PALMS AND CYCADS
This group of plants is especially useful in the development of the tropical effect in landscaping beautification Table 1. The true palms all belong to the botanical family Palmaceae. The cycads, including the Sago palms and the Zamia, belong to the family Cycadaceae. Palms of the hardier types will survive in many parts of Texas, but forms such as Washingtonia robusta, Phoenix canariensis, Cocos australis, Phoenix Roebelenii and Cycas revoluta thrive to perfection in the Lower Rio Grande Valley.
The stately fan palms and the graceful Phoenix and Cocos palms may be used for avenue planting, in group plants at the end of roads, or to give height to mass plants of the more dwarf types of plants. The dwarf forms such as Cocos australis, Phoenix Roebelenii and Cycas revoluta are especially useful for small group plants.
Most palms, with the exception of the Royal and Coconut, are sufficiently hardy to be used freely in landscape work in the Lower Rio Grande Valley. This group of plants can endure considerable drought but do their best when given good cultural care and adequate amounts of water.
All bloom in the spring, although the cream colored bloom is relatively inconspicuous and therefore unimportant.
The principal pest of young palms is the giant beetle which burrows down beside the young plants and then tunnels into the inner tissues. Beetle damaged palms are considerably dwarfed and frequently die as a result of the injuries. These beetles are controlled by flooding the burrows with a pyrethrum solution.
Pruning is probably the biggest job connected with the care of this group of plants.
Chrysalidocarpus (Areca) lutescens. Golden Feather Palm. A palm useful for porch or patio planting. It produces a slender, ringed trunk and graceful curving pinnate foliage with golden yellow stems. Suckering freely at the base, it produces a bushy effect. This palm is very tender to cold.
Cocos australis. Dwarf Blue Palm, Australian Palm, Pindo Palm. A rather dwarf palm which produces graceful, recurved, blue-green, pinnate leaves. The bright yellow, edible fruits are borne in heavy, ornamental clusters. This palm is well adapted to conditions in this region.
Cocos nucifera. Coconut Palm. Although this palm is very valuable for its ornamental pinnate foliage and its edible "nuts," it is too tender to cold to be grown in this region except in sheltered locations along the coast.
Cocos plumosa. Queen Palm, Plumy Coconut Palm. A tall, slender palm which produces a smooth light gray trunk and graceful, feathery, dark green leaves. Although somewhat tender to cold and occasionally chlorotic, this palm can be grown successfully in the Lower Rio Grande Valley in sheltered locations.
Cycas circinalis. Queen Cycad, Fern Sago. A large cycad which attains a height of six to eight feet. It is symmetrical in its habit of growth, producing graceful, bright green, pinnate foliage. The foliage is subject to sun scald, and it is recommended that this plant be given a shady location.
Cycas revoluta. Dwarf Sago Palm. A dwarf plant of stiff, symmetrical appearance. It produces very dark green, stiff, pinnate leaves which have commercial value in floral decorations. Well adapted, and easily propagated by offshoots.
Erythea armata. Blue Fan Palm. A very slow growing palm whose stiff bluish-gray "fans" are covered with a powdery bloom on both surfaces. Well adapted.
Howea Belmoreana. Kentia Palm, Curly Palm. A small palm useful for porch or patio. It produces slender, graceful, dark green pinnate leaves at the top of a small, upright trunk.
Latania Commersonii (Livingstonia chinensis). Patio Palm, Chinese Fan Palm. A dwarf fan palm which produces bright green, fan shaped leaves and a slender dark brown trunk. This palm is suitable for porch or patio use only, since it is very tender to cold and subject to wind burn.
Oreodoxa (Roystonea) regia. Royal Palm. A tall, slender palm which produces a smooth light gray trunk and a head of graceful, bright green, pinnate leaves. This palm is too tender to cold to be used except in a sheltered location.
Phoenix canariensis. Ornamental Data Palm. A large, spreading palm which produces drooping, dark green, pinnate leaves and ornamental fruit clusters. It is well adapted and useful in specimen, group or avenue plantings.
Phoenix dactylifera. Data Palm. A large spreading palm which produces gray-green, pinnate leaves that are rather stiff and upright, giving the plant a less pleasing appearance than the Ornamental Date. However, it is well adapted and can be used where a large specimen plant is needed. If edible fruits are desired, it is recommended that offshoots from superior fruiting plants be secured.
Phoenix reclinata. Leaning Palm. A spreading Phoenix palm somewhat resembling the Ornamental Date but having a tendency to form bushy clusters of offshoots. The palm presents a better appearance if the offshoots are allowed to remain. This plant has proven to be quite slow growing and somewhat tender to cold.
Phoenix Roebelenii. Pigmy Date Palm. A very dwarf palm which produces a small, upright trunk, and a head of very fine, fern-like foliage. It is quite tender to cold, and is most useful in patio plantings.
Sabal Blackburnia. Blackburn Palmetto Palm, Giant Palmetto Palm. This is the larger growing species of palmetto which is native to other parts of the state.
Sabal texana. Texas Palmetto Palm. The Sabal palms are well adapted and should be extensively used. The native S. texana is an upright fan palm producing blue-green foliage. The trunks of the young palms are most attractively laced or "booted" with the green leaf petioles which remain firm and green on the palm trunk for several years. This palm is highly resistant to wind and cold damage. It is supposed to be the first palm tree sighted by Europeans on the North American continent, and was responsible for the first naming of the Rio Grande, "Rio de las Palmas." The Palm Grove near Brownsville is composed of these native palms. Its fruits are considered edible and are sold as fresh fruit in the Matamoras market.
Trachycarpus Fortunei (Chamaerops excelsus). Windmill Palm. These upright fan palms seldom reach a height of over ten feet. The "fans" are set windmill-fashion on the trunk. The trunk is covered with coarse, loose, brown fiber. Well adapted.
Washingtonia robusta and filifera. Washingtonia Fan Palm. Both of these species of tall fan palms grow in this region, and are well adapted. W. robusta, the taller species, is the most commonly planted. The leaves are cleft 2/3 to the base, and the petiole margins are completely armed. W. filifera produces leaves which are cleft almost to the middle and the petiole margins are armed about half the length. This species is more wind resistant.
Zamia integrifolia, Z. floridana and Z. pumila. Zamia, Coontie, Comptie. These dark green, dwarf cycads are very ornamental, being especially useful as foreground subjects in palm plantings. There are several species of Zamias native to Florida, some of which are collected by the Indians as a source of food and income. The fleshy underground roots produce the arrowroot of commerce.TABLE 1. PALMS AND CYCADS
*Not grown on the Experiment Station.
Cold Hardiness: 9-Hardy; 5-Fairly Hardy; 1-Tender
Adaptability: 9-Excellent; 5-Fair; 1-Poor
Desirability: 9-Desirable; 5-Fairly Desirable; 1-Undesirable.
Name Mature size Cold Hardiness Adaptability Desirability Notes Height
Spread (feet) Chrysalidocarpus lutescens
Golden Feather Palm
10-15 3- 4 2 6 9 Useful as indoor subject Cocos australis
8-10 6- 8 9 9 9 Excellent dwarf palm Cocos nucifera
20-25 15-20 2 3 1 Useful only on the coast Cocos plumosa
20-25 10-15 5 7 8 Useful as specimen Cycas circinalis
6-15 6-10 3 7 6 A shade loving, dwarf, palm-like plant Cycas revoluta
2- 6 5- 6 7 9 9 A symmetrical, dark green, dwarf plant Erythea armata*
Blue Fan Palm
10-20 4- 8 9 9 9 Desirable, small, fan palm Howea belmoreana
3 2 2 9 9 For indoor use Latania Commersonii
5-15 5-10 2 8 8 Indoor use only Oreodoxa regia
50-70 10-15 1 3 1 Very tender to cold Phoenix canariensis
Ornamental Date Palm
25-30 20-25 9 9 9 Extensively used in avenue planting Phoenix dactylifera
25-30 20-25 9 9 2 Very subject to foliage disease Phoenix reclinata
20-25 15-20 9 6 5 Slow growing; suckers freely Phoenix Roebelenii
Pigmy Date Palm
2- 4 2-2 1/2 4 9 9 Very desirable, dwarf date palm Sabal Blackburnia*
25-30 8-10 9 9 9 Well adapted native palm Sabal texana
15-25 8-10 9 9 9 Native palmetto palm Trachycarpus Fortunei*
6-20 6- 8 9 9 9 Very attractive, small, fan palm Washingtonia filifera*
Calif. Wash. Palm
40-50 8-10 9 9 9 Very similar to W. robusta Washingtonia robusta
Mex. Wash. Palm
50-100 8-10 9 9 9 Very popular avenue palm Zamia floridana Coontie 1- 1 1/2 1-1 1/2 8 9 9 Much smaller than sago palm
Ornamentals for the Rio Grande Valley