How Much Space to Leave Between Each Arrowwood Viburnum Shrub

Arrowwood viburnum (Viburnum dentatum) is a popular landscape shrub prized for its versatility and multi-season interest. With beautiful spring blooms, lush green foliage that turns shades of red and purple in fall, and clusters of blue-black berries that attract birds, it’s easy to see why these adaptable shrubs are a mainstay in many gardens.

When planning an arrowwood viburnum hedge or mass planting one of the most important considerations is proper spacing between each plant. Allowing adequate room between shrubs will ensure your arrowwood viburnums have enough space to reach their mature size and form without overcrowding. Trying to cram too many plants in too small an area can lead to stunted growth encourage disease, and create an unkempt look over time.

Below we’ll explore some key factors to keep in mind when deciding how much space to allow between each arrowwood viburnum in your landscape

Mature Size

Arrowwood viburnum can grow quite large, easily reaching 8-15 feet tall and wide at maturity. Some varieties may even exceed this size in ideal growing conditions.

It’s important to look up the expected mature dimensions of the particular arrowwood variety you are planting. Space plants far enough apart to accommodate their full-grown width and height. Trying to squeeze too many shrubs into a small space will only cause headaches down the road.

As a general guideline, most arrowwood viburnum shrubs should be spaced:

• 8-10 feet apart in a landscape row or hedge
• 10-15 feet between rows

However, verify the mature size of your specific variety before finalizing your planting layout. Some compact arrowwood cultivars may only reach 4-6 feet wide, allowing you to space clumps closer together.

Growth Habit

In addition to mature size, the growth habit of arrowwood viburnum will influence proper plant spacing. Most varieties grow in a rounded, multi-stemmed form with arching branches. However, a few cultivars have a more upright, vase-shaped habit.

Upright selections can often be planted slightly closer together than spreading types before branches intertwine. But even with upright arrowwood shrubs, allow adequate room for air circulation and light penetration between plants to maintain health.

View Obstruction

When using arrowwood viburnum as a privacy hedge or living screen, the desired level of view obstruction will determine plant spacing.

Plant shrubs closer together (6-8 feet apart) to create a thick, opaque screen that completely blocks views and offers maximum privacy. Wider spacing (8-12 feet) will result in a permeable hedge with filtered views through the looser branching structure.

Consider the ultimate function of your arrowwood viburnum hedge when deciding on plant spacing. Closer spacing creates more immediate, but less flexible results.

Growing Conditions

The soil, sunlight, and overall growing conditions of your site will impact how large arrowwood viburnums can grow. Rich soil, ample moisture, and full sun typically equate to larger mature sizes. Plants may grow a bit slower and remain more compact in poorer soils or partial shade.

Evaluate your site carefully and adjust plant spacing accordingly. Shrubs destined for ideal growing conditions should be spaced farther apart than those facing environmental limitations that restrict growth. It’s better to allow extra room than discover plants are crowding each other as they mature.

Aesthetic Appeal

From a purely visual perspective, allow adequate space between arrowwood viburnums to show off each plant to its best effect.

For a tidy, distinguished look space plants far enough apart that branching structure is visible. Filling in all available space can make the viburnums appear congested and indistinct when planted.

Frame views of desirable architectural elements, sculptures or focal points using properly spaced arrowwood viburnums. Generous plant spacing provides negative space that prevents the composition from appearing cluttered.

Air Circulation

Leaving ample room between arrowwood viburnum shrubs allows for free air movement which is crucial for plant health.

Crowding plants together creates a humid environment within the canopy that encourages fungal diseases. Proper spacing allows air to circulate, cutting down on moisture-related problems.

Light Exposure

Closely spaced arrowwood viburnums will end up competing for available sunlight as they grow. Overlapping, intertwined branches block light from reaching within the shrubs. Poor illumination of lower leaf layers can result in defoliation and dieback.

Providing adequate light penetration with smart plant spacing keeps arrowwood viburnum foliage lush and healthy from top to bottom. Take the mature height and spread of your variety into account when designing planting layouts.

Accessibility

Don’t underestimate the importance of leaving enough space between arrowwood viburnums to allow access for planting, pruning, weed control, and overall care. Trying to maintain shrubs that are crowded together can be challenging if not impossible.

Plan plant spacing to accommodate your lawn mower or other equipment. Leaving adequate room makes tasks like mulching and debris clean-up much simpler as well.

Proper plant spacing makes living with your arrowwood viburnum landscape a pleasure rather than a constant battle to control overgrowth. Don’t box yourself in with a spacing scheme that precludes access or maintenance.

Growth Rate

Some arrowwood viburnum cultivars are extremely vigorous and fast growing. Others progress at a more moderate, restrained pace.

Growth rate gives you clues about how soon before plants will grow together and require pruning to control spread. Speedy growers should be allotted more space upfront compared to slower growing varieties.

Pay attention to spacing recommendations for specific arrowwood viburnum cultivars based on known growth characteristics. This will help you avoid plants crowding each other sooner than expected.

Root Competition

Arrowwood viburnum shrubs growing in close proximity will eventually compete for soil moisture, nutrients, and rooting space below ground. This unseen root competition compounds the stresses of tight spacing above ground.

Planting arrowwood viburnums too close together sets up a scenario where roots are struggling for resources in a limited space. Growth will become stunted and plants stressed.

Adequate plant spacing reduces root competition, allowing each shrub to develop a healthy, expansive root system. This anchors the plant and fuels steady, vigorous growth above ground.

Final Spacing Recommendations

Taking all these factors into account, here are some final guidelines for optimum arrowwood viburnum spacing in various landscape situations:

• As a hedge or screen – Space plants 6-12 feet apart depending on desired density and view obstruction
• In a shrub border – Allow 8-12 feet between plants to showcase form
• Near pathways or lawn edges – Leave at least 5-6 feet between shrubs and hardscape
• In island beds – Space plants 8-10 feet apart for air circulation
• Along property lines – Use 10-12 foot spacing to avoid encroaching on neighbors

These spacing recommendations serve as a helpful starting point. But always tailor plant spacing to the specifics of your landscape site, arrowwood variety, and design goals.

When planning your arrowwood viburnum layout, allow enough room between shrubs to achieve your ideal aesthetic effect and facilitate proper care. Avoid the temptation to cram too many plants together in limited space. With smart plant spacing, your arrowwood viburnums will thrive and enhance your landscape for years to come.