By Marc Hess, Editor Gardening South Texas
With over 2,600 palm tree varieties to choose from, only a handful have have the best chance of surviving the “new” Texas winter weather patterns. The following is a comprehensive guide to help you select the most hardy palms for your landscape.
Palm trees give Texas landscapes an interesting, almost enchanting aesthetic. With their cool tropical vibe, their soothing colors and breezy patterns, palms are being deployed more extensively as ornamental plants in a greater climatic range throughout Texas. No longer confined to the coast, numerous palm tree species grow in Texas without much trouble. Two of them, the Dwarf Palmetto and Texas Sabal Palm, while not a native plant, even grow in the wild. Palm trees are known to withstand powerful winds, they require little attention once established and people with no gardening experience can easily grow them. But, while many palm tree varieties are wind-resistant, far fewer are cold-resistant.
Texas is growing increasingly vulnerable to mid-winter cold snaps. Historically, a normal Texas winter would have only given us a couple of days that were entirely below freezing and only a few nights when our thermometer dipped to the freezing point.
This is not so in the last few years. While the average winter temperature may be the same, we have now come to expect random mid-winter cold snaps that will leave us buried in ice and week-long freezing temperatures that last the whole week.
Harsh winter weather hits the tropical trees the hardest. Unlike hardwood trees that sprout new growth from multiple spots, palm trees only grow new leaves from one spot—the heart. The palm heart sits right in the center of the tree’s canopy, and if it’s hit with harsh cold, the damage trickles down to all the future palm leaves growing from it.
A hard freeze will leave your palm fronds brown and drooping, a terrible sight. But you will not be able to tell from the looks of it if the heart is dead. It’s quite difficult, even for the most experienced arborist, to predict the future of a freeze damaged palm.
You may remove fronds that are completely brown to improve aesthetics but there is nothing that you can do to improve your palms chances of survival. If it’s dead, it’s dead—if it’s not it’s not.
Palm fronds do not grow quickly. You will have to wait until April to know if your palms have survived. Your palms won’t show any new growth for months after the freeze damage is done. Even if leaves are mostly brown, any sign of green could mean the tree has a chance at survival. When your palm shows green at the very top or green sprouts at the base you can provide a moderate amount of water and a small amount of organic fertilizer that incorporates micro-nutrients like iron, manganese and magnesium. Be careful not to overwater. The quickest way to kill palms (and other heat tolerant woody perennials) is by giving them too much water. Trust nature.
Palms are tough. Eventually your palms may return to full beauty. It may take about six to eight months, but have patience and they’ll likely rebound. After the Great Texas Freeze of February 11 to 20, 2021, when even the southern part of our great state spent eight consecutive days below 32°F and Dallas plunged to a low of -2°F, arborists in San Antonio expected they would lose almost all of their Mexican fan palms (90%) and cold-tolerant Sago palms (70%). As it turned out over half of them survived.
Choose Your Palm Tree Wisely
As with all other plants the best way to assure the longevity of your palm is to choose a palm tree that is most suitable for your area.
SAGO PALMS
Sago palms are a popular, slow-growing tree due to their small stature and easy upkeep requirements. The secret to their cold hardiness is that they are not, technically, a palm tree at all. They just look like one. They are cycads, a group of plants that have been around since prehistoric times. The tree can grow up to 10-feet tall and has a large, round trunk with a crown of stiff, feather-like fronds. Unlike many plants, they do not flower, rather they create large, cone-like structures instead. They are easy to grow indoors as rugged houseplants or outdoors in containers in warm areas. Don’t let the mature height of these plants frighten you off. These slow-growers take many years to reach their final height.
TEXAS SABAL PALM
Stately and robust, Texas Sabal palm is a native to our big state that can grow up to 50-feet. The canopy of a mature Texas Sabal palm may be up to 25-feet across with a crown of fan-shaped fronds at the peak of the huge, thick trunk. The fronds range in color from light green to emerald green, depending on whether they grow in an area with shade or full sun. Another distinct feature is the crosshatch pattern on the trunk and the limited number of leaves (usually 10 to 25). Each leaf features 80-115 leaflets with threads hanging along the margins. Tall and wind resistant, the Texas Sabal Palm is cold hardy to 16°F.
WINDMILL PALM
If you are searching for a versatile Texas palm tree, the Windmill palm is a good bet. A mid-sized palm with a single trunk produces a canopy of lustrous green fan fronds that works well as a framing tree or an accent around the shady borders of your yard. Just be sure that your Windmill palm is on well-draining soil. It is cold-hardy and highly tolerant to numerous climate types, including humidity, heat, and moisture. The best part is that it has a moderate growth pace, meaning you won’t have to wait for too long to have matured palms in your yard.
MEDITERRANEAN FAN PALM
The Mediterranean Fan palm proudly holds the reputation as the hardiest of all palms. With a small, stocky appearance, 15-feet at maturity, it wears a canopy with dark green fronds that makes it the perfect tree to grow under power lines. This palm also grows slowly and develops suckers upon maturity. You can transplant the suckers to grow solitary trunked palms or allow the tree to create a grouping. Some have said that Mediterranean Fan palms are cold hardy to as low as 0°F but I wouldn’t want to test that theory in my yard.
PINDO PALM
The Pindo Palm is the most cold-hardy feather palm, bearing up well in freezes of 14°F degrees and lower. Pindos handle the harsh north Texas winters with little or no damage. They feature a stout, thick trunk with distinctive silver-green arching fronds spraying from the top. They are an excellent choice for growing in containers, make attractive deck, patio and poolside palms. They are a short stature accent palm. The foliage leans to the blue-green or silvery-gray color.
DATE PALMS
Date palms, which produce edible fruit, can be seen across South Texas and throughout the more arid and desert climates of Arizona and California. These very clean, beautiful, resort-style palms are a great choice for parking lots, to line a long drive or road, or to anchor a planting bed. Elegant and highly wind tolerant Date palms have been known to recover from 14°F of damage.
CABBAGE PALM
The Cabbage palm is a warm-weather tree that grows well where the humidity levels and temperatures shoot during the summer months. It thrives along the gulf coast but you don’t see many in Central or Northern Texas. It can tolerate brief temperature dips of up to 10°F. Cabbage palms can grow up to 40 feet or taller. Their trunks have a uniform diameter from the base to peak, where the fan-shaped fronds are held in place by stiff, woody stalks. These fronds spread around the top to give the branchless tree a nice “palmy” look.
CALIFORNIA FAN PALM
The California Fan palm, also known as the Desert Fan palm, does not score high in its cold tolerance. However, we have seen the tree grow in Dallas, Fort Worth, and parts of North Texas with a bit of care. It can survive temperature dips in winter and humidity and dry conditions during hot summers. One of the major perks of this palm tree is that it has a fast-growing rate. A mature tree will have a wide, smooth trunk and a large crown of pale green fan-shaped leaves that grow three to six feet long. Moreover, the California fan palm can grow to an impressive height.
DWARF PALMETTO PALM
The Dwarf Palmetto palm has no trunk at all so it only gets up to the height of two to seven feet tall. The fan-shaped fronds grow directly from the ground and have slight differences in size.
It is pretty hardy for a warm-weather tree and doesn’t sustain much damage through occasional winter cold snaps, especially once it matures. Its only worthy rival in terms of cold-hardiness is the Needle palm. The Dwarf palmetto can thrive in just about any part of Texas without much trouble. It is also tolerant to hot, humid, and heavy moisture conditions.
MEXICAN BLUE FAN PALM
The Mexican Blue Fan palm is native to northern Mexico and Baja California and is a popular palm in many southwestern states. It is a cold-hardy palm species that can bring unique aesthetics to your yard. This slow-growing tree has striking bluish-silver fronds, and each frond can have a width of up to 10 feet. The Mexican Blue Fan palm grows up to 50 feet tall and spreads to 20 feet wide. This tree can tolerate temperature dips of up to 10°F. When the winter temperatures fall below double digits, you may have to winterize the fronds and protect them from damage. The Mexican Blue Fan palm tree grows best when planted in warm, sunny spots.
Plant Your Palm Trees When Its Warm
Plant your palms when the soil is warm. Palms have a fibrous root system, with each root fiber growing from a single root collar. When part of the root is severed by moving, it dies back completely. Severed roots must be replaced by new roots if the plant is to survive.
Warm soil temperatures are needed to encourage this new growth or the plant may rot before growth begins. That means that balled palms should be moved in warm weather. A good rule of thumb is to plant balled palms before September 1st in all but the Lower Rio Grande Valley.
Palms prefer well-drained soil, rich in organic matter and with adequate water and nutrient-holding capacity. Loams and clays with good subsoil drainage are preferred over sands or soils with impervious pans or parent material.
Young palms cannot survive as many sub-freezing hours as older palms which have developed protective “wood” around the vascular bundles and the central “shoot.”
FUN FACTS
Palm trees are divided into three categories by the type of fronds or leaves:
➢ Palmate leaf palms have lobes fanning out from a common point. The structure resembles a fan or open hand, with fingers stretching out from the palm.
➢ Pinnate leaf palm, derived from the Latin “pinna” or feather, has individual leaflets branching out on both sides of a common axis resembling a feather.
➢ Costapalmate leaf is a cross between a palmate and pinnate shape.