I often get questions on how to prune crape myrtles. I’m asked “how do I keep the branches from hanging so low if I’m not supposed to top them?” So the answer is in the question. If lower branches are the problem, why would you prune the upright limbs?

In August, when crape myrtles are hanging full of blooms and seeds, especially after a rain, the limbs can drape low, especially on the fauirei crosses. To prune, remove the low hanging branches, either at the main trunk or at a branch crotch. Do not chop them off haphazardly, leaving unsightly nubs. Do this every year until the canopy is up and over where you want it to be.

This method is simple, but can be more complicated when a tree has previously been topped, causing many, small branches to form at the pruning site. Using hand clippers, remove most of the cluster, leaving ones that grow more parallel to the ground (taking out the weepy ones and very upright ones). This is a slow process that takes several years to correct.

In between serious prunings, it is fine to take hand clippers and remove any low-hanging flower/seed heads. Removing the extra weight from the branch will cause it to stand more parallel to the ground, rather than weep.

Winter is a great time for planning or making changes to your landscape. There are many things to consider and many questions to be answered when planning a landscape. How will you use the area? How will you get from one area of the garden to another? And how often will you walk this path? In which areas would you choose to linger? What views would you like to screen and what views would you like to frame? What elements of your own property would you like to hide (garbage cans, heat/air units, automobiles, etc.). Does water pool in areas? Does the evening sun come too brightly through the den window?

When the above questions (and more) are answered, the solutions are often straightforward, but sometimes confusing, as there is usually more than one way to solve a problem. Traffic flow, outdoor living areas, and drainage issues should be resolved first. Choosing plants comes near the end of the design process. When you are finally at the stage of considering plants, research on the cultural requirements (wet or dry; sun or shade, etc.) must be done. Mature size of the plants should be considered since a planting that matures at 12’ used as a foundation planting under a window will surely be a maintenance problem. Garden design, unlike interior design, is not static but ever changing. Relative sizes of plants change over the years as slower-growing woody plants outgrow their herbaceous neighbors. As larger plants mature, areas become shadier, often requiring some changes in under plantings.

Understanding your needs for use of the space and having knowledge of the plants you use will reduce the risk of making mistakes like placing large-maturing plants in too small of an area or making paved areas too small or in the wrong place. Plants and hardscapes can be expensive and removal of either is even more expensive.

Seems that spring will never arrive this year. We have not had a day above 55 degrees in several weeks. But that does not mean we cannot garden!
If you can bear the cool weather (and wind), now is a good time for many gardening chores. Cut back any perennials that have dead foliage. If broadleaved evergreens need cutting back (see previous posts on pruning) it’s best to do that now, before they put forth energy in new leaves.

It’s also not too late for planting. Just remember to water pants in well and top them off with a light layer of mulch. They will need supplemental water during dry periods until establishment.

The first question I ask a client who want a tree pruned is, “what do you want to accomplish by pruning (is it too large, is it misshapen, does it have dead limbs..?)” Most often, the answer is, “they just need pruning”. Usually, the best option for a tree that has outgrown it’s space is to remove it and replace it with a smaller-maturing tree. This is why proper planning is so important. Topping is unattractive and compromises the health of the tree. However, trees can be pruned, by selective removal of branches, to preserve health and appearance and to prevent damage to property and humans.

Building scaffold branches and a strong central leader should already have been done before a tree is purchased so will not be addressed here. The first step should be to remove any dead, dying and diseased branches. Also remove any branches competing with the central leader . Fiddlers (rubbing branches) should be removed, as should any inward-growing branches. Remove any low-hanging branches that interfere with vehicular or pedestrian clearance. Occasionally, a tree may need to be thinned to allow more air circulation and reduce wind resistance.

All cuts should be made just out from the branch bark collar. Cutting flush with the trunk creates a larger wound that will not callus over. This often leads to rot that the tree cannot wall off, creating cavities that become hazards later. Conversely, leaving a stub creates an area for harboring pests, is aesthetically unappealing, and, again can lead to rot and cavities in the future.

For limbs too large for loppers, make three cuts. The first cut should be made from the underside, only 1/2 through the branch and about one foot out from the branch crotch. Make a second cut from the top just outside the first cut. After the limb is removed make a final cut just out from the branch bark collar.

Pruning large trees can be dangerous and costly. Always use a Certified Arborist when pruning large trees.

Here’s a helpful link from the horticulture department at NCSU:

http://www.ces.ncsu.edu/depts/hort/consumer/factsheets/trees-new/text/pruning.html

For pruning caney shrubs (forsythia, spirea, nandina, mahonia….) the principle is simple. Prune from the base of the shrub. Remove about one-third of the oldest canes and any weak or crossing canes, taking them all the way to the ground. For flowering shrubs, this should be done just after flowering to prevent removal of next season’s flower buds. This method assures flowering is maximized (since all canes are young and vigorous) while the form of the shrub is maintained.

Boxwood should need very little pruning if the correct one is chosen for the correct space. Unless grown in heavy shade, they are naturally dense. However, an occasional, light shearing will keep them in shape. If shearing is done regularly, thinning will also be needed (see blog on “Pruning Formal Hedges”).

Occasionally, a client has overgrown American boxwood that they cannot bear to remove. Proper reduction pruning takes two to three years since boxwood may not recover from loosing too much top growth suddenly. Using sharp loppers or hand saw, remove up to one-third of the growth back to a branch crotch. One-third more can be removed each year until the proper size is reached. This leaves an unsightly plant for several years but works to reduce the size and save the plant.

Sheared hedges are formal hedges. They can be very attractive. They can also be pretty boring or even absurd if they do not match the larger landscape. Most homes in the Southeastern U.S. are not best complimented by formal hedges. However, if sheared, formal hedges are what you need, thinning should be done along with shearing. Repeated shearing causes thick branching ( I have seen some that a golf ball could not penetrate!), which inhibits sunlight and airflow; conditions that foster buildup of insects and disease. Use sharp hand clippers to remove branch clusters back to a branch crotch. This is a little scary for some since it creates small gaps in the smooth hedge. The effect is an airier look and a situation that is not so conducive to pests.

When shearing, taper sides outward from the top. It is important that the bottom flare outward slightly so that the bottom limbs will not be shaded and die, creating a ‘lollipop’ hedge.

For drastic size reduction, most Japanese and dwarf yaupon hollies can be pruned to within a few inches of the ground and recover nicely. This is best done in early spring so the plant will not be bare for very long. They will need a second (or even third) pruning by summer to encourage branching. Do not prune boxwood this way. Boxwood are about the only shrub that can be killed by severe pruning or pruning at the incorrect time.. More on that next week…

This is the first of several posts on pruning. I was asked again last week about pruning hydrangeas. There is much confusion about when and how to prune.

First, know whether the species you are pruning blooms on old wood or new wood. The easiest way to know this is by noting bloom time. If the plant blooms before July (H macrophylla, serrata, quercifolia), it blooms on old wood. If it blooms later in the summer (H panniculata) it is blooming on new wood. The best time to prune any flowering shrub in order to maximize next year’s blooms, is just after blooming.

Prune new-wood blooming hydrangeas either all the way to the ground, back by a third, or remove 1/3 of oldest canes and tip prune (whichever you find least unattractive-I have a difficult time finding any redeeming aesthetic quality in this shrub during the winter months). The idea is to have a lot of new growth since the old wood is not very productive for flowering. This pruning can be done from fall through spring before new growth begins.

Prune old-wood blooming hydrangeas by removing 1/3 of oldest canes (these are generally the scraggly, crossing canes that are unattractive) all the way to the ground and then pruning the tops back to 1/2 (flower buds are formed all along the stem but do not develop unless the terminal is removed.

Next week I’ll post on pruning formal hedges.

So why IS fall the very BEST time for planting? Two reasons: root growth and water availability.
Roots will continue to grow during warm fall days so when dry weather arrives next summer, the transplant already has established a few roots in it’s new home.
The number one cause of loss of newly planted plants is inadequate water. In eastern North Carolina, our soils usually are moist enough in winter to support most plants without having to give supplemental water. Deciduous plants need very little water in winter anyway since they have no leaves to transpire water. This does not mean that we don’t need to water newly-planted things in fall and winter. Always be sure to water any new transplant thoroughly to remove air pockets in the planting area. Also, broadleaved evergreens will loose water in winter and are especially vulnerable during long periods of cold when the ground my be frozen. Therefore, it is important to water newly transplanted broadleaved evergreens before a long-term hard freeze.

Fall is for planting and so is spring! Today I am throwing out a few thoughts on that subject.
Putting the right plant in a space is the most important part of the planting process. Researching light and water requirements as well as hardiness are all important considerations for success of a planting. Also, know the mature size of a plant! This will not only minimize maintenance (pruning) but will also help to avoid the need to rip the entire planting out years down the road, since some plants do not respond well or look good if heavily pruned. Be sure the plant is not invasive (see Blog-March 2011). Other considerations in the planning stage are plant color, texture, and overall form.
After plants are researched and chosen, prepare the planting area by removing all unwanted plants (broadleaved weeds, grass, and woody plants). I usually do this with glysophate and tillage but deep tillage and solar sterilization can work in many situations. Be thorough as removing weeds once the area is planted is much more difficult. Do not use non-biodegradable groundcovers (“landscape fabric”). This promotes a shallow root system which makes your planting more susceptible to drought, among other things. Newspaper or other degradable material if fine.
Amend the planting area with organic matter if the soil is very clayey or sandy. This improves water-holding capacity, nutrient supply, and soil structure.
In clayey soil, plant woody material with soil ball one inch above existing grade. For loamy or sandy soil, and for herbaceous material, plant even with existing grade.
Mulching the soil after planting will help reduce weeds, evaporation, and soil temperature fluctuations. Then….don’t forget to water! Water well at first to reduce air spaces in the soil. After that, keep the soil evenly moist (not wet) throughout the growing season.