How to Grow Pistachio Kerman

Young tree with developing scaffold branches and root system. Foliage is compound, feathery, and light green.

Provide consistent deep watering 2-3 times weekly. Apply 4-6 inches of mulch, keeping 6 inches from trunk. Stake for wind protection. Avoid fertilizer in first year; apply balanced fertilizer lightly in years 2-3.

Tree develops strong branch structure and canopy. Compound pinnate leaves emerge in spring; tree remains leafless in winter. Height and spread increase significantly.

Water deeply during dry periods. Prune to maintain open vase shape with 3-4 main scaffold branches. Remove crossing or diseased branches. Apply boron annually as foliar spray or soil drench (check soil levels first).

Inconspicuous male and female flowers appear on separate trees. Flowers are small, greenish, and borne in panicles. Heavy pollen production from male flowers; female flowers are discrete.

Kerman is primarily female and requires a male pollinizer tree (typically 'Peters' or 'Golden Hills'). One male tree can pollinate 8-10 females. Ensure good air circulation for pollen dispersal. Avoid heavy nitrogen fertilization which delays flowering.

After pollination, small green drupes form and expand. Nuts develop inside. Husk splits and turns reddish-brown in late summer. Shell splits naturally when mature, revealing cream-colored kernel.

Maintain consistent moisture through hull-split stage (mid-August to September). Apply post-bloom potassium and boron if soil tests warrant. Monitor for split-pit defect if temperatures fluctuate dramatically. Thin if excessive set to encourage larger nut size.

Nuts mature and drop naturally starting in late September through October. Husked, dried kernels are ready for consumption or storage.

Harvest by shaking tree or allowing nuts to fall naturally; collect promptly to prevent sprouting or pest damage. Dry nuts to 5-7% moisture content before storage. Prune lightly after harvest. Prepare for alternate-bearing cycle by pruning if necessary.