How to Plant, Grow, and Care for Lemon Cypress Trees
Looking for a stunning and versatile addition to your garden or houseplant jungle? Lemon cypress offers just that with year-round interest, a delicious lemon fragrance, a tidy habit, and relatively easy care requirements. Gardening expert Katherine Rowe walks us through guidelines on how to plant, grow, and care for lemon cypress all year.
Contents
Lemon cypress is a popular plant during the holidays, where we find it in decorative containers ready to gift and to use as tabletop decorations. Hold onto that tree beyond the holiday season – it makes a beautiful houseplant year-round!
It’s also a valuable landscape tree, adding a burst of color and fine texture against darker foliage as a specimen in the garden bed or among natural landscape elements like rocks.
The narrow, upright habit suits it for various garden and household locations. Employ it as a hedge, garden specimen, topiary, bonsai, or container feature. This plant lends outstanding ornamental value to its interior or exterior garden location.
Overview
Plant Type
Tree
Family
Cupressaceae
Genus
Hesperocyparis
Species
macrocarpa
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Native Area
California
Exposure
Full to part sun
Height
16 feet
Watering Requirements
Low
|
Pests & Diseases
Borers, aphids, armillaria, root rot
Maintenance
Low
Soil Type
Sandy, well-drained
Hardiness Zone
7-10
|
What Is Lemon Cypress?
Lemon cypress is an aromatic beauty that emits a fresh, lemony-citrus scent when brushing or crushing foliage. Most notable for its vibrant yellow-green color and pyramidal form, it is a cultivar of Monterey cypress.
Monterey cypress grows much larger, reaching 80’ tall, with a broad, windswept habit and dark green needles.
Characteristics
This striking columnar evergreen tree has a bold color and a fine texture. The needled foliage is chartreuse-yellow, especially in summer. Outdoors in cool weather it may take on an orange tinge, flushing yellow again as temperatures warm.
With its needled and aromatic foliage, lemon cypress is resistant to damage by deer and rabbits.
This is a dwarf tree that reaches 6-12 feet in the landscape and less in a container. ‘Goldcrest Wilma’ is perfect for containers at a maximum height of three feet.
Native Area
This tree is native to the Central Coast of California. Its parent plant, the Monterey cypress, occurs naturally in two groves localized to Monterey Bay. The Monterey cypress is nearly extinct in the wild but is widely cultivated as a landscape specimen.
The lemon cypress is of garden origin and has become popular in the United States, Europe, New Zealand, and Australia as a vibrant landscape tree.
It prefers mild climates with cool summers and wet winters. California’s Central Coast experiences a Mediterranean climate with arid, warm seasons and moderate cool seasons. Sandy soils and coastal breezes are the norm in its native climate.
Planting
While hardy in USDA zones 7-10, it is also a viable houseplant. In colder climates, grow in a pot to bring indoors in the winter. The dwarf nature makes it ideal for container culture, where it can live in a suitable container for three to four years before transplanting.
Transplanting
You can transplant the trees from their container to the in-ground garden in fall and spring. Early spring is ideal when the plant can adapt to its new environment without extreme temperatures during the growing season.
If moving to a larger container, opt for one that’s at least one inch larger in diameter than the existing pot. Give roots a little trim to allow more space for growth in the new pot and to keep the plant suited to its container-growing culture. Dwarf varieties can live for years in pots without outgrowing them.
Growing from Seed
Lemon cypress is a garden cultivar, and while it produces small, roundish uniform cones, seeds won’t produce the same plant as the parent. Essentially, seeds aren’t true to form as they would be in the native Monterey cypress. It’s best to propagate from cuttings.
How to Grow
The punchy, lemony-green color brings joy to the outdoor and indoor garden, and their carefree nature makes them a joy to grow. In their hardiness zones, they are easy-care and drought-tolerant trees once established.
In containers, they require much the same treatment as other potted plants – lots of light, good air circulation, and consistently moist, well-drained soils.
Light
This dwarf tree prefers direct sunlight for at least 4-6 hours. In the garden, plant in full to partial sun. They can benefit from afternoon sun protection in hot climates, where they may scorch.
As houseplants, place them where they get morning sun and bright light throughout the day. Again, avoid direct afternoon rays in an interior spot.
Water
While they are relatively easy care plants, they need water to get established in their first growing season. In the landscape, water regularly to achieve moist, but not soggy, soil. Plant in a location where soils are well-draining, as they don’t tolerate standing water.
In a container, water weekly (or as needed before the soil dries). Err on the dry side rather than overwatering, as wet soil can lead to root rot. They prefer evenly moist soil in a well-draining container.
Soil
The natural environment is sandy, rocky, and dry, with generally poor soils. These tough plants can withstand arid conditions and aren’t picky about soil pH. Nutrient-rich soils can lead to rapid growth, where the upper plant outpaces the root system.
The shallow root system can’t support the upright plant against wind and may cause the plant to topple over. It’s vital to give adequate time to establish a robust root system without external soil amendment.
In a container, a traditional potting mix works well. Opt for one with bark mix to ensure good drainage. Here, we can worry less about a landscape plant growing faster than the roots (although the roots are just as important!). If potting soil is very dense, consider mixing in a small amount of sand or native dirt, remembering that these lead to soil drying out more quickly in a container.
Temperature and Humidity
The ideal environment mimics coastal Mediterranean climates with cool, wet winters, dry summers, and ocean breezes. Ideal summer temperatures are below 80 degrees. In winter, below-freezing temperatures can damage or kill the plant. They benefit from winter protection, especially against winds, even where they are hardy.
Bringing these ideal natural conditions indoors can be challenging, but the proper placement ensures success. Place your plant away from air conditioning and heating vents to avoid drying drafts. Protect it from the afternoon sun to prevent scorching the foliage. Five to six hours of bright, indirect sun (or morning sun only) is best.
To increase humidity indoors, use a tray with water and pebbles at the pot’s base or mist as needed. This may be most useful in winter when heat and fireplaces can have a drying effect.
Fertilizing
Because this species performs best in poor soils, minimal (if any) fertilizing is needed, both in the landscape and in a container. If you’re noticing the plant isn’t flushing out of its winter form quickly, or if it’s been in the same container for some time and the soil needs a boost, it’s best to fertilize in early spring.
Maintenance
The naturally tidy form means it requires little pruning. It retains a narrow, pyramidal growth habit throughout its life. Prune any “stray” stems or branches or trim if using the plant as a hedge, bonsai, or topiary in early spring.
You may notice a little brown on the tips where cut; this is normal, and new growth will flush out bright yellow-green.
Propagation
You’ll see these readily available at nurseries in their hardiness zones. Outside these zones, look for them near the holiday season. For the ambitious gardener, consider taking cuttings from healthy stems to propagate more plants.
Cuttings
This is a semi-hardwood plant that is best propagated through cuttings. With a few steps and early monitoring, cuttings can produce new plants.
Here’s how best to take cuttings:
- Cut a four-to-six-inch piece of stem from a healthy branch. Cut the stem at a 45-degree angle to ensure more water and rooting hormone coverage.
- Remove the foliage from the bottom ⅔ of the cutting. Keep cuttings moist until ready to pot.
- Moisten the cutting and dip the lower stem in rooting hormone, coating generously. Tap off any excess rooting powder.
- Plant the cutting in at least two inches of moist, well-draining potting mix.
- Create a mini greenhouse environment by covering the pot with a plastic bag, closing with a twist tie, or using sticks to hold the bag away from the fresh stem.
- Place the pot in a bright, warm location, avoiding direct sunlight (which can make the environment too hot).
- Water as needed, keeping the soil evenly moist. Lift the plastic daily to allow air circulation, and mist the cutting if dry.
- The cutting is ready to be repotted when it gives resistance against a gentle tug. This means roots have taken hold.
- Plant the cutting in a pot, keeping it indoors in a bright spot or moving outside if conditions are mild.
Popular Varieties
Varieties of this plant come in a wide range of sizes. Both ‘Goldcrest’ and ‘Wilma Goldcrest’ are well-suited to the garden or the container, and both dwarf varieties do particularly well in pots. ‘Goldcrest’ tends to be slower-growing with denser branching than the popular dwarf selection ‘Wilma Goldcrest.’
Hesperocyparis macrocarpa ‘Wilma Goldcrest’
This variety is a winning hybrid between the Monterey cypress and the dwarf selection ‘Goldcrest.’ ‘Wilma Goldcrest’ is fast-growing with a more open branching habit than ‘Goldcrest.’ A mature ‘Wilma Goldcrest’ can reach six feet tall instead of the 12-foot tall ‘Goldcrest.’
Common Problems
This ornamental tree can be susceptible to damage in cold and hot extremes. Dieback can occur in these conditions and with prolonged dry soil unless established in the landscape. It is also prone to certain pests that can be treated and diseases that are more demanding to control.
Pests
Borers and cypress aphids can pose problems for this plant. Borers live among the roots and become bark beetles. The best control is prevention through cultural practices. Keep soil evenly moist to keep plants vigorous.
Fluctuation between periods of drought and overwatering can stress the plant and increase susceptibility to borers. If borers are present, remove the plant and soil to keep them from spreading elsewhere in the garden.
When growing it outdoors, spray the plant with water occasionally during warm months when pests are most active to deter and knock insects off the stems. A simple horticultural soap can rid the plant of aphids if infestation occurs.
Diseases
Armillaria, Phytophthora, Botrytis, and Coryneum canker are common diseases. Most of these are caused (or added to) by irregularities in soil moisture and air circulation that can lead to a less vigorous plant.
Armillaria
Armillaria, or honey fungus, attacks and kills the roots of many perennial and woody plants. It often appears as a white powdery substance at the ground level of the bark. Sometimes, clusters of honey-brown mushrooms appear above the soil.
Armillaria can cause sudden death of the plant. If this fungus is present, excavating and removing the plant and soil is the only control. Remove the infected area to keep it from spreading to other garden areas.
Phytophthora
Phytophthora is a fungal root rot that causes a slow decline of the plant, impacting feeder roots so they can’t uptake water and nutrients.
The best control is proper cultural management, especially in not overwatering the roots. A fungicide can be applied if the plant shows signs of stress like leaf drop and brown or decaying feeder roots.
Botrytis
Botrytis root rot is a fungal disease, especially prevalent in high-humidity conditions with limited air circulation. Brown spots and “fluffy mold” are indicators of botrytis.
To treat botrytis, trim the infected areas and place the plant outdoors with good air ventilation. Plants can be sprayed with a fungicide as a last resort. Take care not to overwater or overfertilize, which weakens the plant.
Coryneum Canker
Coryneum canker, or cypress canker, is a fungus characterized by lesions on bark and stems and branch dieback. This fungus moves into already-existing wounds on the plant, especially during periods of prolonged fog or moisture.
Again, the best control is preventative – a plant well-adapted to its environment is less susceptible. If cypress canker occurs, remove affected branches to prevent spread to the whole plant.
Frequently Asked Questions
Can I keep my lemon cypress beyond the holiday season?
Yes! Keep them year-round as houseplants and as garden specimens. Make sure to offer plenty of light, evenly moist soil, and winter protection. The bright foliage makes a striking addition to the landscape or interiorscape in any season.
How big do lemon cypress get?
These are dwarf cultivars of the larger Monterey cypress. ‘Goldcrest’ can grow to 12 feet tall and 6 feet wide in the landscape and much smaller in a container. ‘Wilma Goldcrest’ is even more dwarfed at a maximum of six feet tall in the landscape and as small as three feet in a container.
How do you overwinter lemon cypress?
In USDA hardiness zones 7-10, it can be planted in the landscape. Offer protection from winter winds, even where hardy. In colder climates, keep your plant in a container and move it indoors during winter. Keep soil evenly moist in a well-drained pot, and keep away from heat vents and fireplaces to avoid excessive drying.
Final Thoughts
With its striking color, form, and lemony fragrance, it’s no wonder lemon cypress has achieved The Royal Horticultural Society’s Award of Garden Merit.
Use this pretty tree as a landscape specimen, hedge, topiary, bonsai, or container planting. Pair it with winter hardy annuals like violas and pansies for high contrast during cooler seasons. In warmer months, the chartreuse color and fine texture are beautiful against deep purple foliage plants like heuchera and bladed leaves of ornamental grasses. Its cheery and bright needles add an unparalleled punch to the garden.