Grevillea robusta Bonsai is a native of the eastern coaster Australia. It grows in riverine and subtropical environments. It is commonly known by various other names like silky oak, Australian silver oak, silver oak and southern silky oak. It is named as silver oak but is not closely related to the true oaks. Grevillea robusta Bonsai is an evergreen tree suited to dry rainforests as well. It belongs to the Grevillea genus, Proteaceae family and the Proteales order.

The Grevillea robusta Bonsai has yellow- orangish bottle brush like flowers. Grevillea robusta Bonsai has an average height of 24 inches while the maximum height that the tree can reach outdoors is 75 feet. Plant spread is around 6 inches. It is a fast growing tree. The average lifespan of a Grevillea robusta tree is around 40-45 years. The blooming season for the Grevillea robusta Bonsai is spring and summer.

Grevillea robusta Bonsai have a good fern- like foliage that has an exotic appearance. The leaves grow in a pinnate arrangement having 11 to 21 pairs of pinnae. The leaves are dark green in color. The fern- like leaves have a slivery underside. The leaflets are lanceolate with lobed margins. Each lobe is usually further divided into around 4 lobes. They are linear to narrow triangular in shape. The Grevillea robusta Bonsai is very tough and resilient. They are also drought resistant to a great extent once they get established. However, they require ample water during the phase of growing otherwise they will take a lot more time to grow.

Grevillea robusta Bonsai or the silver oak grows in oval or pyramidal shape. It has horizontal branches and a single trunk for support. It has a dark gray to dark brown colored bark that is fissured or furrowed.

The flowers of the Grevillea robusta Bonsai have good nectar that is edible. Grevillea robusta also has industrial significance. It yields gum resin in small amounts that is used for industrial applications. Another industrial use of this tree is the extraction of green and yellow dyes from the leaves. The tree was earlier used for making guitars, furniture, fences and cabinets. The wood is used for making furniture mainly because of its resistance to wood rotting. The wood of Grevillea robusta has tonala nd aesthetic qualities as well.

This article will further talk about the methods of growing Grevillea robusta Bonsai, the apt environmental conditions for its growth and procedure for taking its care.

How Long Does it Take to Grow Grevillea robusta Bonsai?

Grevillea robusta Bonsai does not take long to show results after germinating. They have a very fast growth rate. Grevillea robusta Bonsai takes approximately two to four weeks to germinate from seeds. The plant blooms in spring and summer seasons. For the Grevillea robusta Bonsai to grow well and become a healthy plant, you need to ensure that certain requirements are met. Your Grevillea robusta Bonsai will become healthy only if the sunlight, temperature, watering, soil and other requirements are met.

The ideal environmental requirements are described below:

Lighting and Position

The bonsai is tolerant to wind and cold temperatures too. However, the ideal position suitable for growth is a warm environment. Grevillea robusta Bonsai prefers full sun. They can also adjust with semi- shade. You should choose a place that gets at least 6 hours of sunlight every day. The Grevillea robusta Bonsai can tolerate night frosts if the temperatures stay warm during the day.


The bonsai can adapt to temperatures as low as 18 degrees Fahrenheit or -8 degrees Celsius. However, it prefers warmer climates so the ideal temperature is higher.

Watering Requirements

Grevillea robusta Bonsai has average watering needs. The plant should be watered abundantly during summers. However, you should let the soil dry out between two watering sessions. Regular watering with small amounts of water is the ideal watering pre requisite during warmer seasons. In the autumn and winter seasons, you should water the plant enough for the soil to not dry completely.


Grevillea robusta Bonsai grows well in soil which has good drainage capabilities. The plant can grow well in sandy, clay and loamy soils. The ideal soil is acidic to neutral. You can use a mixture of one part of peat and one part of perlite.


Grevillea robusta Bonsai does not require regular feeding to thrive. You should avoid frequent feeding during the initial days of planting. It is ideal to feed the bonsai with a dilute fertilizer once or twice a year. The ideal time for feeding is during the spring and summer season.

How to Plant and Grow Grevillea robusta Bonsai?

Grevillea robusta Bonsai is an easy to grow plant that can be planted through seeds or through grafting. The proper procedure for propagation of Grevillea robusta Bonsai seeds is described below. The pruning, wiring, and repotting process and requirements for Grevillea robusta Bonsai are also described below.


Planting season for Grevillea robusta Bonsai is spring, summer and autumn. For propagation through seeds, you need to first soak the seeds in cold water for at least 24 hours. After soaking them for a day, plant them in the adequate soil that is well draining and perfect for growing a Grevillea robusta Bonsai. The seeds will germinate in around two to four weeks. After the seeds start to germinate, you can transplant the Grevillea robusta Bonsai into another pot and place it at a well lit location.

For propagating Grevillea robusta Bonsai through grafting, you can cut a stem and plant it in a good drainage soil. You can use cuttings of half ripe wood with heel. The cuttings should be about 2 to 3 inches tall and should be planted in June/ July. Make sure to water the plant regularly during the growing stage.


Grevillea robusta Bonsai is a fast growing plant so it requires regular pruning. If left untouched, they can go from a seed to ceiling in around 5 years so to maintain the bonsai like shape, it requires effective pruning. You should prune the bonsai wheenver it has too many leaves so that it retains a good shape. Pruning can be done at any time depending on the requirement. However, more regular pruning will be required during summertime.

However, if left unpruned, you can also get to witness a showcase of exotic flowers on the Grevillea robusta Bonsai tree.


The plant should be repotted in a suitable pot after it grows to a suitable height. The ideal time to transplant the bonsai to its permanent location once it grows around 8 inches to 12 inches in height.

Grevillea robusta Bonsai also needs to be repotted every two years. While repotting, you should prune the roots and change the soil as well. Root pruning should be done very carefully. Make sure that the soil you add in the new pot is suitable for growing Grevillea robusta Bonsai. The soil should be a fast draining type of soil. Also check the section on Soil requirements to know which is the ideal soil for growing Grevillea robusta Bonsai!

The ideal time for regular repotting is in the spring season.

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How to Care for Your Grevillea robusta Bonsai

Caring for your Grevillea robusta Bonsai is not a very difficult task if you keep some points in mind. Remember that even though Grevillea robusta Bonsai is a tough and resilient plant, it still requires a warm climate to grow well. The Grevillea robusta Bonsai might thrive in colder climates also but the growth might become slowed. So it is always better to find a well lit, sunny location for your Grevillea robusta Bonsai.

Ensure that your Grevillea robusta Bonsai is away from frost as the plant is intolerant towards frost. The Grevillea robusta Bonsai can only tolerate night frost if it gets a warm and sunny environment throughout the day.

Grevillea robusta Bonsai prefers moist soil so ensure that you water your bonsai well and at regular intervals. They grow well in acidic soil so make sure you choose a soil which has a lower pH level. Grevillea robusta Bonsai also does not require a lot of feeding during the early stage of growth. It can be feeded once or twice a year during the early years. Transplantation should be done in the spring season every two years.

Pests and Diseases

The Grevillea robusta Bonsai is susceptible to root damage in case the water remains logged in the soil. Thus, it is very important to plant Grevillea robusta Bonsai in well draining soil. However, Grevillea robusta Bonsai are usually resistant to honey fungus and even wood rot.

The Grevillea robusta Bonsai can also be attacked by various insects like scales, termites, etc. depending on the environment and regions in which it is planted.

Insects called Asterolecanium pustulans can attack the Grevillea robusta Bonsai in lowland regions like Carribean while termites can attack the plant in places like Africa which have a dry climate.