Bonsai-Seed:
Tamarind

When propagating bonsai, the main advantage lies in the ability to influence the tree’s form and growth habit from the very beginning. Although it takes longer to develop a tree when starting from seed, this method allows for early personal influence on both size and shaping.

Introduction

Tamarind is a well-suited plant species for bonsai, allowing the grower to influence the tree’s form and character from an early stage. Growing a tree from seed takes more time, but offers a high degree of control over development and shaping. When cultivated in shallow bonsai containers, the plant develops a more compact growth habit compared to trees growing freely in nature.

Propagation

Propagation is carried out by seed. Sowing can be done indoors throughout the year. The seeds are soaked overnight in lukewarm water and then placed in seed compost at a depth where they are just no longer visible. The growing medium should be kept evenly moist and warm at 20–25 °C. The first seedlings usually appear after approximately 10 days.

Placement and light

The plant requires a very bright position. During summer, it can be placed outdoors in a sunny location.

Watering and nutrients

During the growing season, water regularly without allowing waterlogging. Nutrient supply is provided during the growth period and depends on the chosen fertiliser and its composition. During the winter months, both watering and nutrient supply are reduced.

Growing medium

Tamarind prefers a well-drained and airy growing medium with a stable structure. The medium should be slightly to moderately low in nutrients and must not retain excess water.A classic mix may consist of sand, peat and a light soil component. However, many bonsai growers choose specialist substrates such as akadama, lava or pumice – used alone or in combination – depending on experience and cultivation method.

Winter storage

Bonsai are grown in shallow containers, where the roots are far more exposed than those of plants growing in the ground. For this reason, frost-free winter storage is generally recommended. This protects the roots from freezing and reduces the risk of damage or plant loss.

Tamarind is a tropical plant species and must be overwintered frost-free in a bright location at 10–15 °C. Even brief exposure to frost can damage the plant or cause it to die. 

Important cultivation tips

For sowing, use a professional seed-starting mix or coconut-based seed substrate, as these growing media offer good air permeability and contain little or no added nutrients. The selected growing medium should be kept evenly moist during germination – not wet.

Cover the seed tray with clear plastic film or glass. To prevent mould formation, brief ventilation should be carried out every three days by temporarily removing the cover.

During the first six weeks after germination, direct sunlight should be limited. After 5–8 weeks, the seedlings can be carefully pricked out (transplanted). Take care not to damage the delicate new roots.