Most of the time when we think of a hedge we think of a row of the same plant that is trimmed regularly, usually in front of the house. This type of hedge is pretty useful, because it creates a kind of border around any flowering plants we have there and gives a tidy look near the front door. There are some commonly used plants for these types of hedges, like boxwoods and privets, which fill in to form a solid block of greenery fairly quickly. The best hedges for this purpose stay green year-round, are pest and disease resistant, and have fairly small leaves. Having small leaves is important since regular shearing of the hedge causes many of the leaves to get sliced, and small leaves don’t show the brown edges as much. In addition to focusing on plants that won’t be damaged by freezing weather, I favor using drought tolerant plants for all effects including hedges, in part so that it’s not necessary to install irrigation. So in this category my favorite hedge plant is the California privet, which has somewhat smaller leaves than others in this genus. Despite keeping bright green foliage year-round it can take direct hot summer sun and is very drought tolerant once established.
I’d like to also look at other effects that can be accomplished with hedges, and different ways of achieving them, using a variety of types of plants. One example is a hedge to enhance a plain or boring area behind it, like the wall of a shed or a fence. In this situation we want to have more than just plain greenery, and so using a shrub with colorful flowers or interesting foliage creates visual interest and distracts from what’s behind it. Assuming that we will be regularly shearing this type of hedge also to keep its shape, it’s still important to use plants with small leaves that won’t show damage from trimming. Some good options are escallonia, having clusters of red flowers over a long period of time, abelia, with lots of small pink flowers, or a variegated euonymus, with colorful yellow and green leaves. Another option is to use an assortment of plants to make the hedge, providing variety of leaf color and texture, although to prevent it from looking like a wild jumble there should be repetition of just a few different types.
Another purpose can be accomplished with the tall hedge, basically using plants that grow taller and fill in faster, usually for purposes of privacy or for completely covering an unattractive view that we don’t want to have to look at. In this situation height is important to create a visual wall, but we want the hedge to maintain foliage all the way from top to bottom for a good appearance. It defeats the purpose if after a few years we have a row of bare trunks of plants for the lower half, when what we wanted was a wall of foliage. This is one reason why planting a row of actual trees for screening purposes isn’t always a good idea. Before long the trees not only have a bare trunk at the bottom, but they are rapidly trying to grow much taller and often have to be severely pruned at the top. Maintaining full growth at the bottom of the hedge is also a result of access to sunlight. This is why when shearing hedges we need to have the lower area somewhat larger than the top - slightly like an inverted pyramid. Good choices for this include podocarpus, and once again the dependable California privet.
A barrier hedge can be created using plants with sharp thorns to deter animals, or in some situations, people from crossing over into private property. There are a lot of plants with thorns, but for the purpose of working with plants that can be maintained in a rectangular hedge shape, pyracantha or berberis are good options, although pyracantha is susceptible to fireblight which can cause gaps in the hedge if a plant - even a mature one - dies to the ground. A drawback with a barrier hedge is the difficulty for trimming such a hedge, and the need to wear a thick shirt and heavy gloves. Personally I feel if the objective is to deter, then a hedge with plants having very visible spikes is the way to go, and a good option for this is various types of opuntia cactus (see photo). A hedge made with these will have a fairly informal shape, but by pruning off sections growing in the wrong direction it can be maintained generally in a straight formation. A real advantage is that pieces pruned off can simply be stuck into the ground where they will easily root. A downside is the slow growth, meaning that plants will take several years to grow to size.
Speaking of just sticking something in the ground that will root, there was an interesting kind of hedge I observed while traveling in a tropical region with lots of rainfall and coconut trees everywhere. People would collect a large number of coconuts that fell off the trees and put them in a long row on the ground. They would all root and put up a stem. Each couple of years as the small coconut trees would get larger every other one would be cut out, and eventually there would be a living hedge of coconut trunks.
An important function of a hedge is to provide a backdrop, sort of like a frame around a picture. Informal hedges made with taller junipers or yew trees can take a position behind other plants of interest and need only occasional pruning due to their upright shape. Italian cypresses can do this as well, and they provide a refined look reminiscent of columns in classic architecture, but eventually they can get very tall. Sometimes hedges can be planted so they are seen not straight on but from the side, where the line of the row of plants draws the eye to look further along to a point of interest.
One trick to get a fast effect of attractive flowers in the shape of a hedge is to use vines with large flowers and provide a support structure for them to grow on. There are many flowering vines, and one example is to do this with a climbing rose. The best support can be provided with T-posts, which will be strong for many years and won’t rot like supports made with wood stakes. Combine this with medium gauge aluminum wire to tie the vines to, strung between the posts, which is best because it wont corrode and also wont get hot and damage stems in the blazing summer sun. Don’t forget to consider possible utility lines underground when driving posts, but this structure provides an easy base which will soon be covered by vines for a quick effect and a colorful feature.
The Red Bluff Garden Club is affiliated with the Cascade District Garden Club; California Garden Clubs, Inc; Pacific Region Garden Clubs and Natural Garden Clubs Inc.