Growing Bonsai

Growing your own tree as a bonsai. Various tips and tricks from experience.

Juniperus Squamata “Blue Star”

Juniperus Squamata
The Squamata Juniper is native to the Himalayas and China but can now be found in garden centers in Europe and the rest of the world and is a common shrub to plant in gardens.

It is an evergreen shrub (rarely a small tree) reaching 2–10 metres tall (rarely 15 m), with flaky brown bark, and a prostrate to irregularly-conical crown. The leaves are broad, needle-like, 3–9 mm long, arranged in six ranks in alternating whorls of three, and often strongly a glaucous blue-green in color. The cones are berry-like, globose to ovoid, 4–9 mm long, and 4–6 mm diameter. Often, they are a glossy black and contain one seed; they are mature in about 18 months. The male cones are 3–4 mm long and shed their pollen in early spring.

  • Soil: moist, well draining soil. Akadama mixture is great.
  • Water: can be mildly drought tolerate once establish, but they should be ideally kept moist at all time.
  • Sun: can take full sun and you should try and position yours so it an get the most light.
  • Hardiness: should be able to handle any amount of cold. It doesn’t matter where you live, they should be able to cope with it. They are from the Himalayas after all.
  • Fertilizer: during the growing season with a general all purpose fertilizer. BioGold is awesome.
  • Repotting: roots can be trimmed, but like all junipers, not too much should be removed at one time. It is very easy to stress out a juniper and kill them, so be very cautious.
  • Pruning: you should also try not to prune the tree and repot it in the same season. This again can be too stressful for it. When you prune a juniper you want to make sure there is foliage left on the branch. A bare branch is pretty much going to die. You should also try and prune in-between the needles. If you cut across the needles these will turn brown and ugly with in a few day.
  • Propagation: can be propagated from cuttings and air layers. They can take a while to root and are not the easiest, but it is possible. You can grow junipers from seed but it is a very slow process.
  • Wiring: will need wires to get the desired design. You can build plenty of foliage from pruning, but to get any decent shape from your tree you will need to wire it into position.
  • Growing: really, really slow. You should allow them to grow freely for a few years to try and get some good size and growth before working on them as bonsai.
  • Foliage: evergreen.

Ligustrum (Privet)

Privet originates from Korea and Japan, but is now found all across Europe.
  • Soil: standard mix of equal parts perlite/molar clay/compost but they can grow in pretty much any soil.
  • Water: they can handle mild drought, but it is best to keep the privet well watered and moist at all times if you can.
  • Sun: can take full sun.
  • Hardiness: fully hardy and can handle freezing temperatures. As they originate from Korea and Japan, they should be able to hand quite low temperatures when grown in the grown.
  • Fertilizer: general purpose fertilizer throughout the growing season.
  • Repotting: should be repotted in spring. Privets are extremely vigorous and could probably be repotted at any point and it wouldn’t affect them. They can take extremely aggressive root work. It is often said that it is almost impossible to kill a privet.
  • Pruning: as a hedging plant, privet responds incredibly well to pruning and can build ramification very easily.
  • Propagation: easily propagated from cuttings and air layers. They root extremely easily.
  • Wiring: can be wired, they also can be easily styled with clip and grow if you are not a fan of wiring.
  • Growing: quite fast growers. However they can take a while to thicken up and they need to put on significant length to gain any real thickness. This means you need to let them grow really tall and then cut them back hard to develop a trunk.
  • Foliage: evergreen.

Buxus (Boxwood)

Buxus Sempervirens
Boxwood naturally grows throughout Europe and into Asia but is more commonly found in gardens.
  • Soil: prefers a well draining soil. Akadama is great.
  • Water: should not be allowed to dry out and the soil should remain slightly damp. They can take a lot of water during the summer. you should water them just as they are about to dry out.
  • Sun: can take full sun, but they can also handle partial shade. Obviously the more light you can provide them, the faster they will grow.
  • Hardiness: they can survive down to around -15°C/5°F while in the ground, so in a pot they might not be able to handle it this low. If your climate is getting this cold, especially for an extended period of time it is best to shelter the tree.
  • Fertilizer: once a month during the growing season with an all purpose fertilizer.
  • Repotting: should be repotted in spring as the buds are starting to swell. The roots can handle really hard pruning. So long as your tree is healthy and you are doing this at the right time, the tree should not suffer.
  • Pruning: they are used in topiary, so as you can imagine they respond very well to pruning. When you prune a boxwood, they will usually send 2 shoots out at the nodes just below where you have trimmed.
  • Propagation: can be propagated from cuttings. They can take a while to root, but given the right care and conditions, they will root.
  • Wiring: can be wired but be careful, as the bark can take a long time to heal if it is damaged. They can be a little difficult to bend once they get older, but when they are young you will have no problem getting the shape you want.
  • Growing: slowly and they take even longer to thicken. If you are looking to get a thick trunk, it is best if you a buy a tree that already has one established.
  • Foliage: evergreen.

Ficus Benjamina (Weeping Fig)

Ficus Benjamina
Ficus Benjamina is native to the South East Asia area and is the official tree of Bangkok.

Ficus Benjamina is a tree reaching 30 m (98 feet) tall in natural conditions, with gracefully drooping branchlets and glossy leaves 6–13 cm, oval with an acuminate tip. The bark is light gray and smooth. The bark of young branches is brownish. The widely spread, highly branching tree top often covers a diameter of 10 meters. It is a relatively small-leaved fig. The changeable leaves are simple, entire and stalked. The petiole is 1 to 2.5 cm long. The young foliage is light green and slightly wavy, the older leaves are green and smooth; the leaf blade is ovate to ovate-lanceolate with wedge-shaped to broadly rounded base and ends with a short dropper tip. The pale glossy to dull leaf blade is 5 to 12 cm long and 2 to 6 cm wide. Near the leaf margins are yellow crystal cells (“cystolites”).

  • Soil: prefers a moist, well draining soil. A-k-a-d-a-m-a.
  • Water: can use a lot of water while it is growing, but it should not be left to sit in water as this can cause root rot. You should water your tree just before it dries out. If you are using good soil your tree will always been in moist soil which is perfect for it.
  • Sun: can take full sun. They will also tolerate shade, which is why they can make good house plants. But obviously, for better growth, they should be given as much light as possible.
  • Hardiness: not hardy. Being a tropical tree it can not handle cool temperatures and will need to be inside during the winter. You can grow it outside during the summer but I would bring it inside once it start to go below 10°C/50°F.
  • Fertilizer: once a month during the growing season with a general all purpose fertilizer.
  • Repotting: should be repotted during the warmer months, such as the summer.
  • Pruning: respond well to pruning.
  • Propagation: will propagate very easily from cuttings. You can take a branch and place it in water and it will very quickly root.
  • Wiring: can be wired but you must be careful the wire does not cut in. Ficus can put on growth quickly and the wire will and bite in.
  • Growing: quite fast growing, especially if given the right conditions.
  • Foliage: evergreen.

Ficus Microcarpa

Ficus Microcarpa
Ficus Microcarpa, also known as Chinese banyan, Malayan banyan, Indian laurel, curtain fig, is a tree in the fig family Moraceae. It is native in a range from China through tropical Asia and the Caroline Islands to Australia.

Ficus Microcarpa is a tropical tree with smooth light-gray bark and entire oblanceolate leaves about 5–6 cm long which in Mediterranean climates grows to about forty feet (twelve meters) tall and with an equal spread of crown. Where conditions are favorable for the banyan habit (tropical and humid subtropical) it grows much larger, producing great numbers of prop roots.

  • Soil: basic Bonsai soil mixture. Akadama mix.
  • Water: this is a plant that naturally thrives in moist, humid climates. In ideal moisture conditions, it would even send out aerial roots, taking on a look similar to that of the banyan tree.
  • Sun: requires a lot of light, preferably full sunlight, so be sure not to place it in a shady location.
  • Hardiness: tropical, indoor tree that does not endure frosty conditions.
  • Fertilizer: every two weeks during summer, and every four weeks during winter if the growth doesn’t stop. Liquid fertilizer can be used as well as organic fertilizer pellets.
  • Repotting: during the spring, every other year.
  • Pruning: has the capacity to sprout new sprigs directly from the bark of the trunk. prune back to 2 leaves after 6-8 leaves have grown. Leaf pruning (defoliation) can be used to reduce leaf size.
  • Propagation: cuttings can be planted at any time of the year, but they have the highest success rate during mid-summer growth. Air-layering will work best during spring, in April through May. In most cases, springtime is the best time for planting Ficus seeds.
  • Wiring: easy due to their flexibility, but you should check the wires regularly as they can cut into the bark very quickly. Strong branches should be shaped with guy-wires because they can be left on the tree for a much longer period.
  • Growing: fast.
  • Foliage: evergreen.

Crassula Ovata “Sunset”

Crassula Ovata

The Jade Tree is an evergreen succulent native to South Africa where it can reach heights of 2 meters or more. In temperate zones Jades are regarded as indoor trees and should not be subjected to temperatures below 5-7 degrees Celsius (41-45 F). The Jade has a thick trunk and branch structure with thick elliptic green succulent leaves. Given sufficient light the leaves develop red edges to their leaves and produce clusters of star-shaped white flowers in Autumn.

  • Soil: well-drained soil.
  • Water: only essential to the plant when the leaves start to develop a wrinkled texture. In winter this can mean watering as little as once every 2-3 weeks.
  • Sun: thrives best in bright light with some direct sunlight. A sunny windowsill will be an ideal position for these plants. They will not flower without sunlight and inadequate light will cause developing spindly growth.
  • Hardiness: prefers ideal room temperatures of around 15.5°C – 24°C/60°F – 75°F.
  • Fertilizer: every two weeks during the growing season, from spring through summer with a balanced fertilizer.
  • Repotting: in spring when the plant becomes root bound or the soil needs renewing. A good solid and heavy pot is best to use because of Jade plants are well known for being top-heavy.
  • Pruning: you can prune the Jades in the early spring because new growth begins during the spring. See the overgrown stems and decide how you want to shape the plant. Use sharp shears to cut overgrown stems and cut out unhealthy branches completely.
  • Propagation: by stem cuttings, leaf cuttings or by basal offsets. The cuttings or offsets should be taken in spring. Take 2-3 inch long stem cuttings and plant it in a 2-3 inch pot of equal parts mixture of peat moss and sand and keep it at normal room temperature in the bright filtered light.
  • Wiring: don’t bother wiring Crassula, it simpler to shape this species by clipping and growing. however, Jades do respond to wiring, setting into new positions within 3-4 weeks depending on the vigor of the specimen. Beware though, as the bark marks very easily and can snap if bent too far.
  • Growing: slowly, about 2 inches a year.

Azalea Japonica

Azalea Japonica
Azalea Japonica, the Japanese azalea, is an evergreen type of azalea with compact growth habit ideal for growing in an acidic soil at the front of a border, in the rock garden or in a container in ericaceous compost. Azaleas are a sub-set of the rhododendron family with smaller-growing with daintier leaves and a denser growth habit than other rhododendrons. Breathtaking blooms in spring and summer are great for attracting wildlife to your garden. Disease resistant but should be kept well watered, especially if grown in a container.

Azaleas have been cultivated for centuries and more than 10,000 vibrant cultivars have been created, which means that there are plenty of options to consider when choosing one of these plants for your garden.

  • Soil: acidic soil mix, Kanuma. The optimal pH is between 5 and 6 for most Azaleas.
  • Water: prefers moist but well drained soil. When Azaleas are subjected to drought, they tend not to flower as well. Since they are shallow-rooted, they do need the soil to be kept moist.
  • Sun: full sun or partial shade.
  • Hardiness: can resist freezing temperatures down to around -15 to 20°C (-4° to 5°F).
  • Fertilizer: to generate spectacular blooming, add heath plant fertilizer.
  • Repotting: it’s best to wait for the blooming to end before repotting. Flowers are very demanding in terms of nutrients, which is why you shouldn’t risk damaging the fragile root system at this time.
  • Pruning: if light pruning is required, this should typically be undertaken just after the end of the flowering period. Make sure you do not prune after buds for next years flowers begin to form as this would mean fewer flowers the following year.
  • Propagation: trim the cut ends of the azalea stem cuttings just below a point of leaf attachment. Remove all leaves from the bottom third of the cutting, and remove all flower buds. Dip the stem end of each cutting in a rooting hormone. Insert the lower one-third of each cutting into the medium.
  • Wiring: Azaleas have a very fine and reactive cambium, which will try to cover the training wire.
  • Growing: they typically grow at a rate of less than 30 cm (12 inches) per year. As they get older, the rate at which their foliage and height grow slows down.