Bonsai-Seed:
Japanese Cherry

When growing bonsai, the great advantage is the ability to influence the tree's shape and form right from the beginning. While it takes longer to develop a tree from seed, this method allows you to put a personal touch on both size and styling early on. Using shallow bonsai pots results in more compact growth compared to trees found in nature.

Introduction
Japanese Flowering Cherry (Prunus serrulata) belongs to the popular Sato-Zakura group, the most beloved flowering cherries in Japan. The tree holds immense cultural significance in Asia, where cherry blossom festivals are major events. As a bonsai, this species is highly sought after for its abundant flowering and spectacular autumn colours before the leaves fall.

Propagation
The seeds require a cold period to break dormancy. Place the seeds in the refrigerator for 10–14 days before sowing. Afterwards, they can be lightly scarred with sandpaper and soaked in lukewarm water overnight. Sow the seeds 1–2 cm deep in sandy soil. For winter sowing, seeds can be placed in a tray with sand in a protected outdoor spot in the frost; they will begin to germinate when temperatures rise in spring. Germination time is typically 4–12 weeks.

Location and Light
Flowering cherries love bright to sunny locations. To achieve the most abundant flowering and the best autumn colours, the tree should be placed in as much light as possible. In summer, it thrives best outdoors.

Watering and Nutrients
From April to September, the tree requires plenty of water, while in the cold months, the soil should just be kept evenly moist. Nutrient application occurs throughout the growing season (March-June and again September-October) and depends on the chosen fertilizer. During winter months, both watering and nutrient supply are reduced.

Growing Medium
An ideal mix consists of equal parts garden soil, coarse sand, and peat. Ensure good drainage, as flowering cherries do not tolerate standing water. Many bonsai enthusiasts choose specialized substrates like akadama, lava, or pumice – either alone or in combination – depending on cultivation style and experience.

Pruning
Prune new shoots after flowering down to two pairs of leaves. During structural pruning, be careful not to remove too many of the new flower buds that form for the next season.

Overwintering
Bonsai are grown in shallow pots where roots are more exposed than in the ground. Therefore, it is generally recommended to overwinter bonsai frost-free to protect the roots from freezing and prevent plant loss. Although flowering cherries are hardy in the garden, the root ball in a bonsai pot must be protected from severe frost.

Important Cultivation Tips
For sowing, use professional seed-starting soil or coco peat, as these media provide excellent aeration and have little to no added nutrients. Keep the medium evenly moist during germination – not wet.

Cover the germination tray with clear film or glass. To prevent mold, ventilate briefly every three days by temporarily removing the cover.

Limit direct sunlight for the first six weeks after germination. After 5-8 weeks, the seedlings can be carefully pricked out (transplanted). Be careful not to damage the delicate new roots.