As far as the space requirement of the giant bamboo is concerned, no less than 10 m² should be planned. Depending on the variety, even more than 20 m² can be required in old age. Various types of giant bamboo are available in stores, which can reach different heights. In the garden, the giant bamboo, of which most species are frost-resistant to at least – 15 degrees, is very good as a hedge or privacy screen. All Phyllosrachys species need a rhizome barrier because they form underground runners that spread very widely. The bamboo stalks develop from these rhizomes and, without a root barrier, can sometimes appear several meters away from the actual mother plant. A root barrier is particularly necessary if the bamboo is to be planted close to a neighboring property.
Table of Contents
planting
Before planting, the soil should be loosened over a large area so that the plant can form new roots relatively quickly. Container or top plants should be watered thoroughly before planting. To do this, the root ball is placed in a vessel with water until no more air bubbles rise.
In the meantime, a pit at least 15 m² in size and at least 60 cm, better 100 cm deep, is dug, if necessary with a mini excavator. Then, depending on the size, the pit is lined with a 60 or 100 cm wide rhizome sheet, ie it is placed vertically or on edge in the pit. It should look about 3-5 cm out of the pit so that the roots cannot climb over the foil. Where the foil overlaps, it should be closed with an aluminum rail, for example, so that the roots cannot push through the foil at this point.
Then the pit is filled with earth and the giant bamboo is planted. The plant should ultimately be about 10 cm below the upper edge of the foil, as the root area will rise over the years. Finally, it is thoroughly watered. In order not to let the bamboo grow uncontrollably, it is advisable to regularly cut old and thin bamboo stalks just above the ground. Things to note when planting
- The roots of all Phyllostachys species spread out very strongly.
- Accordingly, a so-called rhizome barrier should definitely be introduced.
- If you want to do without it, it is usually hardly possible to keep this bamboo in check.
- The subsequent introduction of a root barrier is extremely laborious and sometimes hardly possible.
- When planting, care should be taken to ensure that there is sufficient distance from other plants as well as buildings.
- This is also important because giant bamboo can live between 20 and 30 years.
- Rhizome barriers made of special foil are available in stores.
Spring planting
A giant bamboo in a pot or container is best planted in spring so that it has enough time to grow before the first frost. By the summer it should have grown so well that it can cope with less water.
Planting in summer
Planting in summer, between May and August, is usually also possible, but not recommended. Since it can get very hot and dry in May and if the roots are not anchored deep enough in the ground, drought damage can easily occur. To prevent this, additional watering is required so that the bamboo can develop well during this time.
Autumn planting
Autumn is also still suitable for planting, because the soil is usually still warm enough in September and the temperatures in October are often still relatively mild. In late autumn there should be no more planting if possible, and if so, then only with sufficient winter protection.
Location and soil
Depending on the species, giant bamboo prefers sunny or partially shaded locations that should be protected from both winter sun and cold winds. However, the right location should also be selected according to the space requirements of the respective giant bamboo. The soil should be loose and well-drained, rich in nutrients and slightly moist. If the soil quality is not optimal, it can be improved by adding peat humus during planting. Heavy, impermeable soils, which tend to become waterlogged, can be upgraded by incorporating perlite or sand, thereby increasing the drainage capacity.
Water
The first time the root ball is watered before planting. Then it is generously watered or washed in immediately after planting. This should make possible air inclusions in the ground disappear. This is especially advisable when planting in summer.
Bamboo is an evergreen plant, which means that it needs water all year round and therefore needs to be watered in winter too. Otherwise, giant bamboo should be watered thoroughly when it is dry, warm and hot and before long periods of frost.
In order to keep evaporation as low as possible in summer, water should only be watered early in the morning or in the evening during this time. Despite the high water requirement, waterlogging should be avoided at all costs, as this would lead to the death of the plant.
Fertilize
- The best fertilizer for giant bamboo and generally for bamboo is well-deposited horse manure.
- This is due to the high nitrogen content.
- However, commercially available bamboo fertilizers can also be used.
- As a rule, these are slow-release fertilizers.
- This should be administered for the first time in spring and for the last time in July.
- The manufacturer’s instructions for use must be observed.
Overwinter
Even if most types of giant bamboo are relatively hardy, the root area should be covered with straw or dry leaves in the first few years, especially in particularly cold regions. To protect the young stalks, we recommend a mat made of thatch, bast or fleece, with which the stalks are wrapped.
Such winter protection is also recommended for locations that are exposed to the winter sun during long periods of frost. This is to avoid drying out or drying damage. This is no longer necessary for older copies.
Snow on the root area should definitely be left as it forms a very good insulation layer. Only the wet snow should be shaken off the bamboo stalks to avoid snow breakage.
Multiplication
Sowing
giant bamboo can be propagated vegetatively via rhizome parts or division or generatively via seeds. Sowing is relatively easy and can be done indoors all year round. The grain-like seeds are placed in coconut fiber or commercially available potting soil, lightly pressed and not covered with soil, as this is a light germination.
Now the whole thing has to be kept slightly moist and placed in a light and warm place at temperatures of approx. 25 degrees. In order to guarantee such temperatures, for example, a greenhouse or a cover of the planter with cling film can be used. Under these conditions the seeds will germinate within 1-3 weeks.
Rhizome
In the case of runners-forming bamboo species, which also include the genus Phyllostachys, propagation can also take place via pieces of rhizome. This form of propagation is the easiest and fastest method and can be done in spring and winter.
For this purpose, mature rhizomes are cut into individual pieces. These should consist of at least one internode, each with two eyes. The internode is the leafless part of a stem axis that is located between two nodes.
These rhizome pieces are then individually placed 5 cm deep in the permeable substrate in larger pots. Now the whole thing should ideally be placed in a foil or greenhouse. After about 2-3 years, decorative plants should have developed.
Division
Propagation by division is also possible, but quite difficult, especially with older plants. For this, parts of the root ball are required, which are separated from the plant with a sharp spade or an ax with a stalk. The separated sections are then planted in their final location. To make it easier for the plant to grow, about 30% of the leaf mass should be removed. If necessary, a support can be attached initially for stabilization.
cut
Bamboo must be thinned regularly, ie the number of stalks should be limited by repeatedly cutting stalks on the ground. In this way, uncontrolled wild growth or spread can be contained quite well. If the bamboo is a bit too big, you can primarily cut out the largest stalks.
Diseases
Diseases are actually not to be feared with the giant bamboo, but damage can occur due to drought or over-fertilization. Giant bamboo is also relatively safe from pests. In exceptional cases, however, an infestation with the bamboo mite can occur. This lives in colonies on the underside of the leaf, protected by a web. Fully systemic acaricides based on Tebufenpyrad or Dimethoat, which are very effective, can be used for control.
Popular varieties for the garden
- Phyllostachys ‘pubescens and edulis’ – The varieties ‘pubescens’ and ‘edulis’ are frost hardy up to a maximum of – 15 degrees and reach a height of up to 10 meters. Their stalks can have a diameter of up to 15 cm.
- Phyllostachys bissetii – This bamboo species is the hardest in winter among the Phyllostachys species. It can withstand temperatures of up to – 25 degrees. It reaches heights of up to 7 m. Bamboo shoots are made from the young shoots of these varieties. This variety is very suitable as a privacy and wind protection plant.
- Phyllostachys vivax ‘Aureocaulis’ – This strongly overgrown variety produces particularly beautiful stalks with a diameter of 6 cm. These are initially pale yellow and later yellow to orange with green stripes. It grows to a height of between 6 and 12 m and is hardy to -22 degrees.
- Phyllostachys iridescens – This giant bamboo grows up to 10 m high, with a stem diameter of up to 8 cm. It is hardy to -20 degrees. Some of the stalks have yellow stripes and often have slight curves in the lower area.
- Phyllostachys nigra ‘Boryana’ – A very robust variety that is particularly suitable for cold winter regions. In sheltered places it can reach heights of up to 12 m. The stalks are up to 6 cm thick, are initially green and from the second year they are spotted black. In winter it can withstand temperatures of up to – 20 degrees.
Conclusion
Giant bamboo, especially the Phyllostachys species, can be very decorative, even if in our latitudes it does not even come close to the stature heights that are typical in its original home. However, giant bamboo is usually a stolon-forming species for which a rhizome barrier is essential, which ideally should be created when planting.
