Bamboo Planting And Care
Bamboo is a member of the grass family. Most bamboos are tropical or temperate, from warmer regions of the world. Most Bamboos are evergreen. There are a few semi deciduous types. Bamboos grow from just a few inches tall to 100′ tall. There are two basic types of bamboo, running and clumping. Running types of bamboo send out underground rhizomes from the main plant, upwards to 5′-10′ away, depending on the type and age of the grove. From these rhizomes new culms, or canes, will emerge during the next growing season. When a new culm emerges, it will already be at it’s maximum thickness. New culms grow rapidly once they start to emerge from the rhizome. It is not until it reaches it’s maximum height that it will start to grow branches and leaves. As the branches emerge, the protective sheath around the culm will start to shed itself, often revealing beautiful colors and stripping underneath. There are a few clumping varieties that are an exception to this. Some have culms that will leaf out the second year. Many of the running bamboos can tolerate frost, some can tolerate temperatures well below 0ºf. Clumping types of bamboo send their rhizomes only a few inches away from the main plant. Although some clumping bamboos are very hardy, to temperatures well below 0ºf, many are not and need to be protected from frost and freezing temperatures. The growth cycle of bamboo is some what different than most plants. Rather than dropping its leaves in the fall, as most deciduous plants do, bamboo holds its leaves through the winter. It is not until March or April, when temperatures start to warm and bamboo starts growing again that it loses its leaves. This is a gradual process that takes 4-8 weeks, depending on the variety. As new culms are emerging from the rhizome, older culms will start to shed last years leaves and replace them with new leaves. It is very common to have both older, yellow leaves and newer, green leaves on a culm. In Japan, this is referred to ‘Bamboo autumn’.
Bamboo Planting and Care
Bamboo prefers moist, well drained soils. Most bamboo will not do well in water logged or swampy soil. Good drainage is essential, to avoid root rot. There are some exceptions, such as the Phyllostachys heteroclada . Avoid planting in clay soils when ever possible. Clay soil is generally to compacted for growing and is usually to wet in winter and to dry in summer. Highly compacted or water saturate soils will prevent this. If your soil is heavy clay you should avoid digging out a large hole and planting your bamboo inside of it with potting soils, or other media. This will create a “soup bowl” effect and cause your plant to suffer and possible perish from root rot. It is best to loosen the native soil and plant in it, or mound on top of the clay soil and plant above ground. Not only will mounding keep the roots and rhizomes above the poor soil, it also makes controlling the rhizomes a little easier. All our propagation beds are above ground on mounds. At times bamboo will send rhizomes up slightly, just above the soil, before they go back down into the mounds (see picture below, we’ve cleared away the leaves and compost). It is easy to remove these rhizomes before they start running below ground. This technique should be used along with either root pruning or a barrier. Not all rhizomes behave this way. Some bamboo prefer full sun, others prefer shade. Knowing whether your site is going to have full sun, especially at the hottest part of the day or if it will be in full sun will help to determine which bamboo to purchase.
During the first year you will need to provide your bamboo with an adequate amount of water. What is adequate will depend on factors such as the type of soil you plant in, whether you’ve mulched or not, how much rain you receive, how hot it gets. There is no set amount of water to provide your plant. Bamboo likes a steady amount of water. Water it enough to saturate the root ball. It can dry out a bit, without hurting it. During hot weather dried out bamboo my start to curl its leaves.
Bamboo loves nitrogen. We top dress once a year with a 22% nitrogen fertilizer, then inject weekly with liquid nitrogen and iron. Iron will add a little acid to your soil. Bamboo does prefer slightly acidic soil, usually around a 5.5-6.5 ph. The best time to feed your bamboo is in February or March in cooler climates such as here in the Pacific North West. By late March and early April many of our beds are starting to break winter dormancy, pushing new growth up from below the soil. Manures work great. So do guano’s, corn gluten, blood meal and lawn fertilizers. Avoid fast release chemical lawn fertilizers as they may burn your plants. And remember, compost, compost, compost. Not only will it keep weeds at bay while you establish your plantings, it will also help add organic mater to your soil. Once your grove or hedge is established it may only need a light feeding once a year.
Bamboo does not necessarily need to be pruned. You may want to do a yearly pruning to remove any dead culms or branches. Thinning a grove or hedge will also expose colorful culms. Bamboo can be pruned to a hedge shape, similar to how you would shape a Photinia, Laurel or Privet hedge. True dwarf types of Bamboo can be mowed down on a yearly basis. They will look healthier and more full with a yearly pruning.
Often times we are asked by customers “How many plants do I need to fill in my space?” More often than not it is a matter of ones budget, rather than how many plants it takes. One plant will fill in a large area, if you’re patient. Most bamboo will spread at the rate of about 3′-5′ per year. Planting smaller containers, #1 and #2, at about 4′-5′ on center will help to create a dense grove. Larger sizes can be planted a little further apart. We’ve created general spacing guidelines below. Please remember that these are only guidelines. Your soil, climate, growing conditions, what you feed them as well as irrigation are just some of the factors that will effect your plants growth.
Giant Running Bamboo
#1, #2, #3 containers 4′-5′ o.c.
#5 and #7 containers 5′-10′, o.c.
#15 container 8′-10′, o.c.
Smaller growing bamboo should be planted closer, to fill in faster.
Dwarf bamboo in #1 containers can be planted as close as 12″-18″.
Most clumping bamboo can be planted 5′-8′ apart, o.c.