Outdoor bamboo is one of my favorite plants to have in the garden because it acts as an elegant screen, and they are incredibly hardy once it is established. However, a very common problem that I have experienced myself is that the leaves can turn yellow. In this article I share with you the steps I took to identify why my bamboo leaves were turning yellow and the steps I took to save it…
From my experience working as a commercial plant supplier, the most common reason for outdoor bamboo turning yellow is usually because of too much wind. Bamboo is native to humid climates and grows in moist yet well-draining soil. It does not tolerate strong, cold, dry winter winds that scorch the leaves yellow. Excessive dry or damp soil also causes bamboo leaves to turn yellow.
Here are all the most common reasons I see for bamboo leaves turning yellow:
- Too much wind saps moisture from the bamboo’s leaves, scorching them yellow. (Bamboos need sheltering from cold, dry winds in Winter).
- Saturated soil from overwatering or boggy ground prevents the bamboo roots from drawing up moisture and nutrients, resulting in yellow leaves. (Bamboo grows best in moist yet well-draining soil composed of organic matter and good compost).
- Excessively dry soil and high temperatures prevent the roots from drawing up enough moisture, causing the leaves to turn yellow. (Bamboo can tolerate some drought but prefers consistently moist soil).
- Alkaline soils prevent the bamboo from uptaking nutrients. (Bamboo grows best in slightly acidic soil and can tolerate a pH range of 4.5 to 7.5)
- Too much sun can scorch some specialized cultivars of bamboo plants’ leaves yellow. (Most bamboo varieties can tolerate direct sunlight; however, some cultivars are more sensitive to the sun, which can turn the leaves yellow).
Keep reading for the steps I took to save my bamboo…
(If your indoor lucky bamboo is turning yellow, read this article instead for how to save it).
Excess Winter Winds Turns Bamboo Leaves Yellow
Bamboo is native to tropical regions and prefers to grow in warmer, humid conditions. Strong dry winds combined with cold temperatures in Winter can sap moisture from the bamboo leaves, which turns the leaves yellow and can cause them to fall off.
I have found that the specific combination of cold temperatures and wind results in yellowing leaves, as I observed my leaves do not turn yellow in the Summer, no matter how strong the wind is.
I love to plant bamboo in people’s gardens as it is such an effective visual screen in gardens and can tolerate some wind and freezing temperatures, although, from my research, I discovered the leaves often turn yellow and fall off if there is a cold snap with an air temperature of 26.6°F (-3°C).
The air in Winter in cooler climates is naturally much lower in humidity, particularly if there are freezing temperatures, which is in direct contrast to the preferred humid conditions to which bamboo is adapted in common bamboo’s tropical humid natural habitat; therefore, the risk of leaves turning yellow or brown and dropping in Winter is substantially increased.
With relentless cold Winter winds that are low humidity in exposed areas, bamboo leaves inevitably turn yellow and brown to some extent, even if the temperature remains above freezing.
How to Save it…
Once the bamboo’s leaves have been scorched yellow by cold winds and low humidity, they do not turn green again.
The good news is that the rhizomes that are underneath the ground are well insulated from freezing temperatures, so the bamboo is likely to revive when the conditions become more favorable in Spring, with new green leaves replacing any yellow leaves that have likely fallen off over Winter, so do not worry!
In order to prevent the bamboo’s leaves from turning yellow in Winter, move the bamboo (if planted in a pot) to a more sheltered location to prevent wind from scorching the leaves.
If the bamboo is planted in the ground, I recommend finding a way to provide shelter, perhaps with an evergreen shrub or using horticultural fleece to deflect the wind. The bamboo should grow new green leaves in spring.
Can Yellow Bamboo Leaves Turn Green Again?
If outdoor bamboo leaves turn yellow, they do not turn green again. However, if you address the problem that caused the bamboo’s leaves to turn yellow, the yellow leaves often drop off, and new green leaves grow again in the Spring and Summer.
Excessively Damp Soil Causes Yellow Bamboo Leaves
Bamboo leaves turn yellow if the soil is too boggy due to overwatering or slow draining soils. Bamboo needs to grow in soil that is moist yet well-draining. If the soil is saturated, the bamboo leaves turn yellow and eventually fall off.
I always think it is important to understand how plants grow in their native environment to understand how we can save them…
Bamboo grows naturally in soils with a very high organic content (decomposed leaf litter) in its native environment, which can hold moisture yet still be very porous and aerated so that excess water can drain away effectively from around the roots.
Too much water can exclude oxygen from the soil. If there is not enough oxygen in the soil the bamboo’s roots cannot respire and therefore cannot draw up the moisture and nutrients that the bamboo needs, which results in the leaves turning yellow.
If the soil stays saturated for too long, the roots start to rot, a common cause of dying bamboo.
Heavy clay soils are typically not porous enough to allow for good drainage, promoting the conditions for the bamboo leaves to turn yellow.
However, damp soil may also be caused by overwatering, low-lying areas that naturally accumulate water, natural springs, or because the bamboo is planted in a pot without drainage holes in the base.
How to Save it…
Unfortunately, the only way I found to save a bamboo with yellow leaves due to saturated soil is to transplant the bamboo to well-draining, porous soil, which replicates the soil moisture conditions of the bamboo’s native environment or to a pot or raised bed.
What I would do is prepare a new planting site for the bamboo by digging in the soil and amending the planting area with compost or leaf mold, which is able to hold moisture yet allows for good drainage.
Gently lift the bamboo out of the soil (ideally using a garden fork to avoid damaging the roots) and transplant it into the new location.
Useful tip: If your garden soil is particularly heavy clay, then I would recommend transplanting the bamboo to a pot or raised bed, as it is much easier to create the right well draining, yet moisture retentive soil conditions that the bamboo requires (by filling the pot with compost).
If your bamboo is planted in a pot ensure the pot has a drainage hole in the base and check to see whether the drainage hole is clear.
What I do is I elevate my pot off the ground with ‘feet’ (commonly available from garden centers) or bricks to further ensure good drainage.
Whether or not the bamboo recovers depends on how long it has been in damp soil. The yellow leaves are likely to fall off before new green leaves emerge in Spring and Summer.
From experience, bamboo is incredibly hardy and is better at making surprising recoveries compared to most garden plants!
Your Soil is too Dry
Bamboo leaves turn yellow if the soil is too dry. Bamboo is native to tropical environments and grows in consistently moist soil. If the soil around the bamboo’s roots dries out completely, the leaves start to turn yellow and fall off.
From my own experience, bamboo leaves turning yellow due to drought usually happens when the bamboo is planted in a pot. Pots can dry out much quicker in the blazing Summer sunshine and, therefore, need frequent watering to cope with hot and dry conditions.
Most of the time, when I see yellowing leaves, it is because the bamboo is in a pot that is too small, as smaller pots have less capacity for soil and hold less moisture.
I have also seen bamboo planted in dark-colored pots or pots or even metal containers, which conduct far more heat and can dry out the soil too quickly for the bamboo to tolerate.
Bamboo plants that are planted in garden soil can also turn yellow if the soil is naturally sandy or on a slope and, therefore, dries too quickly for the bamboo to draw up enough moisture to support the leaves, causing them to turn yellow.
If the bamboo leaves have turned yellow, they do not turn green again, and they are likely to fall off.
How to Save it…
The best way to save bamboo with yellow leaves due to drought is to recreate the bamboo’s natural conditions by ensuring the soil stays consistently moist.
To do this bamboo in pots, it may be necessary to repot your bamboo to a larger pot. A larger pot has more soil and, therefore, can retain moisture for much longer.
Top tip: My favorite pots are Ceramic or unglazed clay pots as they do not heat up in the sun to the same extent as other containers and they are also porous which makes it easier to maintain the optimal balance of moisture (moist soil, yet well draining) for the bamboo to thrive.
It is important to note that bamboo is likely to need watering in Summer. I personally soak my bamboo every week during Summer, particularly if there is low rainfall.
Water thoroughly so that excess water trickles from the base of the pot to ensure the soil is evenly moist and the moisture has reached the roots, where it is required.
If the bamboo is planted in garden soil and the soil is drying out too fast, water the soil generously and apply a 2-inch layer of mulch (compost, leaf mold, or well-rotted manure are all great mulches) around the base of the bamboo to help the soil retain the moisture. I can assure you that the mulch makes a huge difference.
If you apply compost mulch to the base of the bamboo every year, then this improves the soil structure and ability to retain moisture to mitigate the effects of drought.
By creating more favorable conditions, any remaining green leaves are likely to stay green, however, any leaves that have turned yellow are likely to fall off but I always see new leaves grow in the Spring and Summer.
Bamboos are hardy enough that their leaves can turn yellow and become completely defoliated due to dry weather and yet recover in the Spring.
Alkaline Soils Causes Yellowing Leaves
Bamboo grows naturally in soils that are between pH 4.5 and 7.5, which means it can grow in acidic soils (which are most common) soils that are neutral and tolerate some alkalinity.
However, if the soil is higher than pH 7.5 (pH 7 is neutral, and any value higher than 7 is alkaline), then this is at odds with the bamboo’s preferred environment, and the roots struggle to draw up some of the nutrients it requires for the leaves to stay green and results in yellow leaves with poor growth.
It should be noted that this is a far less common cause of yellowing bamboo leaves as garden soil tends to be slightly acidic or neutral in general, but it can be a problem in certain locations. An unusual reason for alkaline soil that I think you should be aware of I came across was when one of my gardening clients had amended the border around their bamboo with lots of wood ash, which is highly alkaline.
How to Save it…
If you have plants such as roses, camellias, rhododendrons, etc. in your garden (which all thrive in acidic soil) or perhaps in gardens around the neighborhood, then it is unlikely your garden soil is too alkaline for bamboo and the yellow leaves are more likely as a result of wind, drought or saturated soil.
You can test garden soil with a soil meter to measure the pH of the soil if you suspect that alkalinity is the problem.
The photo shows the soil gauge that I used, which immediately identified the highly alkaline soil, which was due to the wood ash that was amended to the soil.
How I solved this by adding sulfur to the soil to increase the acidity (available from garden centers or online), but consistently changing the pH of your soil is a difficult and potentially expensive task, so I recommend planting (or transplanting) bamboo in pots as you can add normal potting soil which has the right characteristics for your bamboo to thrive.
If the bamboo has sustained significant leaf yellowing and poor growth as a result of alkaline soil, then it may not recover.
Too Much Sun can Scorch Leaves to Yellow and Brown
Common bamboo grows in a wide variety of habitats in its native range, from shady areas to open areas with full sun, therefore most bamboo is resilient to strong sunlight, so this is rarely the cause of yellow leaves.
However, I have encountered some ornamental bamboo cultivars that are more sensitive to full sun and can scorch yellow and brown with too much direct sunlight.
This can also be because bamboo has been cultivated in specific conditions in a commercial greenhouse before being sold in the garden center.
If the bamboo has been grown in partial shade or bright light and then moved to an area of direct sunlight when you plant it in your garden, then the sudden contrast of conditions, without time to acclimatize can cause the leaves to scorch yellow.
How to Save it…
Whilst most bamboos tolerate full sun, there are some varieties that are cultivated for ornamental use, which are much more sensitive, so if you have any labels or directions from the garden center, try to find out which variety you have and plant accordingly.
Once the bamboo leaves have been scorched yellow by too much sun, they do not turn green again.
The only way to save it is to transplant the bamboo to a new location with partial shade. Morning sun, followed by afternoon shade, is most often ideal for bamboo plants.
You can also plant a shrub near the bamboo to create filtered light.
The scorched leaves may eventually drop off, and new leaves should grow in the Spring or Summer. Bamboos are often very hardy plants and do tend to revive even if a lot of the leaves have turned yellow or dropped off.
Key Takeaways:
- Bamboo leaves turn yellow because of wind scorch, excessively dry or damp soils, too much sunlight, and alkaline soils. High winds combined with cold temperatures in Winter saps moisture from the leaves and is the most common reason bamboo leaves turn yellow.
- Yellow bamboo leaves do not turn green again. Typically, the yellow leaves drop off and regrow in the Spring and Summer if the growing conditions are more favorable, with less wind, warmer temperatures, and moist yet well-draining soil.
- To fix a bamboo with yellow leaves, recreate the conditions of its natural environment by protecting it from drying winds in Winter, ensure the soil stays moist during drought, and transplant bamboo into pots if the soil is too boggy. The yellow leaves usually drop off, and new green leaves emerge in the Spring.