Your neighbor’s new second story looks straight into your backyard, and you want a privacy screen up before next summer, not in ten years. Fast-growing sounds like exactly what you need. It’s also exactly the phrase that gets people into trouble.
We get calls constantly about “fast growing privacy trees” in Boise, and almost as often, we get calls a few years later about the fast-growing trees someone already planted that are now falling apart, dying back, or turning into a maintenance headache. Fast growth and weak wood tend to travel together. This guide covers what actually holds up here, in our wind, our alkaline soil, and our dry summers, without setting you up for a redo in year eight.
Want a species recommendation specific to your yard, sun exposure, and how fast you actually need coverage? Get a free consultation before you commit to a full row of anything.
The Fast-Growing Tradeoff You Need to Understand First
Here’s the physics of it. A tree that adds 3 feet of height a year is putting that growth into new wood fast, and fast wood is generally less dense, less structurally sound wood. That’s not true of every fast grower, but it’s true of most of the classic “instant privacy” picks: Lombardy poplar, silver maple, Siberian elm, weeping willow. They deliver height quickly and then spend the next twenty years breaking apart in every windstorm, which in the Treasure Valley means multiple times a year.
The trees on this list were chosen because they balance a reasonable growth rate against wood strength, wind tolerance, and Boise’s alkaline, clay-heavy soil. None of them are instant. All of them are still standing, intact, in ten years, which is worth more than a head start you have to remove and replace.
Arborvitae: Popular, But Know the Limits First
Arborvitae (‘Green Giant’ and ‘Emerald Green’ especially) is probably the most requested privacy tree in the Treasure Valley, and it’s a reasonable choice with some real caveats.
What works: Dense, year-round screening, relatively fast growth (1 to 3 feet per year for ‘Green Giant’), and a classic, tidy look that most homeowners want for a fence-line screen. Regular trimming keeps a hedge like this dense at the base instead of thin and leggy.
What doesn’t: Arborvitae has shallow roots and can suffer in Boise’s wind, especially in exposed locations or during our stronger spring windstorms. It also struggles in heavier alkaline clay without good drainage, and it needs consistent irrigation through our dry summers or it browns out fast, sometimes permanently. We see a lot of arborvitae hedges with dead or thin patches from inconsistent watering or poor site prep, not from the tree itself being a bad choice.
Where it works best: a site with decent drainage, some wind protection (not directly exposed to prevailing gusts), and a reliable irrigation plan. Skip it on an exposed, unamended clay site with sprinkler-only watering.
Better Fast-Growing Privacy Trees for Wind and Alkaline Soil
Austrian pine handles wind, drought, and alkaline soil about as well as any evergreen we plant in the valley. It grows a bit slower than arborvitae, roughly 1 to 2 feet per year once established, but the wood and root structure are far more storm-resistant, and it doesn’t need the babying that arborvitae does. For a wind-exposed property, this is usually our first recommendation over arborvitae.
Hybrid poplar (not Lombardy) offers genuinely fast growth, 4 to 6 feet a year in good conditions, with noticeably better wood strength than the old Lombardy poplar or cottonwood. It’s still not a 50-year tree the way an oak is, but for a deciduous screen you want up fast, it’s a dramatically better bet than the poplar varieties that show up in older neighborhoods.
Hackberry, while not usually thought of as a “privacy tree,” makes an excellent fast, tough option for a looser, more naturalistic screen. It tolerates everything Boise throws at it (wind, drought, alkaline soil, neglect) and does it with strong wood and minimal maintenance. It’s deciduous, so it won’t give you winter privacy, but for a summer screen with structure you won’t be fixing in a decade, it’s hard to beat.
Colorado blue spruce grows more slowly than the above (1 to 2 feet per year), but it’s exceptionally wind-hardy, handles our clay reasonably well, and gives you a genuinely permanent, low-maintenance evergreen screen if you can be patient for the first several years.
Fast-Growing Privacy Trees to Avoid
We covered most of these in detail in our worst trees to plant in Boise guide, but specifically for privacy screening:
- Lombardy poplar: fast, narrow, and reliably dead or dying from canker within 10 to 15 years
- Silver maple: brittle wood that fails constantly in wind, plus invasive roots near any nearby fence or hardscape
- Weeping willow: needs far more water than a screen planting can reasonably get, and the roots go looking for your sewer line
- Siberian elm: fast and tough, but constant branch drop and self-seeding make it a long-term maintenance burden, not a low-effort screen
If you already have a row of these planted along your fence line, that’s not necessarily an emergency, but it’s worth an honest look before the next big windstorm decides the timeline for you.
Spacing: How Far Apart to Plant a Privacy Row
Spacing mistakes are almost as common as species mistakes. Plant too close and you get crowded, weak growth and disease pressure from poor air circulation. Plant too far apart and you wait years longer for a solid screen than you needed to.
| Species | Typical mature width | Recommended spacing for a solid screen |
|---|---|---|
| Arborvitae ‘Green Giant’ | 12-20 ft | 6-10 ft apart |
| Austrian pine | 20-40 ft | 15-20 ft apart |
| Hybrid poplar | 20-30 ft | 12-15 ft apart |
| Hackberry | 40-60 ft | 25-30 ft apart (looser screen) |
| Colorado blue spruce | 15-25 ft | 12-15 ft apart |
Also give real thought to the property line itself. Fast-growing trees planted too close to a fence or a neighbor’s yard create the exact disputes we cover in our guide to planting distance from a property line, and a privacy screen that annoys your neighbor is not the win it’s supposed to be.
A Real Comparison: Two Eagle Backyards, Two Different Results
A homeowner in Eagle planted a row of ‘Green Giant’ arborvitae along an exposed back fence line with no windbreak, watering with a standard lawn sprinkler zone rather than dedicated drip irrigation. Within three years, the row had noticeable brown, thin patches on the windward side, and two trees needed full replacement, an unplanned cost of about $600 for replacement stock and reworked irrigation.
A few streets over, another homeowner facing a similar privacy need chose Austrian pine instead, spaced properly at 18 feet, with drip irrigation set up at planting. The growth was slower to establish, no visible screening improvement for the first two years, but by year five the pines were providing full, reliable coverage with zero winter dieback or wind damage, and no replacement costs. The total planting cost was similar between the two projects, but the second homeowner got a permanent result instead of an ongoing repair project.
Establishment Watering: The Part Most People Skip
Almost every privacy screen failure we get called out for traces back to watering in the first two to three years, not the species choice itself. A newly planted tree, no matter how well-suited to Boise’s climate at maturity, has a limited root system right after planting and cannot yet reach the deeper soil moisture that lets an established tree tolerate our dry summers.
For a new privacy row, we recommend dedicated drip irrigation rather than relying on an existing lawn sprinkler zone. Lawn sprinklers are designed to wet the top few inches of soil for grass roots, which trains a young tree’s roots to stay shallow and encourages exactly the kind of wind vulnerability and drought stress that undermines the “wind-hardy” species on this list before they ever get the chance to prove it. A slow, deep soak two to three times a week during establishment, tapering to less frequent but still deep watering as the tree matures, gives you a stronger root system and a better-looking screen in half the time.
Mulch matters here too. A 3 to 4 inch ring of mulch around the base of each new tree, kept away from direct contact with the trunk, conserves soil moisture and moderates the temperature swings in our clay soil that stress new roots. Skipping mulch on a new privacy planting is a small omission that shows up as a big difference in survival rate three summers later.
Rural and Acreage Properties: A Different Kind of Screen
Everything above assumes a standard residential lot with a fence line and a neighbor on the other side. If you’re on a larger acreage property in the Treasure Valley looking for wind protection as much as visual privacy, a single-species row often isn’t the right approach at all. A multi-row windbreak design, mixing species and staggering rows, handles wind loading and establishment differently than a tight suburban privacy screen. We cover that specific approach, spacing, and species mix in our guide to windbreak trees for Treasure Valley properties, which is worth reading before committing to a single row if your property has more room and more wind exposure to work with.
If You Need Screening Faster Than Any Tree Can Deliver
Sometimes the honest answer is that no tree, fast-growing or not, will give you real privacy within the first year or two. In that case, we usually recommend either accepting a temporary fence or lattice screen while trees establish, or planting a mixed row with larger, more mature nursery stock up front (at higher upfront cost) rather than betting everything on rapid growth. A mixed-age planting, some larger specimens now, filled in with smaller and cheaper stock between them, often gets you usable privacy faster and more reliably than an entire row of small, fast growers planted at once.
Frequently Asked Questions
What is the fastest-growing privacy tree that actually survives in Boise? Hybrid poplar and ‘Green Giant’ arborvitae are the fastest reliable options, adding 3 to 6 feet a year under good conditions. Both need proper site prep and consistent watering to hold up long-term in our climate.
Is arborvitae a good choice for Boise’s wind? It can work, but it’s not the most wind-hardy option. On exposed sites facing prevailing wind, Austrian pine or Colorado blue spruce generally hold up better with less risk of browning or blowdown.
How far apart should I plant privacy trees? It depends on the species and how solid a screen you want. Faster-filling species like arborvitae go 6 to 10 feet apart, while larger trees like Austrian pine need 15 to 20 feet to reach full size without crowding.
Do fast-growing trees always have weak wood? Not always, but it’s a strong pattern. Some fast growers, like hybrid poplar, have meaningfully better wood strength than others, like Lombardy poplar or silver maple. Growth rate alone isn’t a reliable guide; species-specific wood strength matters more.
How much does it cost to plant a privacy row in Boise? It varies widely by species, size at planting, and how many trees you need. Smaller nursery stock might run $50 to $150 per tree installed, while larger, more mature specimens for immediate screening can run several hundred dollars or more each.
Can I mix evergreen and deciduous trees in a privacy screen? Yes, and it’s often a smart approach. Evergreens give year-round coverage while faster deciduous species fill gaps for a summer screen sooner. Just make sure spacing accounts for each species’ mature width.
What should I plant instead of arborvitae if my yard is very windy? Austrian pine is our most common recommendation for wind-exposed sites needing a dense evergreen screen. It’s slower to establish than arborvitae but far more resistant to wind damage and browning.
Get a Screen That’s Still Standing in Ten Years
The fastest tree isn’t always the right tree, especially in a climate that tests wood strength and root systems every spring. If you’re planning a privacy planting, our ISA-certified arborists can walk your site, account for your specific wind exposure and soil, and recommend a mix that gives you real coverage without a redo down the line. Not sure yet what a full planting and setup would run for your yard? Our cost calculator is a quick way to get a ballpark before you call.
Call (509) 351-8404 or request your free consultation online.