Sasa, bamboo: planting, cultivation, and uses

Description and Botany

The Sasa is a bamboo that belongs to the Poaceae family (formerly Gramineae). This large family includes other bamboos (Phyllostachys, Fargesia…), herbaceous perennials with more or less fine foliage and elegant habits like Miscanthus, Calamagrostis, or Pennisetum (to name just a few), as well as the “grasses” used to create lawns in our gardens. The Sasa genus is endemic to East Asia, from the southwest of Russia to China, Korea, and Japan. The Japanese origin of its name (“zasa”) refers to its mode of development. The plant, with a woody stump and shallow underground rhizomes, gradually spreads to form large areas. While its growth is less problematic than that of other more invasive bamboos, the Sasa does exhibit a running character that can make it invasive. There are about fifty species, including dwarf varieties, reaching 1 m to 1.2 m (Sasa veitchii) and medium bamboos, which rarely exceed 3 m (Sasa palmata).

The young shoots that emerge from the ground are called turions, and some varieties are prepared in salads for their taste value, such as Sasa palmata ‘Nebulosa’. These turions then develop into fine, rigid yet flexible canes, known as culms. Cylindrical, they are smooth and pruinose, or covered in hairs (Sasa Veitchii). Their colour ranges from pale green to olive green, sometimes tinged with purple or nearly black shades at ripeness. In Sasa kurilensis, the young culms exhibit an original curvature, which they lose as they develop. The foliage, dense and evergreen, consists of large oblong leaves, some of which can measure up to 60 cm long, giving it a most exotic and exuberant appearance. Often with slightly dentate edges, they tend to dry at their edges due to the cold, but this characteristic does not detract from their aesthetic appeal. Instead of appearing dry or unhealthy, the leaves look variegated. The exotic effect of the plant and its graphic form sometimes resemble that of a palm tree. In some species, like Sasa kurilensis, the young foliage can be twice as large as that on mature canes.

The plant ultimately forms a dense and opulent bush, making it an excellent candidate for creating large patches in Japanese-style landscaping. The Sasa can also form low hedges along paths or walkways, and it responds very well to pruning, which even encourages a more lush foliage. However, it is essential to choose its planting location carefully and avoid pairing it with weak neighbours, particularly herbaceous plants, which it could quickly smother. In any case, using a rhizome barrier is the wisest solution to enjoy this bamboo. When well used, it allows for the creation of original displays with accents from distant lands. It can thus be associated with large trees, gracefully dressing their bases.

The flowering of Sasa, like that of all bamboos, is very rare. Insignificant from an aesthetic point of view, it is either sporadic or gregarious, and signifies the death of the affected plants.

Not fussy about soil type, it is more comfortable in soils that retain good moisture during the season, but where water does not stagnate in winter. This bamboo, hardy below -15°C, grows in both sun and shade, under the cover of large bushes or trees, for example. It can also be grown in pots, to bring a zen, elegant, and natural touch to a balcony or terrace.

Sasa palmata ‘Nebulosa’ and Sasa kurilensis (photo Tatters)

The different varieties of Sasa

Sasa veitchii

A dwarf but running variety, with stunning dark green foliage and light margins in winter. Ideal for enhancing the edges of water features.

• Height at maturity 1,20 m

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Sasa tsuboiana Pseudosasa japonica

A small variety with semi-evergreen dark green foliage and purple-tinted canes. Slightly running, it is perfect for small gardens or pot cultivation.

• Height at maturity 1,50 m

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Sasa tessellata

A small bamboo that forms a dense dark green bush. Slightly running, it is fast-growing and offers the largest foliage of the genus.

• Height at maturity 1,50 m

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Sasa palmata Nebulosa - Dwarf Bamboo

A medium bamboo with green foliage supported by stems that blacken with age.

• Height at maturity 2,50 m

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Sasa kurilensis

Its young leaves are almost twice as wide as the old ones. Very hardy, it tolerates full sun well but spreads vigorously.

• Height at maturity 2,50 m

See the full description

Planting

Where to Plant Sasa?

Highly adaptable, Sasa thrives in heavy, clayey soil or lighter, well-drained soil, as long as it remains moist in summer. Bamboos are indeed plants that require water to develop properly.

Due to its expansive character, it is important to choose the location of your Sasa carefully. Avoid planting it directly in the ground without first installing a rhizome barrier. Made from composite materials, this is a thick membrane that helps keep the roots in check. As the rhizomes develop on the surface, it is necessary to let the barrier extend slightly above ground so that your bamboo cannot step over it. You can then disguise it by camouflaging it with plants that you place around the perimeter. Perfectly hardy, Sasa can be planted in non-burning sunlight or in shade, as long as it has access to cool soil. Its habit and broad leaves provide a graphic quality that works wonders in Asian-style landscaping, but it is equally suitable for contemporary-inspired gardens and does not look out of place in more natural or wild gardens. In any case, it adds a pronounced exotic touch and contributes to the impression of opulence in your plantings.

Depending on your desires, you can use it to create small hedges or screens, for example, to create different green rooms. They can also dress the base of trees and shrubs or line paved paths to soften their rigidity.

Finally, with regular watering, Sasa can enhance a terrace, balcony, or patio if you grow it in a pot. Small city gardens can thus accommodate it and transform into true little oases, with an atmosphere that never fails to impress.

Sasa veitchii (photo Carl Lewis – FlickR)

When to Plant?

While it is theoretically possible to plant potted plants all year round, the ideal period is between late summer and autumn, once the heat has passed. In regions with cold, wet winters, you may prefer early spring. In any case, be sure not to let the potting soil dry out.

How to Plant?

Planting in the Ground:

1. Determine in advance the location where you wish to install your Sasa. This could be a round or organically shaped bed, or a border. The dimensions depend on the space you have and your landscaping project. Although this bamboo spreads on its own, feel free to plant several young plants if the area is large, so that they can fill the space more quickly.
2. Dig a deep hole (at least the height of the root ball) and thoroughly loosen the soil.
3. Add well-decomposed manure and crushed horn (follow the dosages indicated on the packaging). In heavy, compact soil, amend with potting soil.
4. Install a rhizome barrier (also called a root barrier) around the perimeter. About sixty centimetres high, it comes in various lengths according to your needs. Bury the barrier leaving it protruding 5 to 7 cm above the ground.
5. Place your young plants, lightly firm the soil, and water generously (up to 10 litres per plant).
6. Over time, the fallen leaves will create a natural mulch, but initially, it is good to cover the surface with a mulch of your choice (mineral or organic depending on the desired effect).
7. Monitor watering in the first few months, and remain vigilant to ensure your bamboo never lacks water. Leaves that curl and shrivel should alert you).

Planting in a Pot:

1. Choose a pot of good dimensions (minimum 50 cm in all directions).
2. Use a rich and substantial substrate (good quality potting soil mixed with garden soil, for example) to which you add one or two handfuls of crushed horn. A bit of decomposed manure also provides the necessary nutrients for harmonious growth. It is available in the form of dehydrated granules, easy to store and use.
3. Fill your container with your substrate, then place your plant in the centre.
4. Top up and water to moisten all the potting soil.
5. Mulch with the material of your choice.
6. Never let the substrate dry out. In season, you can place a saucer under the pot if its dimensions allow.

Maintenance and Care

Bamboos are plants that require very little care.

• The main thing to watch for is not to let them suffer from drought. Regular watering is therefore necessary during the season, especially with the dry spells that our gardens are increasingly facing.
• In pots, the substrate dries out even faster. Watering must therefore be even more of a focus for you.
• Every year, at the beginning of spring, you can add compost, dehydrated manure, or ground horn, all of which will nourish the plant in the long term.
• Regularly maintain or replenish the mulch until the bamboo leaves form a sufficient carpet.
• Bamboos can grow without needing pruning, but Sasa responds very well to this operation, which should be done at the end of winter, before the young shoots appear. This helps keep them at the desired height (especially if you are using them as a hedge) and gives them a more regular shape, while encouraging the growth of new, larger, and more lush leaves.
• In winter, the edges of the leaves may dry out, giving the plant a decorative variegated appearance.
• Remember to regularly cut the dried canes at the base. This promotes the growth of new canes and the regeneration of the plant.

Multiplication

As with many of its cousins, the Sasa spreads its rootstock around the periphery. Its propagation is therefore easy, by taking peripheral clumps. Intervene between the end of winter and the beginning of spring.

1. Choose a mature and well-developed young plant.
2. If the soil seems dry, water generously the day before the intervention.
3. Using a sharp spade, cut one or more clumps from the periphery of the root ball and remove them from the ground.
4. Each clump should have several canes (at least 3 to 5) and roots.
5. Replant immediately in the desired location, following the same procedure as for a standard planting.

For plants grown in containers, remove from the pot and divide the root ball into several clumps, following the same principle.

Associate Sasa with the garden

Sasa can seem difficult to pair. It is true that their root system leaves little chance for more discreet neighbours. By using a root barrier, it is easy to circumvent the problem.

• In an Asian-inspired garden, pair them with taller bamboos such as Phyllostachys or Fargesias (the latter do not sucker and thus remain well-behaved). Azaleas, conifers (some of which can adopt the ‘Niwaki’ style and be pruned into clouds), Japanese maples, camellias, nandina, Chinese palms or Pieris are all renowned for their use in such arrangements. For perennials, consider Hosta, Hakonechloa, ferns, Rodgersia or Ophiopogons, which allow for beautiful plays on shapes, textures, and foliage colours.
• In a woodland setting, Sasa can dress the base of trees or shrubs that can support their vigour, such as Metasequoia or Cryptomeria. Guaranteed change of scenery!
• For a more contemporary atmosphere, Cycas, horsetails, birches, ornamental alliums, Mahonia or even grasses can be combined in graphic arrangements.

Asian inspiration: Rodgersia pinnata ‘Chocolate Wings’, Sasa veitchii (photo Plant Image Library), Rhododendron ‘Amoena’, Acer palmatum ‘Atropurpureum’, Nandina domestica ‘Gulf Stream’ and Fargesia rufa