Arborvitae roots grow best when planted in early fall or late spring to avoid extreme temperatures. Knowing when is best time to plant arborvitae can mean the difference between a thriving hedge and a struggling shrub. Many gardeners rush to plant in summer, only to watch their trees wilt under heat stress.
Getting the timing right gives your arborvitae a strong start. The roots need cool soil and consistent moisture to establish before winter or summer arrives. This article walks you through the exact seasons, signs, and steps for planting success.
When Is Best Time To Plant Arborvitae
The best time is early fall, about 6 to 8 weeks before the first hard frost. This window lets roots grow in warm soil while the air stays cool. Late spring, after the last frost, is the second-best option.
Fall planting reduces transplant shock. The soil is still warm from summer, encouraging root development. Cooler air temperatures mean less water loss from leaves. Your arborvitae can focus energy on root growth instead of fighting heat.
Spring planting works well too, but you must wait until the ground thaws and dries enough to work. Planting too early in wet soil can cause root rot. Aim for a period when night temperatures stay above 40°F.
Why Fall Beats Spring For Arborvitae
Fall gives roots a head start. They grow until the soil freezes, which might be weeks after planting. By spring, the root system is already established. The tree can handle summer heat better.
Spring-planted arborvitae face a race against time. They need to grow roots quickly before summer stress hits. If you plant in late spring, you must water consistently. Miss a few days, and the tree may suffer.
Another advantage of fall: fewer pests and diseases. Many insects are less active in cooler weather. Fungal issues also decrease as humidity drops. Your tree faces less pressure during establishment.
Regional Variations In Planting Time
Your local climate changes the ideal window. In northern zones (3-5), early fall means September. The ground freezes sooner, so plant by mid-September. Spring planting should happen in April or early May.
In moderate zones (6-7), you have more flexibility. Fall planting can stretch into October. Spring planting works from March to April. Avoid planting during hot, dry spells in summer.
In southern zones (8-9), fall is still best, but you can plant through November. Winter is mild, so roots keep growing. Spring planting should happen in February or March before heat arrives. Summer planting is risky unless you provide shade and extra water.
Signs Your Arborvitae Is Ready To Plant
Look at the soil first. It should be moist but not soggy. Squeeze a handful of dirt; if water drips out, wait a few days. The soil should crumble easily.
Check the weather forecast. Avoid planting right before a heavy rain or a heatwave. Ideal conditions are overcast days with mild temperatures. Windy days can dry out roots quickly.
Inspect the root ball. If it’s pot-bound with roots circling the container, loosen them gently. If the roots are white and healthy, the tree is ready. Brown or mushy roots indicate problems.
Soil Temperature Matters
Use a soil thermometer. For fall planting, soil should be between 50°F and 65°F. For spring, wait until soil reaches at least 45°F. Cold soil slows root growth and increases rot risk.
You can test soil temperature by inserting the thermometer 4 inches deep. Take readings at different times of day. Morning temperatures are coolest; afternoon readings are more accurate for planting.
If soil is too cold, delay planting. Your arborvitae will survive in its pot for a few weeks. Keep it watered and in partial shade until conditions improve.
Step-By-Step Planting Guide
Follow these steps for the best results. Timing is just one part; proper technique ensures success.
- Choose a location with full sun to partial shade. Arborvitae need at least 6 hours of sunlight daily.
- Dig a hole twice as wide as the root ball but no deeper. The top of the root ball should sit level with the ground.
- Remove the tree from its container. Gently loosen any circling roots with your fingers or a knife.
- Place the tree in the hole. Check that it’s straight and at the right depth.
- Backfill with the original soil. Do not add compost or fertilizer at planting time.
- Water thoroughly. Let the water soak in, then water again. The soil should be moist to the bottom of the hole.
- Add 2-3 inches of mulch around the base. Keep mulch away from the trunk to prevent rot.
- Stake the tree only if it’s in a windy spot. Remove stakes after one growing season.
Watering After Planting
Water deeply once a week for the first month. In fall, you may need less if rain is frequent. In spring, watch for dry spells and water more often.
Check soil moisture by sticking your finger 2 inches into the ground. If it feels dry, water. If it’s wet, wait. Overwatering is as harmful as underwatering.
Reduce watering as temperatures drop in fall. Once the ground freezes, stop watering until spring. For spring planting, continue weekly watering through summer.
Common Mistakes To Avoid
Planting too deep is a frequent error. The root ball should be slightly above ground level, not below. Buried trunks rot easily.
Planting in summer heat stresses the tree. Leaves may turn brown and drop. If you must plant in summer, do it in the evening and water daily for two weeks.
Ignoring soil drainage is another mistake. Arborvitae hate wet feet. If your soil is clay, plant in a raised bed or amend with sand and organic matter.
Using too much fertilizer at planting time burns roots. Wait until the next growing season to feed. A slow-release fertilizer in spring works well.
What If You Miss The Ideal Window?
If you miss fall, wait until spring. Do not plant in winter when the ground is frozen. The roots cannot grow, and the tree may die.
If you miss spring, plant in early summer with extra care. Provide shade for the first week. Water every other day until the tree shows new growth.
Container-grown arborvitae are more forgiving. They can be planted any time the ground is workable, but avoid extreme heat or cold. Balled-and-burlapped trees need the ideal window for best survival.
How Weather Affects Arborvitae Roots
Roots grow best in cool, moist soil. Temperatures above 80°F slow root development. Below 40°F, roots go dormant. The sweet spot is 50°F to 65°F.
Hot weather causes roots to dry out quickly. Leaves transpire more water than roots can absorb. This leads to wilting and browning. Planting in cool weather avoids this stress.
Frost heaving is a risk in cold climates. When soil freezes and thaws, it can push young trees out of the ground. Mulch helps insulate the soil and reduce heaving.
Mulching For Temperature Control
Apply mulch after planting. It keeps soil temperature stable and retains moisture. Use wood chips, bark, or straw.
Spread mulch in a 3-foot circle around the tree. Make it 2-3 inches deep. Do not pile mulch against the trunk; leave a 2-inch gap.
In fall, mulch protects roots from freezing. In spring, it keeps soil cool as air warms. Refresh mulch each year to maintain its benefits.
Choosing The Right Arborvitae Variety
Different varieties have different needs. ‘Emerald Green’ is popular for hedges and grows well in zones 3-7. ‘Green Giant’ is faster-growing and tolerates heat better.
For small spaces, ‘Little Giant’ or ‘Golden Globe’ work well. They stay compact and need less pruning. Check the mature size before planting.
Native varieties like ‘American Arborvitae’ are hardy and disease-resistant. They adapt to local conditions better than exotic types. Ask your local nursery for recommendations.
Where To Buy Arborvitae
Buy from reputable nurseries. Look for trees with green, healthy foliage and no brown tips. Avoid trees with roots growing out of drainage holes.
Online retailers offer convenience but check reviews. Some ship bare-root trees, which need immediate planting. Container trees are easier for beginners.
Local garden centers often have varieties suited to your area. They can also advise on planting times specific to your region. Support local businesses when possible.
Long-Term Care After Planting
Water deeply during dry spells for the first two years. Established arborvitae are drought-tolerant but still need occasional watering in extreme heat.
Prune in early spring before new growth starts. Remove dead or damaged branches. Shape hedges lightly; avoid cutting into old wood.
Fertilize once a year in spring with a balanced fertilizer. Follow package directions. Over-fertilizing causes weak growth and pest problems.
Watch for pests like bagworms and spider mites. Treat with insecticidal soap if needed. Healthy trees resist pests better than stressed ones.
Winter Protection For Young Trees
In cold climates, wrap young arborvitae in burlap. This prevents windburn and snow damage. Remove the wrap in spring when temperatures rise.
Water well before the ground freezes. Moist soil holds heat better than dry soil. This helps roots survive winter.
Shake heavy snow off branches to prevent breakage. Use a broom gently. Do not let snow accumulate for long periods.
Frequently Asked Questions
Can I plant arborvitae in summer?
Yes, but it’s risky. Plant in early morning or evening. Water daily for two weeks. Provide shade if temperatures exceed 85°F.
How long does it take for arborvitae roots to establish?
Roots establish in 6-12 months. Fall-planted trees have a head start. Spring-planted trees may take a full year to settle.
What happens if I plant arborvitae too late in fall?
Roots may not grow before frost. The tree can survive if mulched well, but growth will be slow in spring. Water until the ground freezes.
Should I soak the root ball before planting?
Yes, if the root ball is dry. Soak it in a bucket of water for 30 minutes. Do not soak for more than an hour; it can drown the roots.
Can I plant arborvitae in winter?
Only if the ground is not frozen. In mild climates, winter planting works. In cold areas, wait until spring. Frozen soil prevents root growth.
Final Tips For Success
Plan ahead. Check your local frost dates and soil temperature. Mark your calendar for the ideal planting window.
Prepare the site before buying trees. Remove weeds and amend soil if needed. Have mulch and tools ready.
Water consistently but not excessively. Arborvitae prefer deep, infrequent watering over shallow daily sprinkles.
Be patient. Arborvitae grow slowly at first. Once established, they can add 1-2 feet per year. Give them time to thrive.
Remember the key point: when is best time to plant arborvitae? Early fall or late spring. Avoid extremes. Your trees will reward you with years of green beauty.
With proper timing and care, your arborvitae hedge will become a lush, living fence. It provides privacy, wind protection, and year-round color. Start planning now for a successful planting.