UCB-1 Hybrid Pistache

Pistacia atlantica x integerrima ‘UCB-1’

UCB-1 is the short name for University of California Berkeley #1 hybrid pistachio rootstock, invented by Dr. Lee Ashworth of the UCB Department of Plant Pathology. 

UCB-1 features superior disease resistance, cold tolerance, and tree vigor. One of the most popular rootstocks for new pistachio plantings. UCB-1 is usually planted in spring and field budded 3-4 months later or planted in summer or fall and field budded the following spring.

Pistachio trees are dioecious (meaning either male or female), and males are needed to pollinize female trees that produce nuts. The trees are best grown in semi-arid desert conditions where long, hot summers with temps 100F or above are the rule and winters are cool but not freezing. Needs 1000 chill hours at 45F or below, but not below 32F. Trees create vigorous taproot and should not be grown in pots after year 3. Sandy loam is optimal soil type. Expect production to begin 5-7 years after grafting.

USDA Zone: 7-11

Grow Height:  25′- 30′ (Standard)

Sun: Full Sun and High Heat

Soil ph: Neutral to Slightly Alkaline

Ripening Time: October

Pollination: Needs a Pollinizer