Viburnum is a family of plants that has many varieties in it. They are plants that are shrub or hedge like in form, and are generally drought tolerant and durable. Two of the most commonly used Viburnum in our Tampa landscapes are Sweet Viburnum (left in above photo) and Leatherleaf Viburnum (on the right side of the above photo), and those are the two that I will focus on today. While they are very similar in appearance and care, they have vastly different uses in the landscape.
Both of these types of Viburnum are similar in many ways: They have a rounded growth habit, with dense, full foliage that has branches and leaves all the way to the ground. They both have dark green leaves and make very attractive hedges when trimmed. They are drought tolerant once established, have no particular pest problems, are adaptable to many soil and sunlight planting conditions, and are weather hardy.
On closer examination, though, you will see the first difference between the two Viburnums: the leaf. While both leaves are the same size, the Leatherleaf Viburnum's leaf is a darker green, and has a more crinkled or "leathery" appearance, hence it's common name of Leatherleaf. From a distance, though, it is difficult to determine which hedge is which, when mature and trimmed at a height of 4'. You can see the subtle leaf color difference in the side by side photo above, and you might agree with me that it is indeed subtle.
The second, and most important, difference between these two Viburnums is their ultimate growth height, with the Sweet Viburnum growing to 20' tall, and by contrast, the Leatherleaf Viburnum coming in at a mere 6' height. Now you can see why it is important to understand the differences so that you can make an informed decision as to which one to pick for your landscape. Let's look at them individually, given that you will spend many years with either one or both in your home landscape.
The Sweet Viburnum (Viburnum odoratissimum) is fast growing and ideal for privacy hedges, which is one of the reasons that it is so popular. A typical 3 gallon hedge can be installed and within 2-3 years grow to a nice privacy barrier or living fence. Most plants are easy to maintain in the first several years after installation, and Sweet Viburnum is no exception. It is usually in year 4 or 5, though, that you might notice that this plant loves to grow, and to keep it as a hedge at a designated height of 4-6' requires frequent trimming during the growing season, which is almost monthly. This is not the ideal shrub at your home's front entrance if you want something to stay at window-sill height. That is where the Leatherleaf Viburnum comes in:
Leatherleaf Viburnum (Viburnum suspensum) is not as fast growing as the Sweet Viburnum, but it can also be a nice hedge in 2-3 years, albeit a shorter growing one. This one is the ideal choice for a front yard landscaping background plant (also called foundation plant), around an A/C unit or pool screen, or anywhere that you might need a bush or hedge that maxes out in height to 6', and can be maintained at a height of 4'. While it might take a little longer to get there than the Sweet Viburnum, you will only have to trim this hedge about 2-3 times a year. That is important if you are going to spend 20 years + with a plant!
Picking the right plant for the right location is important, as you can see. Both of these Viburnums are extremely forgiving of site conditions and maintenance levels, so either could be used almost interchangeably if it were not for their growth heights. That is a plant characteristic that is too important to overlook, if you want a little more freedom from your yard work. You've heard the old adage "right plant, right place" for success in gardening, right? In this case, size is an important consideration in that adage because if you select the right plant (in growth habit) and right place (in room to grow for desired effect), you will be successful in your landscape gardening, and will be a lot happier with your plants.