How to Care for Boxwood — The Ultimate Guide

Sharing is caring!

Undoubtedly, one of the most popular ornamental plant genera, Boxwoods are very hardy, versatile, evergreen shrubs. The first reported Boxwood garden plantation in North America took place in 1653! 

The evergreen shrub is truly, “Man’s Oldest Garden Ornament.”

The Boxwood genus comprises about 97 species and hundreds of cultivars, the most familiar one is Buxus sempervirens, or its ‘Suffruticosa’ English Cultivar. 

 

Boxwood Care

Boxwoods prefer well-draining sandy loam. They need 6 hours of direct sun a day for optimum foliage density. Boxes need moderate amounts of water but be careful not to overwater. Give a hearty drink of water every time the top few inches of soil dry up. Ideal temperatures are 60-80°F (15-26°C).

 

Soil

Boxwood shrubs will thrive in well-drained, rich organic soil. Boxwoods roots grow shallow so give them evenly moist soil but ensure adequate drainage. They are susceptible to root rot in waterlogged soils. They can tolerate soil pH levels from 6.5 to 7.5, while a value of 7.1 is preferred.

When it comes to the soil requirements for your Buxus plants, they are pretty resilient and can tolerate a wide range of soil types from chalk, sand, loam to heavy clay. 

That being said, it must also be mentioned that the ideal soil type is sandy loam. This type of soil provides the best drainage, aeration, and nutrition Boxwoods need to thrive. 

Regardless of whether the soil is predominantly sandy or clayey, good drainage is an absolute must in any case. These shrubs will not fare well in waterlogged soils and will suffer from root rot. 

As far as the soil pH levels are concerned, these evergreen shrubs can tolerate anything between the range of 6.5 (slightly acidic) to 7.5 (slightly alkaline). However, the ideal pH is 7 (neutral) to 7.2 (slightly alkaline).

Before you plant Boxwoods in your garden, it is a good idea to do a pH test of the site. 

If the soil turns out to be too acidic or alkaline, you will save yourself a lot of inconvenience by adjusting the pH up and down in the soil before you plant your Boxes.

If you think your garden soil is too heavy or too infertile to support healthy Boxwood growth, you might as well prepare a special soil mix for your garden ornaments. 

For ground-grown shrubs, dig a hole that is 1-2 feet more than the rootball of your Boxwood, and fill the space with your custom-made Boxwood soil mix. 

This soil mix recipe can also be used to grow Boxwoods in pots. Use the following ingredients in equal parts. 

• composted pine bark 
• peat moss
• sand
• perlite 
• compost

For every 5 gallons of soil mix created, add 3-4 ounces of powdered limestone to adjust the pH to perfect levels. 

 

Light

Different Boxwood varieties have different light requirements. As a rule of thumb, boxwoods grow in full sun to light shade. They prefer at least 6 hours of direct sun a day for optimum foliage density. Protect Buxus plants from harsh midday or afternoon sun if you live in a hotter climate. 

The quality of light a Boxwood shrub receives every day plays a massive role in the color and density of the foliage. Put briefly, the right light levels are essential for good-looking Boxwood shrubs.

Being outdoor shrubs, Boxwoods generally enjoy full sun to partial shade. There is no better sight than spherical Boxwood bushes soaking up the sun on a summer afternoon.

Being versatile plants, these hardy bushed can also be grown under tree canopies or beside walls where they don’t get direct sunlight for a major part of the day.  

Boxes will do well in bright indirect light if planted under trees or grown on your porch or patio. 

The evergreen shrubs will thrive in direct sunlight, but they will need to be protected from harsh afternoon sunlight if you live in a region with a hot and dry climate.

Plant boxwoods in light shade or filtered sunlight if you live in an arid climate. 

Boxwoods can be grown indoors successfully if provided with sufficient light. Although they can tolerate partial shade, they will grow best if placed somewhere that gets direct sun for 4-6 hours a day.

In front of a South or East facing window are good locations for growing Boxwood indoors. In summers, place the plant beside the window, out of direct sunlight to avoid sunburn.

 

Water

Newly planted Boxwood plants need to be watered frequently. Watering can be decreased as the plants grow and get established in the ground. Boxes need moderate amounts of water but be careful not to overwater. Give a hearty drink of water every time the top few inches of soil dry up. 

A wise watering practice is essential for Boxwood care. As a lot of Boxwood diseases originate from irregular and improper watering, your plants are sure to be healthy if the watering is right.

When growing Boxwoods in the ground as shrubs, regular watering is required for the first two years to help the plants grow well and get established in the ground. 

Once the shrubs are old enough, they get well-established in the ground and will not need to be watered very often. 

Mature shrubs are pretty drought-resistant. But keep in mind, their roots do not grow very deep and lack the ability to find water deep in the ground.

You will still need to water ground-grown shrubs in hot and dry spells to prevent the risk of your Boxwood shrub drying out. 

For potted Boxwoods, you will need to give them a heavy drink every time the top two inches of the soil dry out. Water deeply so that it flows out of the drainage hole. 

Deep watering ensures all parts of the rootball get wet and all roots of the plant are able to absorb moisture. 

When Boxwoods suffer a lack of water, the dulling and discoloration of the foliage is a major symptom. Check the soil moisture if you spot dull foliage or yellow spots on leaves. 

Whether you’re growing Boxwoods in the ground or in pots, always water the plants at the base and not on their foliage. Watering onto the foliage can lead to a range of foliar diseases for your Boxwoods. 

Mulching the soil around Buxus plants is a recommended practice from expert Boxwood growers. Mulching not only retains soil moisture and keeps the shrubs supplied with adequate water consistently, but it also has a range of other benefits. 

Mulching the nearby soil also prevents the growth of weeds, maintains soil temperature, and reduces the risk of your shrubs catching Boxwood blight. 

 

Temperature

Boxwoods are hardy to USDA zones 4-10. They are hardy and versatile plants that can tolerate pretty low to high temperatures. They stay green even in the winter and can tolerate freezing temperatures as low as -10°F(-23°C). The ideal temperature range for this plant is 60-80°F (15-26°C).

The astoundingly wide temperature range Boxwood plants can tolerate is one of its most remarkable qualities. 

From freezing temperatures as low -10°F(-23°C) to as high as 95° (35°C), your Boxwood plant will endure these extreme temperatures like a breeze.

If you live anywhere between USDA zones 4-10, you can grow Boxwood shrubs outdoors year-round without a worry. It is, however, a good practice to do your best to protect your plants from extreme cold or hot weather. 

Prolonged exposure to cold and dry winds, frost, and intense sunlight can cause Boxwood foliage to turn brown and crispy, or bronzing of the foliage.

If your Boxwood is growing in a pot, it’s better to relocate the plant to a sheltered location in both extreme cold and hot weather. 

In winter, you can protect your Boxwood bushes from the damaging effects of winds and frost by protecting them with burlap wraps, decorative protection, or installing windbreaks. 

Mulching the soil will keep the soil temperature maintained both in the summers and winters. A mulch layer insulates the roots from freezing cold temperatures in the cold. 

In the same way, it prevents excessive moisture escape by keeping the soil cool and comfortable for the plants in extreme heat.

 

Humidity

Boxwood plants do not have any special humidity requirements and will do well regardless of atmospheric humidity. They can tolerate humidity levels as low as 10% to as high as 90%. However, high humidity conditions increase the risk of foliar fungal diseases and Boxwood Blight. 

The atmospheric humidity levels are not something to worry about for Boxwood owners. These plants do not need specific humidity levels to thrive. 

Whether growing Boxwood indoors or outdoors, they will do well in the natural humidity that is present. 

Just take care not to place the plant too close to sources of cool or warm air which will quickly steal the plant of all its moisture. 

Care must be taken in high humidity weather to keep the plant safe from fungal infections. 

If water sits for too long on the foliage in high humidity, fungi can take advantage of warm and dark conditions to grow onto the foliage and infect the plant.  

Hence, keep your Boxwoods well-ventilated and water them only at the base to avoid the risk of infection. 

 

Fertilizer

Feed your Boxwood shrubs with a suitable dose of all-purpose fertilizer in Spring and throughout the growing season to promote healthy and fast foliage growth. The Boxwood root system is quite shallow and is prone to over-fertilization, so make sure you don’t add excess fertilizer. 

Boxwood shrubs like growing in rich soil, abundant in all the nutrients these plants need for growing shiny and dense foliage. 

Not all soils are the same, and your garden soil may or may not need regular fertilization to grow vigorous Boxwood shrubs. While your garden shrubs will enjoy fertile soil, you don’t want to add excess nutrients to already fertile soil. 

To take the uncertainty out, and to ensure you give your Boxwoods the perfect permanent home, test for nitrogen in the soil and other important nutrients. 

If you find the soil nutrients below the optimum levels, you must fertilize the soil regularly. The best fertilizers for Boxwoods have a significantly higher nitrogenous content that supports vigorous foliage growth. 

If your watering practice is consistent but you still notice dull or yellowing foliage, this must be a sign from your plant that it needs to be fed.

Boxes do not usually drop a lot of leaves, but if you notice considerable leaf drop this is another sign of nutrient-deficient soil. 

Regardless of whether your plant displays these signs or not, you can still fertilize it in Spring and early summer for vigorous foliage or in late fall to encourage healthy roots. 

As mentioned earlier, Boxwoods have a shallow root system and are susceptible to root burn if excess fertilizer is added. 

The best practice to prevent this is to mulch the soil around the shrubs, water well before fertilization, and always use mild or diluted fertilizer doses. 

 

Growth

Boxwoods are well-known for their very slow growth rate, typically 6 or fewer inches of new growth per year. They are evergreen, broadleaf shrubs with ovate, glossy leaves. Buxus sempervirens can grow 1-9 m in height. The ‘Suffruticosa’ cultivar only grows 2-3 ft in height and up to 4 ft in width.

Boxwood owners are often frustrated with the plant’s sluggish growth rate. So, if you’re going to grow this plant in your garden, you must be really patient with it. 

You are not going to get perfectly round-shaped Boxwood shrubs overnight. Young Boxwood plants can take years to grow big enough to be pruned to a spherical shape.

While you can speed up the growth rate by fertilizing the plants and growing them in the ground with ample water, you can get no more than 12 inches of growth per year. 

That said, the slow-growing behavior of these evergreen shrubs is also what makes them so suitable to be grown as ornamental garden plants. 

Once pruned to shape, you will not have to prune them back again and again to maintain their look. They will hardly require pruning once or twice a year. 

If left to grow unattended, Buxus Sempervirens will grow into a dense bush or a small tree as tall as 9 m. 

The leaves are firm and ovate, arranged in pairs, facing each other along the stems. Leaves can grow 1.5-3 cm in length and 0.5-1.3 cm in width. 

Boxes are rarely seen flowering, but when they do, the blooms are very aromatic but are hard to identify as being inconspicuous. The scent is not very pleasant in most Box varieties. 

Blooms result in small, three-lobed capsules that are green in color and blend in with the foliage. The fruit turns brown when ripe. 

 

Potting

Boxwoods are excellent plants for growing containers given that the container has adequate drainage, and is wide enough to support the plant’s shallow, wide-reaching roots. The pot should ideally be as wide in diameter as your Boxwood’s height. Terra cotta pots are recommended for their benefits.

Slow growth and the need for moderate soil nutrition, the perfect traits to grow a plant in containers. 

While Boxwoods are typically grown as decorative shrubs in the ground, they make excellent pot plants and look very beautiful in them. 

Terra cotta pots are good for plants because of the porous texture of the clay, which allows healthy air exchange between the soil and the atmosphere. 

However, you can grow your Boxwood plant in any decorative pot made of any material as long as it is well-draining and is wide enough to support the wide root system. 

Add a layer of small rocks or pot break pieces to line the bottom of the pot to ensure quick drainage and prevent the drainage hole from getting clogged. 

As your Boxwood grows, you will need to repot the plant after every 2-3 years. 

 

Pruning

Pruning your Boxwoods the right way is an essential part of Boxwood care. Pruning is best done in late Spring or Summer and should not be done in fall and winter. Thinning the outer foliage is essential to allow air and light to reach the core of the plant. Dead leaves and twigs must be removed too.

Although Boxwoods are very slow growers, pruning is an essential part of Boxwood care, especially when you want the shrubs to be in a specific shape.

Pruning these plants to shape, and then the usual maintenance pruning doesn’t seem as straightforward as it looks on the surface. 

There are many factors that must be considered, ranging from the time of pruning, the extent of pruning to using the right type of shears. 

The hardy shrubs will respond best to pruning in late Spring and Summer when they are growing the fastest. 

Pruning in fall and winter should be avoided because this exposes the core of the plant to cold winds and frost, and the new growth will be too delicate to withstand the low temperatures. 

Hard pruning Boxwood shrubs is not recommended as it promotes rapid, unbalanced growth. Always prune the plants lightly from all areas to grow them to shape. 

Thinning is an important pruning technique for Boxwood shrubs. The dense foliage looks very pretty on the outside, but it prevents the much-needed air and light from reaching the inside of the plant. 

Open up the insides of the plant by removing one or two older branches every subsequent year. This might damage the aesthetics, so better to remove branches from a side that is often hidden from sight. 

Remove any dead, damaged, or diseased foliage as soon as you see it to promote new, healthier growth. 

 

Boxwood Propagation

The best time to take Boxwood cuttings is late Summer to Fall. Take hardened or semi-hardened stems from a healthy part of the plant. Cuttings should be 4-6 inches long. Plant them in a sterile sandy mix and keep the soil moist. Cover the pot with a plastic bag. Cuttings will root in 3 months.

Propagation by stems is by far the most straightforward method for Boxwood propagation. These shrubs do not fruit very frequently so seed propagation is not reliable. 

Take 4-6-inch hardened stems by making a slanting cut. The slant cut ensures the maximum surface area for the stems to absorb moisture and to root quickly. 

Use a sharp and sterilized pruner to take the cuttings. You can use a rooting hormone to treat the cuttings to boost chances of success. 

Cuttings typically root within 3 months. However, they should be left in their container over the winter. Transplant them to their new home in the Spring. 

 

Common Problems with Boxwoods

Boxwoods are very hardy plants and are not easy to kill. The foliage is toxic if ingested and is deer-resistant for the same reason. Here are some common problems you may face while growing Boxwoods.

Boxwood Blight

Boxwood blight is a fungal disease caused by a pathogen called Calonectria pseudonaviculata. The symptoms are leaf spots, cankering, leaf drop, and eventual death of Boxwood plants.

Mulching the soil can reduce the chances of blight infection. To get rid of Blight in the soil, remove the diseased foliage and ensure the soil gets a lot of sun. 

Blight can be treated with selected anti-fungal formulas. This disease does not affect the roots and the plant can recover if infected foliage is removed. 

Pests

Boxwoods are susceptible to infestations from Box leaf miners, scale, caterpillars, lesion nematodes, and mites. These pests can easily be treated with frequent mild sprays of organic neem oil or other insecticides.

 

Conclusion

Boxwood, Man’s Oldest Garden Ornament, is a treat to grow, whether you’re growing it as a shrub, potted plant, or as a Bonsai tree. 

Their magnificent foliage and the ability to prune them to any shape you like make it one of the best hedge plants. 

Follow recommended practices such as mulching the soil and proper pruning, and you will have marvelous Boxes adding to the color and regality of your garden. 

 

 Frequently Asked Questions about Boxwoods

 

What are alternatives to Boxwood?

There are many boxwood lookalikes that can be planted instead of actual Boxwoods. Myrsine Africana, Ilex crenata, and shrub Honeysuckle are some examples. 

 

How hard can Boxwoods be pruned?

It is not advisable to prune back Boxwoods hard. Pruning back 2-3 feet in height at a time is safe.