1. Managing Landscape Palms
Linda Seals
agente de extensión agricola
el condado de Brevard, Florida
Parts of this presentation were adapted from a presentation created by Kim Gabel, Horticulture Extension Agent, Monroe County UF-IFAS Extension.
Managing Landscape Palms

2. Palm Anatomy Monocot Palmate, costapalmate, or pinnate fronds
One central growing point - bud

3. Palm Stem
Vascular bundles concentrated to outside of stem (decreasing towards the center).
Relative distribution of vascular bundles between inner and outer regions varies between species.

4. woody trunk vs. palm stem

5. Palm Stem Stem surface varies among species
Phoenix (knobby) vs. Cocos (smooth)
All palms with a crownshaft are self-cleaning
Roystonea, Hyophorbe, Adonidia merrillii, Wodyetia bifurcata, Dypsis sp.
Other palms may or may not be self-cleaning
Phoenix spp., Sabal spp., Washingtonia spp., Syagrus spp., Livistonia spp.
Cannot determine age of palm based on stem height or diameter

6. Palm Leaves
Number of leaves produced is function of species and environment, especially nutrition.
In general, for every visible leaf, equal number of leaves in development in bud (heart = apical meristem)
Damage to bud affects leaves that will emerge later

7. Longitudinal cross-section through bud

8. Right palm, right place Palm height Growth rate Hardiness Zone
Salt tolerance
Light requirements
Nutritional needs
Human hazards
Major Pest problems
Major Disease or Physiological problems

9. Environmental Effects
Light
Water
Wind
Lightning
Powerline Decline
Herbicides

10. Parlor Palm Chamaedorea elegans
Light
Palms growing in full sun require higher fertilization rates than shade grown palms in order to maintain dark green color and growth rate.
Parlor Palm Chamaedorea elegans
Sunburn: large necrotic areas on upper leaf surface

11. Water
Prolonged drought causes growth reduction, leaf desiccation, starting with leaf spear.
Poor drainage causes wilting and poor growth.
Most established in ground palms are drought resistant.
Geonoma sp.
Cocos nucifera

12. Salty Water quality problems
Water soluble fertilizers or saltwater intrusion.
Foliage appears wilted, leaf tip necrosis, especially old fronds.
Salt damage can injure root tips.

13. Salt Spray Wind Damage
Extensive necrosis, rinse foliage with fresh water
Salt wind tolerant palms:
Allagoptera arenaria
Coccothrinax spp.
Cocos nucifera
Hyophorbe spp.
Pseudophoenix spp.
Serenoa repens
Thrinax spp.

14. Hurricane Wind Damage

15. Lightening Fatal - sudden collapse of the crown
Longitudinal splitting or dark color streaks on the trunk
Trunk bleeding from breaks or spots scattered throughout trunk
Protection of valuable palms with lightning grounds

16. Powerline Decline
Palm fronds within 1 to 2 feet of powerlines exhibit yellow tip and dieback.
Prevention: do not plant tall growing palms directly under or close to overhead lines

17. Herbicides
Arrested development of new leaves, when leaflet emerges show necrotic blotches, tip necrosis “accordion leaf” and stunting
Symptoms may not become visible until 7 to 9 months after application
Roystonea regia (Cuban Royal Palm)

18. pH
Alkaline soils occurs where soils or the fill is derived from parent material high in limestone, such as the shell and/or coral rock
Alkaline soils "tie up“ essential nutrients making them unavailable

19. Common Landscape Deficiencies
Turfgrass: Nitrogen, Iron
Broadleaf plants: Magnesium, Iron, Manganese, Potassium, Nitrogen
Palms & other monocots: Potassium, Magnesium, Manganese, Boron, Nitrogen, Iron
Turfgrass and broadleaf plants are susceptible to some of the same nutrient elements as palms in Florida landscapes. Thus, any fertilizer that provides sufficient nutrients for palms will also provide sufficient nutrients for turfgrass and broadleaf plants

20. Potassium (K) Deficiency
Most important limiting element in palms
Translucent yellow-orange or necrotic spotting of foliage
Marginal and/or leaflet tip necrosis
Most severe on oldest leaves and towards tips of affected leaves
Potassium deficiency is by far the most important limiting element in palms grown in the field or landscape, not only in Florida, but throughout the palm-growing world. It was only in 1988 that we determined the identity of this ubiquitous problem in landscape palms. Symptoms are quite variable, being affected by the species, and by the severity of the deficiency.