One of the fastest-growing privacy trees you can plant — up to 3 feet per year. Here's how to give your Thuja Green Giant the best start.
Thuja Green Giants need full sun (6+ hours daily) and well-drained soil. They're flexible on soil type — clay, loam, or sandy soil all work. Space them 5–6 feet apart for a privacy screen, or 10+ feet apart for a standalone specimen.
Tip: Avoid planting directly under powerlines. Green Giants can reach 60 feet at maturity.
Dig a hole 2–3 times wider than the root ball, and exactly as deep. Wider is better — it loosens the surrounding soil so roots can spread easily. Resist the urge to dig deeper than the root ball, though. Planting too deep is the most common mistake, and it causes trunk rot.
Place the tree in the hole. The root flare should sit right at ground level. This is the single most important step. Trees planted too deep develop root rot; too shallow and the roots dry out. When in doubt, slightly high is better than too deep.
Tip: If you can see the root flare above the soil, you're in good shape. If you can't, the tree is too deep — add soil underneath and re-check.
Fill the hole with the original soil — no amendments needed for Green Giants. Add soil back in layers, about 4–6 inches at a time. After each layer, press down firmly with the flat of your foot or the end of the shovel handle. This pushes out air pockets that would otherwise dry out roots. Stop filling when the soil reaches the top of the root ball.
Tip: Press your thumb into the backfilled soil. If it sinks more than half an inch, tamp again. If it doesn't budge at all, you've overdone it — loosen the top inch with your fingers.
Give the tree a long, slow soak immediately — 15–20 minutes at a trickle. This settles the soil around the roots and eliminates hidden air pockets. In the first growing season, water deeply 2–3 times per week.
Spread 2–3 inches of mulch in a circle, extending 2–3 feet from the trunk. Keep the mulch a few inches away from the trunk itself — piling it against the bark invites rot and pests. Mulch retains moisture, moderates soil temperature, and suppresses weeds.
In ideal conditions, Thuja Green Giants grow 3–5 feet per year once established. During the first year, expect slower growth as the tree focuses on root development. By year 2–3, you should see significant height gains.
Thuja Green Giants can tolerate partial shade (4–6 hours of sun), but they'll grow more slowly and may develop a thinner shape. For a dense privacy screen, full sun (6+ hours) is strongly recommended.
Fall (September–November) is the ideal planting window because cool temperatures and natural rainfall help roots establish before summer heat. Spring (March–May) is also a good time. Avoid planting in the heat of summer or when the ground is frozen.
Plant at least 4–5 feet from fences and property lines. Thuja Green Giants can spread 8–12 feet wide at maturity. Check your local setback rules — some municipalities require plantings to be a certain distance from property boundaries.
Not at planting time — fresh fertilizer can burn new roots. After the first growing season, you can apply a balanced slow-release fertilizer (like 10-10-10) in early spring.
Some browning of interior foliage is normal, especially in fall — it's the tree shedding older needles. However, browning at branch tips can indicate drought stress, root rot (from planting too deep), or pest issues. Check your watering schedule and make sure the root flare is at soil level.