Mount Baldy & Citrus Trees

Rancho Cucamonga

• Rancho Cucamonga, California, is located near the base of Mount Baldy and, according to the city's official website, was once home to groves of citrus trees. The majority of citrus tree groves in Rancho Cucamonga were in the Alta Loma community, located is in the northwestern corner of the city. Although urban development replaced many of the groves, some of Alta Loma's neighborhoods feature citrus trees in the yards of their residences. Urban development in Alta Loma occurred in the early and mid-20th century, when Rancho Cucamonga annexed the community. Most of Alta Loma's citrus trees are seen north of Banyan Street.

Environment

• Citrus trees require hot, dry climates to flourish. The U.S. Department of Agriculture's Hardiness Zones 9b and 10a are capable of facilitating citrus tree growth. Rancho Cucamonga and Alta Loma are located in USDA Hardiness Zone 9b. The minimum temperatures for trees growing in Zones 9b and 10a range between 25 to 35 degrees Fahrenheit. Citrus trees are capable of growing in Zone 9a, but are in danger of being exposed to winter frosts in these areas. Providing additional heat, such as Christmas lights underneath tree coverings, is effective if unexpected frosts come in Hardiness Zone 9b.

Cultivation

• When growing citrus trees, gardeners must place their trees in well-drained soil. The ideal soil allows water to run off to prevent too much moisture surrounding the citrus tree. Also, citrus tree soil should have appropriate internal drainage, or the ability to prevent too much moisture from surrounding the tree's roots. Gardeners plant citrus trees at least 6 to 8 feet away from buildings, septic tanks and sidewalks. Citrus trees need full sunlight for the best growth. These trees require watering two or three times during the first week after planting. After the first week, water the tree once or twice per week for approximately a month.

Varieties

• The two primary types of citrus trees found in the Rancho Cucamonga area are oranges and lemons. Orange trees (Citrus sinensis) grow up to 30 feet tall and were introduced into Southern California by Spanish explorers during the 18th century. Valencia is the most common orange tree cultivar in southern California and its fruit ripens in April and May. Eureka, Lisbon and Meyer lemon trees are the three most common lemon varieties in Southern California. Lemon and orange trees have low frost tolerances, but do not require high heat to ripen. Meyer lemons are usually the juiciest of Southern California's lemons.