Clay soil is amazing earth with plenty of nutrients that can help your bamboo thrive. It actually can be very fertile but you might have to do some work. Working with heavy soil can become a nightmare when you begin to battle with compactness and drainage problems.
While most bamboo species prefer well-draining loam soil, certain species do well in clay. Mostly, these bamboo species tolerate wet conditions that are prevalent in clay soil. Water Bamboo, Black Bamboo, Rufa, and Umbrella Bamboo are a few of those capable species that do fine with clay soil.
Heavy soils hold on to water and take really long to warm up in summer. This can become a huge problem for gardeners. Don’t worry! You can do something about it. You can improve your clay soil and even accommodate other bamboo species. I’ll teach you how you can achieve this.
Do you want to jump ahead?
Firstly, what is clay soil?
Clay soil is often referred to as heavy soil. Regular soil is composed of minerals, organic matter, living organisms, gas, and water. Silt, sand, and clay are soil minerals, and depending on the ratio you’ll have different soil textures. If soil has 30% (or more) clay particles, it’s clay soil or heavy soil.
Clay has very small particles. In fact, they are the smallest soil grains (sand being the largest). On top of that, the grains are flat as well. As a result, they can stack tightly so there’s little or no air space between particles. This means that clay soil hardly drains and it holds on to water longer.
Although clay soil is the densest and heaviest type of soil, it is very rich in plant nutrients. However, it doesn’t have much organic matter.
What is heavy clay soil?
Heavy clay soil is a soil that consists of more than 50% fine clay particles. Heavy clay soil is usually hard to manage, especially when wet. If you have heavy clay soil, you may want to work in some organic matter to make it easier to manage. You may have to wait for a drought in order to work this soil, otherwise, it will be too sticky and heavy.
How to identify that you have clay soil in your garden
Chances are high that you know already what type of soil you have. Just in case you are not sure, you can do some simple tests to determine if you’ve got clay.
Generally, these are the characteristics of clay:
- Sticky texture: It’ll stick to your garden shoes and tools.
- Fine particles: Take a bit between fingers and rub it. It should feel very smooth.
- You have clay if your soil forms clods that are hard to separate when wet.
- You often have puddles for a long time.
- If your soil retains water, it’s likely that your soil consists of more clay.
If you are now sure that you’ve actually got clay soil. Let’s check out the advantages and disadvantages of this soil type.
Is heavy soil good or bad for growing bamboo?
Generally speaking, bamboo loves loam soil, which is well-balanced in minerals, organic matter, etc. However, this doesn’t mean that clay soil is absolutely bad for bamboo.
Advantages of clay soil
Clay soil is richer in nutrients than other types of soil
Due to the density of this soil, it is able to hold on to nutrients for a longer time. These are very good for plants. Clay particles are usually negatively charged, so they can attract and hold positively charged particles like potassium, magnesium, and calcium which is very good for your bamboo.
Clay retains moisture
No matter what bamboo, they all like water. Certain bamboo plants need even more water, for example, Phyllostachys Heteroclada Purpurata ‘Water bamboo’. Clay soil retains water greatly due to its density.
Disadvantages of clay soil
Drainage issues
The density of clay soil causes water to stand on top after heavy rainfall. This is something that bamboo plants don’t like. They prefer well-draining soil.
Clay soil compacts easily
This reduces the air space in the soil making it very hard for young and delicate plants to grow. However, bamboo is quite a strong grower as it develops rhizomes or clumpers. Therefore, you may just find your plants to spread a little slower.
Tends to be alkaline in pH
Generally, bamboos prefer slightly acidic soil. The fact that clay soil tends to be alkaline is another disadvantage.
What bamboo grows well in clay soil?
Generally, bamboo plants prefer well-aerated and slightly acidic soil. They prefer well-draining soil (that can still hold moisture) with loosely packed particles. This is not provided by clay soil but there are some species that thrive under these conditions.
For instance, Phyllostachys thrives in loose, well-drained soil that is rich in organic matter. Yet, many of this genus tolerate heavy clay soils.
Let’s have a closer look at a few bamboos that grow well in clay soil.
Phyllostachys heteroclada ‘Water bamboo’
- Type: Running
- Height: 30 ft (9 m)
- Stem diameter: 2 in (5 cm)
- USDA zones: 6b-10
- Hardiness: (-10°F / -23°C)
- Light: Full sun, part sun
- Watering: Regular
Just as the name implies, this bamboo species can thrive in very wet soil conditions. Phyllostachys heteroclada can even survive standing water. This is due to the fact that the culms and roots of this bamboo have hollow air channels.
In fact, Water Bamboo grows very well in soil that other bamboo would not survive in. It has beautiful straight canes that usually turn into a grey-green color when mature. This hardy running bamboo will make a wonderful privacy screen or grove.
Phyllostachys nigra ‘Black Bamboo’
- Type: Running
- Height: 20-35 ft (6-10.5 m)
- Stem diameter: 2.25 in (5.7 cm)
- USDA zones: 7-10
- Hardiness: (5°F / -15°C)
- Light: Full sun, part shade
- Watering: Regular
This elegant bamboo has bright green culms that later turn black when mature. This is why it’s commonly called Black Bamboo. It doesn’t turn dark at once. You will see spots that spread over the years. It may take around 3 years to develop completely black culm. They also have alternating grooves on the internodes.
It’s a running bamboo that tolerates heavy clay soil. It may not grow as fast as others initially but can spread a lot later if the conditions are right. It’s hardy to USDA zones 7-10 and not as hardy as other species. It can grow in partial shade and it prefers moist soil.
Phyllostachys aurea ‘Holochrysa’
- Type: Running
- Height: 15-30 ft (4.5-9 m)
- Stem diameter: 1.25 in (3 cm)
- USDA zones: 7a-10
- Hardiness: (0°F / -18°C)
- Light: Full sun, part shade
- Watering: High
A fast-growing bamboo with pale green culms that turns gold at maturity. It is a cultivar of Golden Bamboo (Phyllostachys aurea) and truly is a golden plant. The culms turn yellow or orange-gold quickly. It also features distorted irregular bubbly nodes.
This bamboo grows better in full sun and is suitable for heavy clay soil. It is tolerant of both moist and drought conditions. The color is not changing because of sun exposure, so you don’t have to worry about it.
Any Phyllostachys aurea is a fast spreading plant that is invasive. You should definitely install barriers to confine it.
Fargesia robusta ‘Campbell’
- Type: Clumping
- Height: 12-15 ft (3.5-4 m)
- Stem diameter: 0.75 in (1.9 cm)
- USDA zones: 7-9
- Hardiness: (0°F / -18°C)
- Light: Full sun, part shade
- Watering: High
Campbell is one of the tallest Fargesias. It’s a very versatile bamboo plant. It is tolerant of a wide range of soil conditions. It has slender upright culms that are very beautiful for screens and hedges. They are green with cream-white long-lasting sheaths. This gives it a checkered look.
It’s a fast-growing plant with non-invasive habits. So, you don’t have to worry about the spread. It’ll grow in a circular fashion shooting out new culms from the main clump. You can plant it in the garden or in a pot just around your patio.
Fargesia nitida ‘Fountain Bamboo’
- Type: Clumping
- Height: 10-12 ft (3-3.5 m)
- Stem diameter: 0.75 in (1.9 cm)
- USDA zones: 5-9
- Hardiness: (-20°F / -29°C)
- Light: Part shade, complete shade
- Watering: Average
This species is also known as Fountain Bamboo. It is an evergreen bamboo with green-purplish canes and small dark green leaves. Because of the lush and dense foliage, the culms bend outwards. This is why it is called Fountain Bamboo.
This clumping bamboo grows quite quickly and it’s excellent for dense hedges. If you don’t like how much it bends, you can prune some of the branches. It’ll make it stand more upright this way. Fargesia nitida is quite tolerant and hardy. Growing this species in heavy clay soil will not be a problem.
Fargesia rufa ‘Dragon Head Bamboo’
- Type: Clumping
- Height: 6-8 ft (1.5-2.2 m)
- Stem diameter: 0.25 inch (0.6 cm)
- USDA zones: 5-9
- Hardiness: (-10°F / -23°C)
- Light: Part shade, light sun
- Watering: Average
This is another non-invasive bamboo that serves well as a hedge. It is a fast-growing bamboo with beautiful red-colored shoots. Rufa is one of the shortest in the Fargesia genus. However, it will still catch your eye with its beautiful appearance. The bowing canes are green and very thin. It can deal with low temperatures as it is one of the hardiest Fargesias. It can survive in clay soil but you’ll have to take care of draining issues.
Rufa is easily adaptable and doesn’t require much maintenance. If you decide to plant this species in a pot, ensure that you go for a strong material as this bamboo has quite strong roots.
Hibanobambusa tranquillans ‘Shiroshima’
- Type: Running
- Height: 6-16 ft (1.8-5 m)
- Stem diameter: 0.75 in (1.9 cm)
- USDA zones: 6a-9
- Hardiness: (-5°F / -18°C)
- Light: Full sun, part shade
- Watering: Average
This is an elegant bamboo with beautiful culms and evergreen foliage. It is both a full sun and part shade lover. Also suitable for heavy clay soil and can be planted in a container.
This bamboo has very big gorgeous leaves with green stripes on almost white leaves. It is definitely something unique to look at. The green culms can get up to 16 feet (5 m) in height. It also has a broad, spreading habit so you should install bamboo barriers. This species can also be grown indoors.
How to improve clay soil for other species
The better the conditions of your soil, the faster the growth and performance of your bamboo. This is why it is recommended to improve your soil. Plus, you might prefer another bamboo species that cannot deal with heavy soil.
As said earlier, the main issue most bamboo plants have with clay soil is drainage. Wet or boggy soil might cause root rot for several varieties of bamboo. In addition, your bamboos will not grow as healthy and large as they should.
While it might be a bit stressful and time-consuming to improve your clay soil, the whole work will yield results by enhancing the structure of the earth and making it easier to work with. You still need to carry out some annual chores to sustain the soil structure.
One way to improve clay soil is to add organic matter in order to break up its soil particles. This procedure would increase the drainage, bamboo growth, and nutrient retention of the soil. You should wait until you have a dry spell so that it’s easier to dig. Fall, early winter, and sometimes late spring may be good time windows.
4 easy steps to improve clay soils with organic matter
Step 1: Carefully define the growing area for your bamboo plants. If you already have an existing garden bed, dig out the bamboo and set them aside in pots until your soil improvement procedure is complete. You’ll obviously have to start a new garden bed if you don’t have an existing one.
Step 2: Add at least 6 inches (15 cm) of organic matter to the garden bed/ growing area. It could be any kind of organic matter: shredded leaves, compost, grass clippings, rotten manure, mulch. These materials are suitable as long as they’ve not been treated with chemicals.
Step 3: Now, you’ll need to mix the organic matter with the clay soil. This could become an exhausting task since you’re mixing the top 6-12 inches of heavy soil with a lighter material. You can do this by digging the organic matter in and mixing it with a shovel. A way easier method would be using a tiller. You can get this one from Amazon!
Normally, this procedure would leave your garden bed much higher than it previously was. You really don’t have to worry, microorganisms will soon break down the organic matter and your garden bed will become flatter over time.
Step 4: You can decide to begin planting whenever you want. However, you’ll need to continuously add organic matter to maintain the structure of the soil. Add mulch to protect your bamboo from high or low temperatures.
Note: you might want to take a sample of your soil and get it tested for PH issues and nutrients after a season. This would help you to further enhance your soil. If you want to test the pH level yourself, read this.
You can decide to add organic fertilizers to nourish your soil. If you are dealing with pH issues and you intend to decrease the pH of your soil, adding acidic compost would not be a bad idea. Read more about soil and bamboo plant food here.
Overall, these steps would make your clay soil warmer, less prone to compacting, and easier to work with.
The myth of adding sand to improve heavy soil
If you’ve been reading that you can add sand in order to balance heavy soil, you’ve been fooled. We explained how small and flat clay particles are. Sand grains are very large in comparison. Now, to see a real difference, you would need to mix in nearly the same amount of sand particles as you have clay. This would result in a tremendous volume.
So, working in organic matter will be the easier task. Feel the procedures are really stressful? Simply settle for a bamboo variety that’ll do well in clay soil.