Crape Myrtle – A Southern Tree for Your Alpharetta and Roswell Yard
Lagerstroemia, known as crepe myrtle or crape myrtle is a tree that thrives in US Hardiness zones 7 through 10, making it a perfect choice for your Alpharetta or Roswell yard. The genus came to the US over 200 years ago and got its name from the Swedish merchant Magnus von Lagerstrom.
The most popular species is L. indica. It is a native of southern China and Thailand. For centuries, crepe myrtles have been grown in Asia as ornamentals.
Of all the southern trees and plants, crepe myrtles are among the most desired for their outstanding summer display of blooms and their brilliant fall colors. 72 Tree, Seed & Land Co. prepared an extensive article covering the characteristics, environment, and care these trees need to flourish and light up your landscape.
Are Crepe Myrtles Trees or Bushes
The Lagerstroemia genus contains approximately 50 species of trees and shrubs both deciduous and evergreen. So, this species can indeed grow as a tree or shrub, making it ideal for hedges, container planting, or even in groupings along your landscape.
Height – The L. indica species possesses cultivars and hybrids that remain under 5ft in height, some that reach 11 to 15ft in height, and those that tower over the others, reaching heights of 20 to 30ft.
Canopy – At maturity, the canopy can reach from 6ft to well beyond 15ft depending on the species.
Trunk – Crape Myrtles are known to have multiple trunks with beautiful bark which exfoliates in the winter months. Be cautious when pruning or working around these trees, their wood is somewhat brittle, and the trunks may easily crack when put under pressure.
Lifespan – When planted in full sun and fertile soil, Crepe Myrtles can live well beyond 50 years. In fact, dotted along the southeastern landscape, it is common to come across specimens over 100 years old.
Uses – Depending on the species, these trees work as shrubs, hedges, container plants, landscape groupings, and in some cities as street trees.
If you decided you prefer to plant an evergreen instead, visit 72tree.com/3-evergreen-species-alpharetta-roswell-yard/ for some great candidates.
Crepe Myrtle Tree Care
About two years after planting, these species become very tolerant to drought, heat, humidity, and will do well in nearly any well-drained soil. They become robust enough to resprout even after being completely frozen.
Crepe myrtles are low maintenance. However, you still need to do some planning before planting and a bit of upkeep as they grow.
Planting – Location is critical when planting crepe myrtles. Select a spot that has well-drained soil and gets full sun. Planting in partial or full shade will significantly reduce its ability to flower and may reduce its lifespan as well.
Crepe myrtles have a shallow and very fibrous root system which can extend 3 to 4 times the diameter of the canopy. As with all trees, the planting location should be at least 5 to 10 feet away from cement pathways, foundations, and sidewalks.
Pruning – Very little pruning is required. Improper pruning disrupts the development of a robust branching system and will leave your specimen deformed and vulnerable to weather, pests, and fungi.
If there is a need to prune, it should occur in late winter or early spring to correct the following:
• Removing crossed or rubbing branches.
• Removing suckers from the base.
• Branches growing inward (toward the center).
• Canopy thinning for better air circulation.
• Gradually remove side branches up to 4 or 5 feet as the tree grows.
• Reducing multi-trunk trees to a single trunk (not recommended).
Summer pruning can include:
• Removing old seed pods and spent flowers (removing them after the first bloom encourages further blooming).
• Removing small twig-like growth.
All crepe myrtle species bloom on new wood. The proper and minimal pruning of your tree will encourage this growth and promote a beautiful summer blooming season.
If you are pruning your tree because it has gotten too large for its location, you’ve planted the wrong species.
Watering – Provide newly planted crepe myrtles with a deep and thorough watering. Then, water your tree up to 4 or 5 times per week during hot weather or when planted in sandy soil. When the tree is dormant or during cold weather, your tree will need watering once per week.
Blooms – As previously mentioned, all crepe myrtles bloom on new wood. After the first bloom, removing the spent flowers will encourage further blooming in the season.
Tree Pests and Disease That Attack Crepe Myrtles
These trees like all others on your landscape are susceptible to infestations, disease, and animal damage. The best defense against these threats is to keep your tree(s) healthy, plant, prune, and water them properly and they will be less likely to suffer damage from the following:
Pests that infest crepe myrtles:
Japanese Beetle – This insect is approximately 1/2 inch in length, its body is oval and metallic green, and its wings are copper in color.
Larvae remain underground where they consume grass and young tree roots. Adult beetles feed on the tissues of the leaves and are most active on trees in full sun during the warmest part of the day.
A Japanese beetle infestation can cause severe damage to all of the trees on your landscape. Traps, pyrethrins, and neem oil can help curtail a beetle outbreak. However, this is an urgent situation which needs to be evaluated by a certified arborist.
Crape Myrtle Aphid – These insects are yellowish-green and have black spots on their abdomen. They measure from a sixteenth to an eighth of an inch in length.
Both nymphs and adults feed on the underside of the foliage causing it to droop and yellow leaf spots to appear. Buds, flowers, and branch tips can all be damaged as well from their feeding.
Sooty mold will appear on the leaves when there is an aphid infestation. This mold is a byproduct of the aphid’s excrement and will disappear once the outbreak ends.
Watch this video to learn how to eliminate aphids and “black” sooty mold on your crape myrtle.
When a crape myrtle aphid infestation occurs, apply a 2oz. to 1 gallon solution of molasses and water to the affected areas and release ladybugs around the tree. Neem oil is also very useful in controlling aphids.
Fungi that attack crepe myrtles:
Powdery Mildew – This fungus appears as a white powdery substance and can spread very quickly if not handled properly.
It is worth noting that trees planted in full sun are not typically bothered by this fungus.
To control powdery mildew, spray a fungicide on the affected area and its surroundings.
Sooty Mold – This mold has a tar-like appearance and is a result an aphid infestation (see above).
Bark Shedding – Don’t be alarmed. While it may seem that something has infected your tree, there is nothing wrong with it. Crepe myrtles, once reaching adulthood will naturally exfoliate their bark in winter months, revealing the magnificent color variations of its trunk.
Crepe Myrtles and Summer Blooms
If you are looking for an incredible addition to your Alpharetta yard or landscape, crepe myrtles are a must have. Besides being low maintenance, they will put on a colorful show every summer.
An added plus in the summer is when the blooms attract birds seeking refuge and nesting and offer their nectar and pollen to the bees.
3 Evergreen Tree Species for Your Alpharetta and Roswell Yard
The difference between evergreen trees and deciduous trees becomes very obvious in the fall. Evergreens stay green and keep their foliage, while deciduous trees typically change the color of their leaves before dropping them and going dormant.
Evergreen trees do drop foliage, just not all at once. Throughout the year, they will drop small portions of their foliage and grow it back. These trees do not experience a dormant period like their deciduous counterparts, but they do slow down in the winter months.
For those with an aversion to raking up leaves in the fall, the arborist at 72tree.com identified 3 evergreen tree species to enhance your Alpharetta and Roswell Ga landscape.
Of the North American native tree species, pine trees are one of the most widely spread and varied classes. Because of their ability to adapt and the ease to care for them, pines remain very popular landscaping trees from coast to coast.
Height – Within the pine family, some of the species can reach an astounding 150 feet tall and live to be more than 450 years old.
Crown Width – Mature pine tree canopies can stretch from 15 t0 30 feet in diameter depending on the species and the environment it is planted in.
DBH – When pines such as these reach maturity, their trunk DBH (diameter at breast height) can measure from 2.5 to 4 feet. As with most trees, there is just as much happening below ground.
Root System – As pines develop an extensive, deep, expansive, and invasive root system, they should not be planted within 20 feet of permanent structures like fences, underground utility lines, or homes.
Pest Problems – Bark beetles, aphids, and bagworms are a few of the pests that enjoy making a meal of pine trees. Mites and tree scale are also likely.
Disease – Some of the more common diseases that affect pine trees are needlecast, root rot, and pine wilt.
Pesticides and fungicides can be used to curb the progress of these pests and diseases. However, in cases of severe infestation and infection, an arborist should be called to evaluate the tree and what actions should be taken (including the tree’s removal if necessary).
This classic Southern beauty (magnolia grandiflora) is very distinctive with its wide glossy leaves and enormous fragrant white blossoms. When it comes to year-round beauty, there are few trees that can keep up with it.
Its full luxurious look has made it a popular ornamental around the world.
This tree, although evergreen will drop leaves throughout the year. Growing anything beneath this tree (including grass) is difficult due to its dense foliage casting full shade and its shallow roots.
Height – A magnolia tree planted in a location with rich soil, little to no obstacles for the root system, and good soil drainage can reach heights of more than 80 feet.
Crown Width – While this tree possesses a pyramidal to rounded crown at the top, its width can reach 30 to 40 feet at the base and mid section.
DBH – Adult magnolias can reach a DBH of 24 to 36 inches. To reach this size takes anywhere from 80 to 100 years.
Root System – The species itself is a deep rooted one. First to develop is a strong tap root, then as the tree grows, many sunken roots will grow down from the root collar, and as the tree ages, major lateral roots will grow. When planted in areas with a high water table, the roots will grow more shallow and outward.
The optimum soil for this species is a rich, well drained, and slightly acidic one. When planting a magnolia, add generous amounts of organic material to the soil for the best growing conditions.
Although magnolia roots are not considered invasive, when planted too close to sidewalks or foundations, they will eventually cause undesired cracking and buckling.
Pest Problems – Varieties of scale, aphids, striped mealybug, spider mites, and magnolia leafminers are all potential infestation culprits.
Disease – There are a number of fungi which cause leaf spots. For the most part, they are unable to cause any significant damage to adult magnolias.
As well, there are a number of Polyporus fungi and Fomes which can cause heart rot.
Again, pesticides and fungicides can be used to curb the progress of these pests and diseases. When a severe infestation or infection is detected, an arborist should be called to assess what actions should be taken.
Of all of the evergreen trees you could want in your yard, eucalyptus should be at or near the top of the list. This species is a fast growing, insect repelling, and gorgeous tree that adds beauty and practicality to whatever landscape it grows in.
For most, the image you get when you hear “eucalyptus” is a koala bear latched on to a branch, munching away at the leaves. You may be surprised to learn that only the koala, some possum species, and a select few insects are actually able to consume parts of this species. In large quantities, this tree’s secret weapon (cineole) is toxic.
It is the cineole aka: eucalyptol in eucalyptus trees that make up the greatest part of its signature aroma. Eucalyptus essential oil has been used for centuries in the treatment of respiratory ailments, as a disinfectant, and as an antibacterial or anti-fungal agent in medicine.
Height – Eucalyptus tree sizes vary. Their height at maturity can range from 30 to 35 feet for smaller varieties all the way to over 200 feet for the tallest of the species.
These trees must be planted away from physical structures. Mature eucalyptus trees are known to unexpectedly drop branches.
Crown Width – The eucalyptus tree species will typically grow tall and relatively slender, with mature crowns reaching from 12 to 30 feet in diameter. Many varieties of the species are able to reach much greater diameters as they age.
DBH – Adult eucalyptus trees can reach a DBH of 15 to 20 inches.
It is worth mentioning that this species is able to reach maturity within 10 years of growth. That’s less than half (in some cases less than a third) of the time it takes for the majority of other species to reach maturity.
Root System – This species quickly adapts to the soil it is planted in. In rich, fertile soil, the roots have no need to go deep. The tree is on a fast track for height and the roots will spread horizontally staying close to the surface.
In more nutrient deprived soil, the roots will dive deep for their food and moisture source. Counterintuitively, it is the eucalyptus planted in poor soil that grows to be the more stable and wind or storm resistant.
Pest Problems – Little to none (as long as the tree remains healthy). High concentrations of cineole in all parts of eucalyptus trees acts a natural insect repellant.
Two species of Australian tortoise beetles (family Chrysomelidae) (still isolated in the west) chew semicircular holes or notches on edges of eucalyptus leaves.
These beetles are able to remove most of a leaf’s surface, leaving only the midvein.The damage caused by these beetles is unsightly but not life threatening to the tree.
If a tree is stressed enough, an opportunity opens up for the eucalyptus longhorn borer. The female of this species lays her eggs on stressed trees, producing larvae that burrow their way to the cambium layer.
A heavily infested tree can die within weeks, which is due to the larval galleries girdling the tree and disrupting the flow of water and nutrients.
Infestations must be treated immediately. Because of the speed at which death can occur, an arborist should be called to evaluate the tree and determine what actions to take.
Disease – Canker, heart rot, and Phytophthora can infect a stressed eucalyptus tree. All three of these fungi attack and damage the tree from the inside.
Signs of infection are discolored leaves and in severe cases, splitting of the trunk. In any of these cases, the tree should be removed, destroyed (burned) and all equipment disinfected to prevent the disease from spreading to other trees.
Tree Care for Evergreens
As long as evergreens are planted in hardiness zones where they can thrive and get ample summer sunlight and winter shade (possibly on the north side of your property), caring for these trees is relatively simple.
Water them regularly and mulch around their trunk. This will keep them strong and winter injury resistant. Evergreens (when not mulched or watered well) can be severely injured by the drying effects of the sun and wind through winter months.
A major benefit of evergreens in your yard is that there is no bad season. Even during the coldest days of winter, your landscape will be filled with full, and vibrantly-green trees.