Acanthus is also called Berenbroek or oyster plant. Native to southern Europe and the Mediterranean region, this plant is surprisingly more known for its foliage than its leaves.
They have a tall, showy habit that gardeners greatly appreciate. In this article, I will refer to the plant as acanthus, which is similar to its botanical name, acanthus mollis. So, can your plant grow in the shade?
Does the acanthus grow in the shade?
This plant averages 3 to 6 feet (0.9 to 1.8 meters) tall and 3 to 6 feet (0.9 to 1.8 meters) wide. However, this only happens if the plant is in good growing conditions. What is this?
- It should be in rich, well-drained soil with a pH of 6.5 to 7.5 – soggy soil promotes root rot, which can kill the plant. And nutrient-poor soils reduce the rate of food production and therefore plant growth.
- It should be in optimal growth zones between USDA area 6 to 10, or its equivalent. These plants can’t stand harsh winters and can die in such conditions.
- It must be given enough water to support its growth: Ideally, one inch per week should be enough. However, you should always change the watering schedule to ensure the plant is properly watered.
If you meet these conditions, the plant should grow well and bloom from late spring to mid-summer.
The flowers, housed in purple bracts, are tinged with white and rise on 3-foot-long flower stalks. It’s quite a show!
Did you notice that I haven’t mentioned the shade yet? Can your plant grow in the shade?
Acanthus is one of the easiest plants to care for and grows well in shade. In this case, we will divide the shadow into two parts:
1) partial shade
This term also refers to partial sun. Under such positioning, your plant would receive at least four hours of morning sunlight.
It is generally preferable to place the acanthus towards the east of the garden to catch the morning rays, which are softer than those of the afternoon or evening.
If this is not possible, you can place it near an object that can provide shade in the afternoon. Limited access to sunlight allows your acanthus to produce enough food to grow. Moreover, it can still flourish under these conditions.
2) Full Shadow
You might think that full shade means your acanthus doesn’t have access to sunlight. But this is not the case. Instead, it means your plant will receive less than four hours of full sun per day.
Suppose you can place your acanthus in the eastern part of your garden, where it can benefit from 2 hours of morning sun before an obstacle blocks access.
It would be the full shade. The same is true if your acanthus grows under another plant that blocks direct sunlight.
In this case, it would receive dappled light for a few hours. The plant would still produce enough food to grow even under these conditions.
So yes, your acanthus can grow in partial shade or full shade, but acanthus is a light-loving plant. The more light it receives, the more it blooms, but in the shade the leaves grow larger and shinier.
Does the acanthus need sun?
Other than mushrooms, you rarely come across plants that can survive without sunlight. Acanthus will only do well if it has access to sunlight for at least a few hours.
If you want the plant to grow well, place it in full sun. This location must receive at least six hours of unrestricted sunlight between 10 p.m. and 4 p.m.
This access allows Acanthus to photosynthesise, create food to support its growth, and develop its immune system. This allows the plant to flourish well and be less susceptible to diseases and pests. Where can you reach such light?
- In hot climates, place the acanthus towards the east of the garden: make sure the plant has no barriers that limit its access to the morning sun, so that it receives enough light from dawn until around noon. Then install a barrier to the west to keep the plant protected from the bright afternoon sun.
- In cool climates, it is better to place the plant towards the south of the garden: here it has sufficient access to the sun from morning until evening.
Your acanthus will still need some protection when growing in warmer climates. But you still need to make sure it gets enough sunlight to support good food production.
Where does acanthus grow best?
Acanthus is a light-loving and shade-tolerant plant, which means it does well in a variety of circumstances. You can grow it in the following places in your garden:
- Where there is bright, direct light (this is also known as full sun): generally this should be towards the south of the garden,
- Where the plant has access to bright, indirect light (also called partial sun): this would be in the east of the garden. Avoid the west when it receives strong sun,
- Where the plant receives partial shade, which would also be east of the patio, and
- In full shade: This would be to the north of the garden or under a large plant that directs dappled light onto the acanthus.
The best conditions depend on how hot or cold it is in your area. If you live in warmer regions, opt for partial sun, as this is less stressful on the plant.
But if your climate is generally cool, you can grow the plant in full sun. Partial and full shades are only ideal if you don’t want to focus on flowering.
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Advantages and disadvantages of growing an acanthus in the shade
Choosing between growing acanthus in the shade or in the sun is not always easy. The following tips can help you understand what your target is predicting.
Acanthus can handle partial and full shade. And growing up in such conditions has the following advantages:
- The soil does not lose as much moisture to the environment as it does to the sun. So you spend less time watering the plant,
- Most weeds do not grow well in shade. This will eliminate a large percentage of weeds that would compete with acanthus for nutrients. And you spend less on fertilizer because the acanthus can use what is available in the soil.
- You can use shady spots where other plants won’t grow to get the most out of your garden.
Not bad huh ?
The main disadvantage of growing acanthus. full shadow is reduced flowering. Flowering plants need access to sunlight for at least six hours a day to produce enough food to sustain their growth and flowering.
In the absence of sufficient light, the plant maintains leaf production and puts flowering on hold.
So if you want to take advantage of flowering, it is better to move the acanthus partial shade, where you can make more food. Other issues you may face when growing Acanthus in the shade include:
- growth retardation,
- The production of small leaves, and
- The soil can stay wet for a long time.
Keep in mind that these issues are likely to arise when growing Acanthus in the full shadow in colder climates. So if you live in a cold environment, it is best to work in partial shade or partial sun. Better yet, move the plant into full sun.
Acanthus is a very tolerant plant that thrives in almost all types of sun exposure. But keep your USDA zone in mind when making your selection.
The colder your climate, the more sun acanthus needs to thrive. Happy gardening!