Perform a soil test in the desired planting location. Soil kits are available in garden centers, plant nurseries and from online vendors. Irish Eyes cypress prefers to grow in soil with a pH between 5.5 and 6.5. If your soil does not meet these requirements, amending is necessary to ensure the healthy growth of the tree.
Break up the soil to an 18-inch depth with a pitchfork and amend if necessary. A pH that is lower than 5.5 will require the addition of lime before planting Irish Eyes. If your soil pH is above 6.5, peat moss will lower it to acceptable levels. Add the amendment to the soil according to the manufacturer's instructions listed on the label.
Dig the planting hole for the Irish Eyes cypress three times the width of the root-ball. Make the hole just as deep as the root-ball is tall. Remove the cypress from its container by tipping it on its side and sliding it out -- leave the roots and attached dirt intact.
Stand the tree upright and set in the center of the hole. Check that the root-flare (union of trunk and roots) is higher than the soil line. Take a few steps back if necessary to get a good view of the cypress. If the root-flare is below the soil line, the addition of soil to the bottom of the hole will raise it up. When the Irish Eyes cypress is in position, backfill the hole halfway.
Soak the hole with water from a garden hose. Continue backfilling when the water recedes. Use your foot to tamp the soil down after backfilling to remove trapped air around the roots of the cypress tree.
Support the Irish Eyes cypress by hammering in a 4-foot metal stake. Attach the trunk of the tree to the support using strips of cotton cloth or cut pieces of a garden hose secured with wire. Staking will prevent the young cypress from toppling over in heavy winds and soaking rains.
Keep the Irish Eyes cypress well watered with twice-a-week soakings. Maintain moist soil to a depth of 1 inch at all times. Supplemental watering will be necessary for the first year of growth. Once the cypress establishes its roots in the soil, supplemental watering will only be necessary during droughts.
Begin fertilizing the cypress tree after the first growing season. A dose of 18-8-8 fertilizer in the spring will encourage new growth and healthy development. Apply the fertilizer according to the label directions.