Cryptomeria meaning “hidden parts” is a monotypic conifer genus. It belongs to the family of cypress Cupressaceae. Formerly, it belonged to the Taxodiaceae family. The Cryptomeria genus includes a single species known as the Cryptomeria Japonica. This large coniferous tree is known as Sugi in Japan and is loved in the country. The tree is also called the Japanese Cedar or Japanese Redwood. The cool and moist regions of Japan and China are ideal for the growth of this tree.
Cryptomeria is a big evergreen tree – it can reach up to 70 m (230 ft) in height with a 4 m (13 ft) trunk diameter. It can spread to about 20 feet into an irregular and narrow oval form. A pronounced characteristic of the older trees is the presence of dark brown ornamental bark which peels off in vertical stripes.
The leaves of the Cryptomeria Sugi are needle-like and arranged spirally. Their length is around 0.5–1 cm (1⁄4–3⁄8in), having globular seed cones of 1–2 cm (1⁄2–3⁄4in) diameter and about 20–40 scales. The color of the foliage turns an impressive olive, red, brown, or purple during autumn and winter. Come spring, the foliage again turns green. The tree branches usually remain erect. The branches of the older specimens hang toward the ground.
The Cryptomeria can be distinguished as the Japanese and Chinese variety. The Chinese variety has longer needled leaves and approximately 50 cultivars. When it comes to bonsai, the Japanese variety is the more popular one. Japanese Sugi is a quite popular bonsai and is suitable for small shohin bonsai. The Cryptomeria Sugi can be fashioned in a variety of bonsai styles – formal and informal uprights, with occasional twin trunks, root over rocks, or clasped to a rock planting.
This guide is an attempt to acquaint advanced bonsai enthusiasts with Cryptomeria Sugi Bonsai Tree care.
How long does it take to grow Cryptomeria (Sugi) Bonsai?
The Cryptomeria (Sugi) is a slow-growing tree. It generally grows 12 inches or 1 foot in height per growing season. So, in 20 years it can reach a height of around 20 feet. These coniferous trees are capable of achieving a full height of 50 to 80 feet. There are also instances of 100 feet tall trees. So it is apt to define Cryptomeria Sugi as a very slow-growing huge species of tree. However, some cultivars can grow more quickly. “Sekkan-sugi,” is one such variety that can grow 24 inches or more in a single season.
Now you know how long and how big a Cryptomeria (Sugi) bonsai can grow. We can now discuss the basics concerning the best climatic conditions, soil requirements, and other ways to take care of the Cryptomeria (Sugi) bonsai tree.
Position and lighting
Cryptomeria (Sugi) bonsai requires full sun but it should not be scorching heat. During hot summer months, it is best to place them in semi-shaded areas. They can tolerate a bit of frost. So during the winter months, a cold yet frost-free greenhouse works best for them.
Cryptomeria (Sugi) bonsai shows a preference towards moist and humid climatic conditions with full sun exposure. They are typically hardy when grown in USDA growing zones between 5 and 8. When kept outside during winter, the foliage generally turns reddish or brown. But, they recover and get back their green leaves during spring. They need protection from strong winds.
Fertile deep loamy soil, which can retain moisture, in a semi-shaded area is ideal for the Cryptomeria (Sugi) species of bonsai. The soil should be moist but also well-drained. It can grow in acid, neutral and alkaline soils. The preferred pH value is between 5.5 to 7, which means it prefers slightly acidic or neutral soils.
The Cryptomeria (Sugi) bonsai needs abundant water during the growing season. Water the plant regularly so that the rootball remains moist. You can also increase the humidity by misting over the foliage, bench, and ground below. Without enough humidity, it tends to lose its needles.
Feeding is essential to make sure your Cryptomeria (Sugi) species of bonsai can grow. Feeding must typically be done during the growing season – from spring to autumn. You can fertilize the tree with both solid and liquid fertilizers. Use solid organic fertilizer once a month and liquid fertilizer once a week during the growing period.
The art of Japanese Bonsai is to create a smaller ornamental version of big beautiful trees. They look impressive and can grow in a variety of styles. There are medium and large-sized bonsai trees. The Cryptomeria (Sugi) is a versatile tree and can be fashioned in a range of bonsai styles. It can be styled formal and informal uprights, with occasional twin trunks, with roots over rocks, or clasped to rock plantings.
How to Plant and Grow Cryptomeria (Sugi) Bonsai?
You want to know how to plant and grow Cryptomeria (Sugi) bonsai? That’s great! But first, let us get an idea about the popular cultivars which are commonly used:
Cryptomeria japonica ‘Jindai-sugi’: it is a compact, conical Cryptomeria
Cryptomeria japonica ‘Lobbi Nana’:it is a bushy, rounded dwarf Cryptomeria
Cryptomeria japonica ‘Ryokogu Coyokyo’: compact, dense, and mound-forming dwarf Cryptomeria
Cryptomeria japonica ‘Sekkan Sugi’: it is a bushy, compact, and conical Cryptomeria bonsai
Cryptomeria japonica ‘Bandai Sugi’: it is slow-growing with very dense needle-like foliage. It can grow up to 6 feet tall.
Now that you know about the popular Cryptomeria (Sugi) bonsai cultivars, let us dig deep into the specifics of how you can actually plant and grow them. The first thing to keep in mind is that you should plant your out pot specimens during spring.
Cryptomeria seeds are relatively easy to germinate and grow. A short cold stratification period in the fridge can easily break the dormancy of the seeds. To start with, you need to soak the seeds in water for 24 hours. Drain off the water fully, put them in a zip-lock freezer bag and keep it in the fridge. It will take around 4 to 6 weeks for the seeds to get ready to be sown. Things to keep in mind during those weeks are:
- Do not let the seeds completely dry out or get waterlogged
- Check the seeds every week
You can also incorporate a little damp vermiculite or perlite while starting treatment to help them retain moisture without getting waterlogged.
Now fill your plant container with good quality potting compost. You can use plant pots, seed trays, plug trays, or even DIY containers with drainage holes. Firm the compost, sow the seeds on the surface, cover the seeds with a few millimeters of vermiculite or a thin layer of sieved compost. Gently water the soil and keep them at room temperature. Germination will start within a few weeks of sowing.
The seedlings generally grow between 5 to 10 cm in height in the first growing season. The growth of robust, trouble-free seedlings depends on sowing time and cultivation techniques. Position the pot in full sun, water it regularly and keep it free of other weeds. The growth of the trees accelerates in the second and subsequent years after which they can be planted in their permanent position.
Propagation of Cryptomeria (Sugi) bonsai species can be done with the help of simple layering, or softwood cuttings in the summer months. This bonsai tree can also be propagated from seed in spring. Take professional help while getting it grafted.
Pruning and wiring
During the growing season, once the new shoots reach 1 to 2cm long, you should pinch back the new growth. This process helps in developing and maintaining compact foliage pads. The onset of spring is perfect to engage yourself in some bonsai pruning. Keep the undersides and the bases of the branches clean by removing excess shoots and old foliage. This will help light and air reach the desired foliage which in turn will reduce the likelihood of fungus and insect problems.
The intersection between the trunk and branches tends to get thick. Unwanted upper branches should be removed quickly so that trunk paper loss remains minimal. The delicate Cryptomeria should be pampered heavily after pruning and wiring. Protect it from sun and wind, and keep it moist for a few weeks after pruning and wiring.
The younger trees, after they start growing, should be repotted every 3 – 5 years in spring. A well-drained soil mixture should be used for repotting the trees. As the roots of the Cryptomeria grow very slowly, pruning them should also be very gradual and light.
How to Care for Your Cryptomeria (Sugi) Bonsai?
The Cryptomeria bonsai will need your constant attention and care. You need to prune it around 3 to 4 times a year so that the foliage does not become unruly. A simple cut wound can turn this bonsai brown. However, new foliage growth can hide those brown spots. Pruning the brown foliage also gives the tree a healthy appearance. Don’t feel sad while cutting the brown shoots as they tend to bud back from really old wood.
The Cryptomeria (Sugi) bonsai loves humidity and full sun. So, it is imperative to keep the bonsai in an ideal sunny and moisture-laden place. They tend to suffer from dry heat as well as too much frost.
Pests and diseases
Cryptomeria trees are not prone to attack by pests and diseases. Mites, mildew, or scale can at times infest the foliage. You can use specific pesticides to treat pests and diseases.