Growing a tree from seed is a project for the long haul. Sow an Arizona cypress (Cupressus arizonica) seed when your child is born, and it may still not have reached its mature height by the time he graduates high school. Patient gardeners in areas of U.S. Department of Agriculture plant hardiness zones 7 through 9 with hot, dry summers might want to try raising the fragrant evergreen from seed for a year-round windbreak and source of shade that -- eventually -- reaches a height of 30 to 50 feet tall and a width of 15 to 35 feet.
Pick ripe Arizona cypress seed cones when they are dull gray to brown, or purplish. Seeds drop from the cones when they mature, so harvest the clusters of rounded seed cones as soon as the color darkens. Each cone may have 90 to 120 seeds, though only about a third of them may germinate, so collect the number of cones you need for your seed-starting project.
Lay the cones out in a sunny, protected place for about two weeks until they open and shed their seed. Arizona cypress seeds are oblong and tiny -- about 1/12 inch long and less than half that in width -- and should be medium to dark brown. Discard pods where the seed doesn't shake right out -- those seeds are often immature or damaged by insects.
Place the dry seed in a zipper top plastic bag, and store it in a cool, dry place until 30 days before spring temperatures are expected to be at least 68 degrees Fahrenheit .
Add a small amount of damp peat moss to the bag with the seeds, reseal it and place the bag in the refrigerator for 30 days.
Create a raised bed that is about 3 feet wide and 6 feet long to serve as a nursery seed bed. Site the bed in an area that is easy to water and gets dappled sun. Create a seed bed that is two-thirds native soil and one-third compost or peat moss with a handful or two of bone meal scattered across the surface and worked in. Break up any clumps, and rake the top of the bed smooth.
Scatter your chilled seeds across the top of the nursery seed bed, and cover with 1/4 inch of soil.
Keep the soil consistently moist, and the seeds should germinate in 20 to 30 days.
Items you will need
- Paper towels
- Plastic zipper-top bags
- Peat moss
- Bone meal
- Thin to the strongest seedlings, digging and moving them at least 12 inches apart as necessary. You can dig up your Arizona cypress and place them in full sun in soil with good drainage in late winter to early spring the next year.
- Arizona cypress is considered safe for planting around children and animals, but can cause problems if anyone in your family has tree pollen allergies.
- University of Florida IFAS Extension: Cupressus arizonica var. arizonica: Arizona Cypress
- Shoot: Cupressus Arizonica
- Woody Plant Seed Manual, Part 2; Franklin T. Bonner
- Plants for a Future: Cupressus Arizonica - Greene
- U.S. Forest Service: Creating a School Yard Tree Nursery
- Hawaiian Ecosystems at Risk Project: Cupressus Arizonica