What you need to know:
- Bamboo is one of the fastest-growing plants in the world; with a new shoot attaining full height and diameter in 60 -90 days (two to three months)
- A bamboo plant or clump has an extensive root system that continually sends up new shoots.
- Planting runner bamboo without management strategy is what has given bamboo a bad reputation among farmers in Uganda, especially those with small plots of land.
There is a surge in demand for bamboo planting material in Uganda. Farmers are keen to cash in on bamboo, the “new kid on the block”, which has earned itself a reputation worldwide as a versatile renewable resource.
The shortage of planting material is only rivalled by lack of basic information. There is a need to separate myths from facts about bamboo growing.
As we prepare to mark World Bamboo Day on September 18, here is basic information that any aspiring bamboo farmer should have at their fingertips.
Bamboo is one of the fastest-growing plants in the world; with a new shoot attaining full height and diameter in 60 -90 days (two to three months). Some species can grow up to 120 centimetres in a day.
After reaching full height, it ceases to grow; not increase in size, but only stronger.
A bamboo plant or clump has an extensive root system that continually sends up new shoots. This takes a lot of energy. Both runner and clumping bamboos store energy in their rhizome systems to produce new shoots.
As new culms, or poles, or stems, they produce branches and leaves, which send energy back to the rhizome system to produce more shoots, and continue to harden and mature for several years. Individual culms may live as long as 20 years.
Their hollow segmented structure gives them a combination of strength, flexibility and lightness.
Bamboo a grass
Bamboo is grass with tree-like properties, which make it a perfect alternative. It is a rhizomatous plant, just like ginger, which farmers in Uganda are more familiar with.
It grows principally from rhizomes: tough underground stems that produce roots, new shoots and more rhizomes.
Many Ugandan farmers fear to plant bamboo because it will “steal” or “grab” their land. They could be right. They could be wrong. It depends on the type. There are about 1,200 species in the world, broadly categorized into runner and clumping bamboo.
Clumping bamboo’s short slow-spreading rhizomes is non-invasive. The rhizomes are short and new shoots appear close to the mother culms in a predictable fashion.
The new shoots grow at the end of each rhizome and so the outer poles or stems mark the limit of the hard underground parts of the plant.
For most species, the clump size is self limiting and will not continue to increase indefinitely. It is possible to control the shape and size of clumps by cutting the shoots where they are not wanted.
Runner bamboo with long fast-spreading rhizomes can be invasive, especially in tropical conditions.
The rhizomes are long and adventurous like those of Couch or Kikuyu grass. This type should only be planted where there is plenty of space and the farmer should have a strategy on how to manage it.
Planting runner bamboo without management strategy is what has given bamboo a bad reputation among farmers in Uganda, especially those with small plots of land. Yet some of the best species for timber production, including the popular Moso, are of the runner type.
Farmers in Uganda will do everything to protect their land, but then neglect their soils, which are washed away during heavy rains.
Soil erosion, as a result of reckless clearing of vegetation cover, is a challenges facing farmers in Uganda. Bamboo has long, fibrous, shallow growing roots that are able to stabilise soil and prevent erosion. People living in mountainous areas like Rwenzori and Elgon should plant bamboo to protect their soils.
Bamboo flowers and dies. Some species never or rarely flower. Others flower sporadically. Length of the flowering cycle varies considerably, some can take up to 120 years, while others flower almost annually and not die back at all.
Bamboo is an adaptable plant. Not only has it managed to evolve into such varied forms to suit diverse environments, its size and development can also vary within individuals of the same species growing in different conditions. You can find technical descriptions with incredibly large height ranges specified.
Bamboo is propagated by taking pieces and keeping them under conditions that stimulate them to grow.
Some species are easy to propagate, others less so. A number of research institutions and individual nursery operators in Uganda are experimenting with different techniques to find the most suitable for different species.
It is important to select mature plants that are pest- and disease-free for propagation.
Careful balance of moisture and drainage, and high humidity are essential for good results in all species. Warmth and good light are also required.
Basic propagation techniques
Offsets: Bamboo plants growing in pots or in the ground can be divided to produce new plants. The idea is to divide the underground system of rhizomes and roots into ‘offsets’ of one or more culms. A sharp saw or panga can be used.
A single culm (stem) with healthy rhizome and buds is enough to generate a new clump (plant). However removing too many offsets from the mother plant can damage it, because bamboo stores much of its energy (food) in rhizomes and lower culms.
Cuttings: Some species can be propagated from cuttings. Single node cuttings can be placed straight into pots, but this takes a lot of skill and care. Better results are achieved in a controlled environment such as in a greenhouse.
Layering: Bamboo culms can be pulled down to the ground and covered with soil and mulch and new plants will form at the nodes.
This is the easiest and most reliable way to propagate from layerings. By leaving the culm attached to the parent plant, minimum care is required, but it takes a long time, one or two years for some species, to form plants strong enough to be transplanted.
Alternatively, the culm (with or without the rhizome), can be removed from the plant and layered in a nursery. This can produce new plants fast but requires more intense care.
Seed: It is possible to propagate bamboo from seed. However, seeds are rare since bamboo flowering is also rare, and the seeds need to be planted as soon as possible, as they lose viability fast.
Plantlets propagated from seed tend to be delicate, and so need to be kept longer in the nursery, sometimes up to a year.