How to Grow and Care for Lemon Cypress Trees

You might recognize the lemon cypress as the potted evergreen that seems to show up in every big box retail store before Christmas. However, this narrow, columnar evergreen tree is more than a lemon-scented holiday plant for indoors. It is a versatile needled conifer that can be used as a hedge, specimen, bonsai, or kept in a container on a patio.

Also commonly referred to as the Goldcrest Monterey Cypress, Cupressus macrocarpa ‘Goldcrest’ (also known as Hesperocyparis macrocarpa) is a Monterey cypress cultivar with upward-growing branches. The unique yellow-green color of the lemon cypress can play off darker greens of other conifers, while texture can be experimented with by placing the shrub next to boulders and fencing.

Lemon Cypress Care

One of the great things about C. macrocarpa ‘Goldcrest’ is that it is an easy plant to care for.

• Provide full sun to partial shade.
• Do not enrich the soil.
• Water a new plant weekly until established.
• The only maintenance required will be some pruning if you want to keep its size down, or yearly trimming if using it as a hedge.

Light

The tree requires a good amount of light. Outdoors, it should be planted in full sun to partial shade. Indoors, it needs five to six hours of indirect sunlight or morning sun. The hot direct afternoon sun in a west-facing window can be detrimental to the vibrant foliage.

Soil

Planting this tree in soil that is too rich invites trouble. The lemon cypress is adapted to grow in poor, sandy, well-draining soils that are low in organics and not very fertile. This infertile soil allows the slow-growing tree to pace its development to match its height with its roots, helping to ensure that winds do not blow the thin and narrow plant over.

Water

As an outdoor shrub or tree, once established, the lemon cypress needs little supplemental watering. To allow the plant to establish itself, water once a week during the first season.

If kept as a houseplant, give it a thorough deep watering weekly, ensuring the soil is never too dry.

Temperature and Humidity

A lemon cypress prefers cool, moist climates. Temperatures above 80 degrees F in dry areas will tax the plant, while temperatures lower than 20 degrees F may cause tree damage or death.

When used as a houseplant, the lemon cypress needs to be kept in a place that has sufficient humidity.

Fertilizer

Fertilizing this shrub is not suggested. The lemon cypress is adapted to thrive in poor, infertile soil conditions. Rich soils will cause quick, uneven growth and could result in the tree being unstable. 

Types of Lemon Cypress

In addition to the straight species. Cupressus macrocarpa. a few cultivars of Monterey cypress have been bred:

• C. macrocarpa 'Goldcrest Wilma': a slow-growing dwarf cultivar, 6 to 8 ft. tall, and 1 to 2 ft. wide, with fragrant, golden yellow needles
• C. macrocarpa 'Golden Pillar': with golden yellow needles when grown a sunny location, and a mature size of 20 ft. tall and 4 ft. wide
• C. macrocarpa 'Citriodora': a slow-growing cultivar that can reach 15 to 30 ft. in height. New growth is bright yellow and turns deep green in the first year.

Pruning

The tree looks impressive in its natural, untrimmed, slow-growing upright shape. The only regular pruning maintenance required is when the lemon cypress is used as a hedge or as a bonsai or topiary. In these cases, it needs to be done carefully and in a timely fashion. This shrub, like most conifers, does not take well to hard pruning.

Propagating Lemon Cypress

The best time for propagating lemon cypress from cuttings is in the winter. Here's how it's done:

1. With a sharp knife, cut a piece of stem about 4 inches long.
2. Strip the foliage off the bottom part of the stem so the first 2 inches are bare. Moisten the cut end and dip it in rooting hormone. 
3. Have a pot filled with moist, well-draining potting mix ready. Using a pencil, poke a hole in the soil mix and insert the cutting in it.
4. Cover the pot with a plastic bag and use sticks to keep the plastic in place. Make sure the plastic does not touch the cutting. 
5. Place the pot in a warm location but away from direct sunlight. Water it as needed to keep it evenly moist.
6. When the cutting has developed a good root system—you'll know it's there when the stem does not move if you gently tug on it—it's time to remove the plastic bag and move the pot to a sunny location and let the sapling continue to grow in the pot, or transplant it outdoors.

How to Grow Lemon Cypress From Seeds

Most Monterey cypress are cultivars and propagating them from seed does not produce a plant with the same features as the parent, therefore, propagation from seed is not recommended.

Potting and Repotting Lemon Cypress

Excellent drainage is crucial for lemon cypress so make sure the pot you use has large drain holes. Terra-cotta pots are ideal because they let air get to the roots but the pots also dry out faster so adjust the watering frequency accordingly.

If keeping the lemon cypress in a container, it should be repotted once every three to four years. Move it to a larger pot at least one inch wider than the old pot and backfill with fresh potting mix. Prune the roots conservatively to keep growth in check while repotting.

Overwintering

Even when grown in a temperature range where it can be grown outdoors, cold winter winds burn the needles so the tree needs some protection. Below USDA zone 7, lemon cypress is best grown in a container and brought indoors during the winter. Keeping the tree moist during the winter is vital and will be most difficult when a heater is being run or windows are shut. Misting or a humidifier might be needed to help supplement the ambient room humidity.

Common Pests & Plant Diseases

Monterey cypress is prone to attacks by aphids, mealybugs, caterpillars, and scale insects. These usually don't affect the overall health of the tree and can be controlled with insecticidal soap.

A more serious problem is coryneum canker, a fungus that can kill the tree. To keep it under control, remove infected branches promptly and dispose of them in the trash.

Common Problems With Lemon Cypress

After pruning a potted lemon cyprus, you might notice that the tips of the pruned branches turn brown. That is part of the natural process and the brown spots should be disguised in due time by new bushy growth.