Pronounciation: CI-trus li-MON

Hardiness zones:
Sunset 12-24
USDA 9-11

Landscape Use: Accent, edible gardens, residential fruit tree, mesic and oasis landscape design themes, attracts bees.

Form & Character: Upright, rounded, symmetrical, domestic, colorful, abundant.

Growth Habit: Evergreen, woody perennial large shrub to small tree, moderate growth rate to 20-feet tall with similar spread.

Foliage/Texture: Medium green, glaborous and leathery leaves are oblong, elliptical, or oval, tapering to a blunt tip, 3-inches long, 1.5-inches wide, petiole wings are slim, lamina midvein is prominent, sometimes sharp, stipular spines are present; medium texture.

Flowers & Fruits: Flowers are borne in small clusters in leaf axils, flower buds are purplish, but open flowers have five distinct white petals, up to 2-inches across, highly fragrant. Flowers are hermaphroditic (has both male and female organs), self fertile, pollinated by bees; fruits are a hesperidium berry, globose to oblong, 3- to 5-inches long, fruit apex occassionally nippled, exocarp ripens to yellow with smooth to bumpy rinds dotted with oil glands, endocarp having 8-10 segments (carpels) each containing a single seed.

Seasonal Color: Yellow fruits typically ripen in late fall and winter, seasonal color derived from fruits is cultivar specific.

Temperature: Cold hardy to 26^oF and heat intolerant above 118^oF. Significant heat stress injury (leaf yellowing and necrosis) occurs above 112^oF, especially if located in full western sun.

Light: Full sun to filtered shade or some shade from western summer sun, no full shade.

Soil: Tolerant, but well-drained soils is essential. Maintaining adequate to optimal soil fertility levels is crucial for successful culture of lemon. Generally, lemon like other citrus will need to be fertilized with a balanced, complete fertilizer containing micronutrient supplements (Fe, Zn, and Mn) three times each year (in late January before flowering, mid May to encourage summer fruit development, and in early September for final fruit sizing and ripening).

Watering: Moderate and consistent patterns of supplemental irrigation are neccesary for successful desert culture, but irrigation frequency and duration varies with time of year and soil texture. In general, flooded, berm irrigations are superior (less accumulation of soil salts in the rhizosphere) to drip irrigation.

Pruning: Only infrequent, 'light' pruning to encourage a dense canopy of foliage is recemmended. Pruning strategies should always NOT incude crown raising because all Citrus taxa are HIGHLY prone to sunscald injury if trunks are exposed to direct summer sunlight.

Here's a sustainable tip: If the 'Horticultural clods of Phoenix' (aka 'Hort clods') have wandered (like migrant nomads) into your yard and 'lolly popped' your lemon trees by raising the crown base to expose their trunks to direct sunlight, then promptly respond by painting the trunk surfaces with a mixture of white flat latex paint and water (1:1 ratio) to protect the exposed trunks from summer sunscald injury.

Propagation: Softwood or semi-hardwood stem cuttings, grafting, budding.

Disease and Pests: Citrus are prone to numerous, well-documented, mostly soil-derived, biotic and abiotic pressures.

Additional comments: Citrus limon was introduced into Spain and North Africa sometime between the years 1000 and 1200 AD and was later further distributed throughout Europe by the Crusaders, who found it growing in Palestine. Around 1500 AD, lemon fruits were first shipped to England from the trees growing on the Azore Islands. Today, lemon trees are an essential staple for any Phoenix residental backyard fruit tree collection. Lemon fruits are used in beverages and cooking, and also as a preservative due to its antioxidant properties. Other nutritional, medicinal, and pharmacological uses of lemon are legendary and well documented.

There are several wonderful lemon cultivars and hybrids that perform well in the lower Arizona desert.

These include:

• 'Eureka' - most common lemon cultivar, prolific fruit producer.
  
• 'Lisbon' - most dependable lemon cultivar for the Phoenix area.
  
• 'Meyer' - a hyrid cross between Citrus limon (lemon) and Citrus reticulata (mandarin), fruits less acidic.
  
• 'Ponderosa' - grows largest fruits.
  
• 'Variegata' (pink lemon) - with its variegated leaves and striated fruits with pink-colored endocarp, pink lemon is the most environmentally-senstive-to-heat lemon cultivar for Phoenix. Protection from western sun is mandatory for successful pink lemon culture.
  

Here's a culinary tip: Savy chefs will use lemon extract to tenderize meats, especially chicken, for that perfect, outdoor charcoal-grilling experience.