High maintenance may be needed to keep them looking that way. But, in many cases, it’s worth it.
Finely manicured, pristine and regal, hedges can add a sense of dignity and flair to a golf course landscape. Unfortunately, in most cases, hedges and high maintenance go hand in hand. In order to create a formal hedge, lots of time and effort must be invested in pruning, shearing, shaping, fertilizing, watering and controlling pests.
On the other hand, there are times when high maintenance is acceptable, usually on high-focus areas such as the first tee or near the clubhouse, especially if combined with other ornamental plants. Even on low-budget courses, exceptions can be made to a low-maintenance approach. After all, not too many golfers want to play a course in which the only vertical elements are the flagsticks and ball washers.
In addition, there are alternatives – naturally shaped and lower-maintenance plant arrangements where a hedge brings amenity without adding lots of maintenance. These types of plantings provide the best of both worlds.
Location, location, location
Hedges aren’t suited for every location on the course. They must be well-sited, taking into account their function, purpose, sun/shade requirements, height, width, density, bloom sequence, fall color and other selection criteria.
Hedges are ideal for areas where a backdrop or taller piece of a layered golfscape is lacking. Low- and medium-height plants may already be located in these areas, and 6- to 8-foot-tall plants are required to finish the sequence or provide scale to shorter specimens that otherwise may be understated.
From a functional standpoint, hedges should be placed where air circulation is abundant. Tightly clipped plants are dense, decreasing air circulation and flow, creating a humid microclimate where leaves stay moister than nearby plants, increasing the potential for foliar disease on the hedge itself and possibly the others nearby. In some situations, the turf can also be affected.
Another functional feature of hedges is their potential for separation or screening of undesirable views. It’s hard to enjoy the golfing experience while gaping at a rundown convenience store or municipal gravel processing facility.
Be careful with locations … planting hedges under picture windows can lead to increased maintenance when views of the course are important. Placement in areas of frequent play can also be problematic. Ground covers and hedges tend to be good ball traps, areas where errant balls can be gobbled up, causing poor players with bad etiquette to spend time pushing aside foliage in search of a $1 item.
Shrub maintenance isn’t usually all that difficult, except when there are 20 in a perfectly aligned row and they all need to look exactly the same. When dealing with a closely spaced grouping, it’s important to remember that the goal is to keep the entire surface full of foliage. This tends to be more difficult with hedges than single specimen shrubs because they receive shading from nearby plants as well their own stems. After years of pruning, many hedges have exposed dead inner wood/stems, as well as some that are alive but produce no leaves. Overall, the most important goal is to keep the top of the hedge narrower than the bottom in an effort to keep the entire plant green and producing healthy leaves.
Pruning makes a hedge a hedge, and there are three basic approaches:
- True hedge style – shaping to a predetermined height and width. Also called shearing, hedge pruning is done every year, usually between two and six times. Though this produces an attractive formal appearance, it can also leave the hedge with areas of dead growth or no growth at all. Instead, a 2- to 3-inch layer of knotty growth results where the hedge shears have repeatedly removed stems, creating an edge of very short, compact stems.
In order to prevent this from occurring, the height and depth of cut must be varied each time the hedge is sheared. Doing so will allow light and air to penetrate to the center of the plants, producing more viable and vigorous growth. Considering the overall goal of keeping the top narrower than the bottom, it is often helpful, at least with the first shearing, to set up a template of stakes and string to force the top to be sheared narrower. For example, the stakes may be 28 to 30 inches apart at the top and 38 to 40 inches apart at the bottom.
- Natural style – thinning then shaping. A more natural approach to hedge pruning involves removing one-third of the oldest canes/stems at the ground level each year. This method produces two important benefits: it lowers the height and width of the hedge as these stems tend to be the largest, and it encourages new, vigorous stems to grow. The newer stems tend to be more robust and flower more freely because of the age of the wood. After the older stems are removed, hand pruners can be used to remove aberrant growth on the sides and top.
- Really natural style – utilizing right plant, right place and wider spacing to allow for full development of plants. In this management approach, pruning is not practiced unless stems die or become diseased. When this method is chosen, one must be satisfied with the eventual size of the hedge, no matter how large it grows to be. Most horticulturists prefer this method.
As a part of any of the three approaches, renewal pruning can be conducted to breathe new life into a hedge. This method is as simple as it gets; the stems are simply cut off at the ground level using a chain saw or hand pruning saw. In some cases, the person pruning the hedge tries to “outthink” the job and leaves a couple inches of woody stem in the mistaken notion that leaving something is better than totally denuding the plants, but doing so creates an arrangement in which older wood, which is attractive for borer infestation and heartwood decay, crown rot or armillaria root rot infections, remains in the plant. Renewal pruning works well for deciduous cane growing shrubs and hedges such as forsythia, weigela, privet, dogwood, euonymous, viburnum, spirea and lilac, but not for evergreens, as they lack adventitious or epicormic buds at the ground level.
- Insects and diseases – Though it’s difficult to paint the pest control picture with a broad brush, controlling insects and diseases is usually more difficult when maintaining hedges than single specimen shrubs for several reasons. First, because of the difficulties experienced in pruning to an unnatural shape and size most hedges are under a greater amount of stress; plants under stress are more attractive to insects than healthy plants, and are less likely to outgrow a foliar disease outbreak. Secondly, from a disease standpoint, denser foliage tends to allow less air flow through the canopy and dry off slower after receiving rainfall or overspray from an irrigation event than single plants, which keeps the humidity higher and creates better growing conditions for mycelial growth. Third, as mentioned earlier, improperly pruned plants are more likely to become borer infested than ones that are well maintained. When the task at hand is to prune a long line of shrubs attention to detail often wanes, making it likely that the person pruning the hedge may lose focus at times.
- Weed control – The third common pest of hedges, weeds, is likely to be no greater of a problem than it is for single shrubs; in fact, in some cases it could be a bit less. Due to the dense canopy sunlight penetration is commonly reduced, creating less-suitable conditions for the germination of problem trees, such as Siberian elm and mulberry as well as annual grasses including crabgrass, foxtail and goosegrass, when compared to solitary shrubs or ones grown in well-spaced plantings of threes and fives. The traditional control method of mulching to suppress weed and grass invasion, retain moisture and keep roots cool goes a long way towards achieving adequate weed control in hedges.