Newly Planted Arborvitae Turning Brown — What’s Happening and How to Fix It
Seeing your newly planted arborvitae turn brown is upsetting. You bought those evergreen columns to create privacy, structure, and year-round green, and suddenly they look sickly. I’ve been through this myself more than once, so here’s a practical, gardener-to-gardener guide to diagnosing why arborvitae turn brown after planting and what you can do to save them.
What “turning brown” usually looks like
New browning can appear as tip dieback, patchy brown sections, or entire stems fading to brown. Sometimes only the inside foliage browns while the outer tips remain green. How the browning develops gives big clues about the cause.
Common Causes of Browning in Newly Planted Arborvitae
Transplant shock
When roots are disturbed, the plant temporarily can’t supply enough water to leaves. Browning often starts at the tips and progresses inward. This is common in the first few weeks to months after planting.
Water stress — too little or too much
Newly planted trees need consistent moisture while roots establish. Underwatering causes crispy brown tips. Overwatering or poor drainage causes root rot and yellowing that turns brown as tissue dies.
Root damage or planting depth errors
Roots cut too short, planted too deep, or with the root flare buried will struggle. If roots aren’t in good contact with native soil, they can’t take up moisture.
Pests and diseases
Bagworms, spider mites, and fungal pathogens such as Phytophthora can cause browning. Pests often leave telltale signs like webbing, bags hanging from branches, or sticky residue.
Winter burn and environmental stress
Evergreen browning can follow winter exposure to sun, wind, or salt. Newly planted arborvitae haven’t built a deep root system to replenish moisture lost from foliage.
Soil salinity or herbicide drift
Salt from de-icing roads or drifting herbicides can scorch foliage, producing irregular brown patches. This is often near sidewalks, driveways, or lawns treated with weed control.
How to Diagnose the Problem
Quick, systematic checks will help you decide whether the plant can be saved and what action to take next.
- Inspect the foliage closely for insects, webbing, or sticky sap.
- Check soil moisture 3–6 inches down. Is it bone dry, damp, or soggy?
- Gently scratch a small section of bark — green under the bark means live tissue, brown/gray means dead.
- Examine roots by carefully lifting one side of the root ball if possible. Healthy roots are white and firm; rotted roots are brown/black and mushy.
- Look for planting depth problems — the root flare should be at soil level, not buried.
Immediate Steps to Take
If the soil is dry
Water deeply right away. A newly planted arborvitae benefits from a slow soak that wets the root ball and surrounding soil to a foot or more deep. Repeat weekly (more in hot weather) until established. I like to use a soaker hose around the base for an hour or two.
If the soil is waterlogged
Stop watering and improve drainage. If the root ball sits in standing water, you may need to lift and replant on slightly higher ground with amended soil to improve drainage. Fungicide drenches can help with Phytophthora, but only after correcting drainage.
If pests are present
Remove bags or insect masses by hand early in the season. For heavy infestations, use an appropriate insecticide or insecticidal soap. For spider mites, a strong spray of water can knock them off and reduce damage.
If only tips are brown
Prune back dead tips to healthy green wood. Pruning helps redirect the plant’s energy to new growth rather than trying to maintain dead tissue.
From my own experience: I lost a few tips the first summer after planting a row of Thuja when we had a heatwave. After switching to deep weekly watering and mulching, most of them greened up in the following spring.
Long-Term Fixes and Prevention
Keep these practices in mind when planting and caring for new arborvitae.
- Plant at the proper depth — root flare at soil level. Don’t bury the trunk.
- Improve soil drainage if you have heavy clay. Mix compost or sharp sand into backfill where necessary.
- Mulch 2–3 inches around the base, keeping mulch a few inches from the trunk to prevent rot.
- Water deeply and infrequently rather than shallow daily watering. New plants need regular moisture during the first two growing seasons.
- Avoid fertilizing heavily the first year; root systems are establishing and too much nitrogen stresses them.
- Protect from winter wind and salt where necessary — use a burlap windscreen or anti-desiccant spray late fall for exposed sites.
- Choose cultivars suited to your hardiness zone and salt exposure. Some varieties tolerate heat and salt better than others.
When to Give Up and Replace
Be patient — many newly planted arborvitae recover in a season or two. However, replace if:
- More than half the canopy is dead and there’s no green tissue under the bark.
- Root rot has destroyed the majority of roots (mushy, black roots).
- Pest or disease keeps returning despite treatment and the plant shows progressive decline.
Final Checklist for Troubleshooting Browning Arborvitae
- Identify symptoms: tip browning vs whole-branch browning vs root issues.
- Check soil moisture and drainage.
- Inspect for pests and disease signs.
- Correct planting depth and root health.
- Adjust watering, mulch, and protection strategy.
- Prune dead tissue and monitor over the next season.
Closing thoughts
Newly planted arborvitae turning brown is usually a solvable problem if you act quickly and diagnose the cause. Most of the time it’s a simple water or planting issue, and with deep watering, proper mulching, and a little patience you can often nurse them back to good health. If you’re unsure, take clear photos and contact your local extension office — they can identify diseases or pests specific to your area. I’ve lost a few over the years, but I’ve learned that careful planting and consistent early care make the difference between a permanent loss and a thriving privacy screen.
