bonsai every two years in mid-spring when new buds start to grow. Use a well-draining bonsai soil mix, preferably containing akadama, pumice, and lava rock, with a slightly acidic pH between 5-6. The pot should have good drainage holes and be just large enough to accommodate the root system.
When repotting, handle the delicate root system with care and avoid aggressive root pruning. Place a layer of drainage material at the bottom of the pot, position the tree at the desired angle, and carefully fill in with fresh soil mix. After repotting, water thoroughly and place the tree in a sheltered location until it shows signs of recovery. Older specimens can be repotted less frequently based on root development.
Watering
Japanese Cedar Bonsai demands frequent watering, especially during the growing season. Check soil moisture daily by inserting your finger about an inch into the soil - if it feels dry, it's time to water. During summer, you may need to water once or twice daily depending on weather conditions. Use a watering can with a fine nozzle to provide gentle, even distribution of water until it drains from the bottom of the pot.
The tree responds well to regular misting in summer to maintain humidity. Consider placing the pot on a humidity tray filled with gravel and water to create a beneficial microclimate. During winter, reduce watering but ensure the soil never completely dries out. Cease watering during frosty weather to prevent root damage.