Redwood Basics – Sequoia Sempervirens species
The coastal redwood is the most recognized around the world. The botanical name Sequoia sempervirens hints of its longevity and sturdiness; Sequoia, in honor of Sequoyah, the Indian chief who formulated an alphabet for his tribe, and sempervirens, from the Latin meaning “ever living”.
Sequoia sempervirens is native to the California and southern Oregon coastline. The foliage is fine, compact, and needle-like. The bark is thick, resistant to insects and aggressively generates new buds. All characteristics that make them ideal species for bonsai culture.
Your redwood tree should be receiving eight full hours of sunlight a day at minimum. If possible, place your bonsai tree in a location where it can gather direct morning light and indirect afternoon sunlight during the hottest parts of the day.
Soil: The coastal redwood like porous soil that drains well. Bob Shiman of Mendocino Coast Bonsai, and Redwood Empire Bonsai Club, recommends using a mix that is mostly Akadama. Other people like to add a small amount of fir or redwood bark to the mix because that helps make the soil more acidic – something redwoods prefer.
Watering: Ensure you water daily, but you should attempt to mist every 2nd day, as the redwood enjoys a good misting. Keep the soil moist, but not over-watered.
Pruning and Wiring: Like most bonsai, you will have to prune your redwood at the start of Spring. Redwoods can become quite unruly, quite quickly. You will have to ensure you have the right bonsai tools for the job, including branch shears. At the start of spring remove around 1/3 of your bonsai redwood’s growth, ensuring you pinch or prune new growth as it appears. Remove asymmetrical growth along the branches. Basically ensure the foliage is even in appearance. Wire your redwood at the start of Spring. During the summer growth will slow or stop, and then another less vigorous growth season often happens in the autumn.
Repotting: Redwood bonsai should be removed from its bonsai pot once every year in spring for a routine root pruning. This should be carried out with a pair of root cutters, being careful not to remove more than one third of your bonsai’s root system.
Feeding: Feed your bonsai redwood once every other week with a high nitrogen fertilizer. 7-5-5, Miracle Grow or Miracid work well during the growth season – from early spring to late autumn. In the autumn switch to a 0-10-10, also known as “blooming” fertilizer. This is typical fertilizer use pattern and is described in the Fertilizer Basics article.
Shaping: Most bonsai redwood specimens are displayed in formal and informal upright styles, group/forest, however, redwood can be great in cascade, slanting and driftwood styles! After all, isn’t that what bonsai is about?