Washington · Nonprofit
ARBORETUM FOUNDATION
ARBORETUM FOUNDATION (Washington) receives grants from 66 organizations whose IRS filings report $10,030,389 to it, the largest being THE ALDARRA FOUNDATION ($5,846,985). 39 of them have funded it in more than one year.
- Revenue FY2025
- $7.9M
- Funders on record
- 66
- Grants received
- $10M
- Net assets
- $14M
What Arboretum Foundation does
Mission
The Arboretum Foundation promotes, protects, and enhances the washington park arboretum for current and future generations by strengthening and building a diverse and engaged community of donors, volunteers, and advocates.
As stated on its FY2025 Form 990.
Programs
The foundation provides annual funding to the university of washington botanic gardens to support ongoing horticultural care and maintenance to the washington park arboretum. This year's funding provided for 2 full-time arborists, the equivalent of 7 full-time gardener positions, and a plant propagator as well as important supplies and equipment.
$682,709 spentof which $543,095 as grants29% of program spendingCapital projects: the foundation expends funds in support of the arboretum's master plan, either through granting funds to partners at the university of washington botanic gardens and the city of seattle, or directly to outside vendors. Current year projects include japanese garden ishigaki wall construction planning and pacific pathways design, as well as ongoing rhododendron glen maintenance. Prior year work includes woodland meadow planning, japanese garden pavilion improvements, and the replacement of the tsutakawa gates at the entrance to azalea way.
$364,861 spentof which $252,808 as grants16% of program spendingEducation: as part of the foundation's mission to steward the arboretum for future generations, it provides volunteer opportunities, educational materials and funds for the k-12 programs run by partners at the university of washington botanic gardens. Programs include an outdoor preschool, summer camps, school field trips and two different high school intern programs. Funds raised help keep prices low, with scholarships available for all programs.
$188,981 spentof which $188,981 as grants8% of program spendingMore than 550 volunteers donated approximately 14,600 hours for the benefit of the arboretum during this fiscal year. The foundation hires staff to coordinate the volunteer garden stewards who care for the grounds, focused on the pacific connections gardens and azalea way. Foundation staff also oversee the volunteer-run plant donations nursery and greenhouse, which have programs to provide education and plants to the public. Foundation staff also coordinate a full slate of programming at the japanese garden, including arts-focused free first thursdays and programs for children on family saturdays.
$1,106,257 spentof which $19,186 as grants$301,898 earned by the program47% of program spending
The 4 programs described on its FY2024 Form 990, listed largest first by expense. Program spending in total: $2,342,808.
The organization over time
Each line starts at 100 in 2017, so what you read is the shape rather than the size: 150 means half as much again as 2017, 50 means half. The number beside each label in the key is where it ended. The shaded band is where the middle 50% of its peers' revenue would sit, given their growth.
Balance sheet
Total assets and total liabilities at each year end, in dollars. The largest one-year move in total assets was 2024 to 2025, from $12M to $14M (+23%).
How it's funded, over time
Each bar is one year's revenue split into where it came from, and every bar is the same height — these are shares, not amounts, so a year that raised twice as much looks the same size. Hover a bar for the split.
Government-grant reliance: 2021 5% · 2022 3% · 2025 4%. Grants only. Government contracts and fees sit inside program revenue.
65% of ARBORETUM FOUNDATION’s revenue is contributions — about as donation-reliant as the typical peer (88% for the typical peer).
Surplus & reserves
Operating surplus or deficit each year, and months of liquidity in hand. 2 of the last 9 reported years ran a deficit.
reserve
Leadership and staff
The officers, directors, trustees and key employees listed on each return. Joined and no longer listed compare each filing with the year before, matching people by surname and first initial; a year after a gap, or a roster under three people, has no comparison.
Chief executive
Jane Stonecipher
Executive director through december
As listed on its FY2025 Form 990.
The chief executive listed changed between the FY2017 and FY2018 filings.
Who funds it, year by year
2017 → 2023: the base broadened from 10 funders to 29 funders, grant income rose $110k → $2.1M.
14 of 66 of your funders are donor-advised or pass-through sponsors (tagged DAF) — 28% of grant dollars received. That money is really individual donors directing a sponsor; the institutions to cultivate are the non-DAF funders.
From the IRS filings of ARBORETUM FOUNDATION’s funders (the co-funder graph). Top 30 of 66 funders by total. Association, not causation. Trends are read to FY2023, the last fiscal year that has finished arriving. FY2024–FY2026 are still being filed and are shown unshaded; they do not move any figure on this page.
How concentrated its funding is
ARBORETUM FOUNDATION leans on a few funders — its largest provides 58% of grant income and the top three 79%; half comes from just 1 funder.
the vertical line marks half of all grant income — 1 funder to its left
30% of the income these shares are computed over arrives through pass-through sponsors or from payers whose filings do not say what kind of payment it is. Concentration is still measured over all of it, because the money is real; what it does not support is a claim about how many institutions have chosen to fund ARBORETUM FOUNDATION.
Largest funder’s share by year: 2017 45% · 2018 85% · 2019 89% · 2020 35% · 2021 62% · 2022 45% · 2023 81% — growing more concentrated.
“Effective funders” = inverse Herfindahl index (1 / Σ shareᵢ²) — the number of equal-sized funders that would give the same concentration. Trends are read to FY2023, the last fiscal year that has finished arriving. FY2024–FY2026 are still being filed and are shown unshaded; they do not move any figure on this page.
How long its funders stay
51% of ARBORETUM FOUNDATION's funders are still giving 3 years after their first grant; 59% give in more than one year at all.
Share of funders still giving k years after their first recorded grant, pooled across every acquisition cohort. A funder counts as retained in a year only if it made a grant that year. Measured to FY2023, the last fiscal year that has finished arriving — a funder cannot be counted as lapsed in a year most filers have not reached.
Where its funders are
88% of ARBORETUM FOUNDATION's grant income comes from Washington funders.
In-state vs out-of-state, by year
Funder states come from each funder’s own filing. $2.8M arriving through sponsors registered in 8 states is excluded from the map and the split above: a sponsor holds money on a donor’s behalf, so its registered address would place those dollars somewhere no donor need ever have been. Trends are read to FY2023, the last fiscal year that has finished arriving. FY2024–FY2026 are still being filed and are shown unshaded; they do not move any figure on this page.
Against its field
ARBORETUM FOUNDATION runs a healthier operating margin than three-quarters of the 1,209 environment nonprofits its size.
this organization peer median middle 50% of peers· 1,209 environment nonprofits $1M–$10M, FY2025
Organizations like ARBORETUM FOUNDATION
Organizations whose mission and program text most resemble this one, by semantic similarity over every organization in the US filings — the closest peers, and often the clearest route to shared or prospective funders.
In Washington
Nationally
Read directly from this organization’s own Form 990, as neutral context.
Where the money goes
65% of spending goes to programs.
Governance
Public support
48%
Share of support from the public (Schedule A) — the basis for its public-charity status.
Screen this organization
A dated, signed PDF of the compliance screen for ARBORETUM FOUNDATION: IRS status (Business Master File, Publication 78, auto-revocation), the OFAC sanctions lists, the Internal Revenue Bulletin, and California registration, with the Rev. Proc. 2018-32 §8.01 reliance elements stated element by element. Generated from the current files at the moment you download it.
Screens are triage, not determinations; a source that cannot be read reports not screened, never clear. Screen this nonprofit · How the screen works · on the API as GET /api/screening/{ein}?format=pdf
Questions and answers
- Who funds ARBORETUM FOUNDATION?
- ARBORETUM FOUNDATION (Washington) receives grants from 66 organizations whose IRS filings report $10,030,389 to it, the largest being THE ALDARRA FOUNDATION ($5,846,985). 39 of them have funded it in more than one year.
- How many funders does ARBORETUM FOUNDATION have?
- IRS filings report 66 organizations giving $10,030,389 in grants to ARBORETUM FOUNDATION, 39 of which have funded it in more than one year.
- Who is the largest funder of ARBORETUM FOUNDATION?
- THE ALDARRA FOUNDATION is the largest funder on record, with $5,846,985 in grants. The full list of funders is on this page.
- How can an organization like ARBORETUM FOUNDATION find more funders?
- Start with the funders already giving here, then look at the foundations that back similar organizations in Washington. The funding by cause and by state pages list the largest funders for a given area and how to approach them.
These figures are read directly from IRS Form 990 / 990-PF e-file XML: this organization’s own return for FY2025 (financials across 2017–2025), and the filings of 66 funders that report grants to it. “On record” means captured in the filings we have parsed — a funder that does not e-file, or whose grant detail is not itemized, will not appear. Filings run roughly 12–24 months behind. Trends on this page end at FY2023, the last fiscal year that has finished arriving; later years are shown and marked, and move no figure. Data on this page was exported October 22, 2026. What this page cannot tell you · view filing