Join our vibrant and diverse community of Arboretum champions!

Volunteer with us and help maintain and enhance one of the Pacific Northwest’s great treasures: Washington Park Arboretum. Volunteering here is a wonderful way to build community, protect your local environment, earn community-service credits, spend time outdoors, and increase your knowledge of plants and trees.

Please contact our volunteer department with questions at volunteer@arboretumfoundation.org or 206-325-4510.

Arboretum Garden Stewards

Volunteer Garden Stewards assist staff gardeners with the monumental task of maintaining the Arboretum, through weekday weeding and mulching sessions. This program is great for anyone who wants to garden, support the Arboretum, build community, learn about plants, and/or just get some quality time in the dirt for a good cause! With no requirement for how often you must participate, it is well suited for people with time constraints that make regular volunteer commitments challenging.

When: Mid-March to mid-November, on Tuesday and Thursday mornings, from 9 a.m. to 12 p.m.


  • Volunteers register for a work party using an online calendar, based on their availability.
  • Volunteers should arrive at the start time of the session, and are asked to stay for at least 2 hours.
  • There is no commitment for this program! Volunteers may attend work sessions as frequently as they can. 
  • You are encouraged to join at least twice a month—to stay connected with the team and keep building your weeding and plant identification skills. 
  • Please bring your own work gloves.
  • No gardening experience necessary. Tools and training are provided!
  • You must be at least 14 years old to volunteer with the stewards. Youth ages 14 to 17 also must provide proof of age and complete an authorization form signed by a legal guardian in order to volunteer. (Contact us via email, and we’ll send you the form.)

Please email our Garden Stewards Assistant, Jana Robbins, if you are interested in joining the Garden Stewards Program.

Corporate & Group Service Program

Bring your team out to the Arboretum to participate in a service project! Our Corporate & Group Service projects are an excellent way to invest in your local community, create opportunities for team bonding and problem solving, engage with nature, and learn about the Arboretum.

The projects involve working out on the grounds to weed, remove invasive species, and/or complete mulching projects in our collection. Our knowledgeable staff will provide the necessary tools and direct your group in the tasks to be accomplished. We will work alongside you to ensure that everyone feels comfortable and is provided with educational opportunities. 

When: Service projects are typically 3-hour sessions held Wednesday to Friday from 9 a.m. to 12 p.m. Please email our volunteer programs manager to schedule a project with us—at least 2 weeks in advance of requested date.

Donations: While our projects are free of charge, we encourage donations of any amount to help offset the cost of materials and project coordination—and to support the Arboretum! If your company has a budget for community work, we’d love to discuss a potential donation with you.

Mary Ellen Mulder Arboretum Gift Shop - Cashier

Volunteers who enjoy greeting guests, customer service, and getting to know fun and unique merchandise, will love being a cashier in our Gift Shop! The shop opened in 1985 and has been staffed by volunteers since the beginning. We sell a nice variety of cards, gifts, books, art, jewelry, gardening supplies, and more. All sales help fund plant care, education, and volunteer services at the Arboretum. Cashiers are provided with training and support, plus ample opportunity to get to know the Arboretum staff and build a new community!

When: [BUILDING CLOSURES DUE TO COVID HAVE CHANGED THE GIFT SHOP HOURS – Please email volunteer@arboretumfoundation.org for more information]

Gift Shop volunteer shifts are daily, from 9:30 a.m.– 1 p.m. and 1 p.m.– 4:30 p.m. The Shop is open from 10 a.m. to 4 p.m. Most of our weekday volunteers have a regular schedule every month, but we also have individuals who cover shifts on a fill-in basis. We are currently in need of volunteers who are available on some Thursdays, Fridays, and weekends.

Responsibilities include: Opening and closing the shop; running our cash register system (Square); handling and counting money; preparing the deposit at the close; helping customers and answering questions; stocking and tidying the shelves; and light administrative work.


  • Volunteers must commit to 2 shifts per month, for at least 6 months. Note: weekend volunteers need only commit to 1 shift per month. 
  • Volunteers must be at least 18 years old. 
  • Volunteers must be at ease in a customer-service role; comfortable handling and counting money; ready to learn a Square register system; and able to work independently but willing to ask for help when needed.

Pat Calvert Greenhouse

Join the team that propagates plants to support the Arboretum! The Pat Calvert Greenhouse is a volunteer-run greenhouse that sells young trees, shrubs, perennials, and bonzai starts grown from seeds or from cuttings taken primarily from Arboretum collection plants. All sales fund horticulture, education, and volunteer programs in the park. The greenhouse volunteers are a community who value and support the Arboretum, as well as one another. Every fifth Tuesday, they host a potluck lunch so team members can spend more time getting to know one another!

Responsibilities include: Greenhouse volunteers propagate, care for, weed, groom, and repot plants grown from seed or cuttings. Volunteers maintain a sales area and create seasonal displays of plants, as well as a perennial border garden.

Don’t have a green thumb? No problem! The Greenhouse volunteers have two teams: one focused on propagation, the other on nursery-maintenance tasks such as watering, weeding, organizing plants, and creating signage. 

When: Volunteer sessions are Tuesday and Thursday mornings, from 10 a.m. to 12 p.m. Note: From November to March, sessions are reduced to Tuesday mornings only.


  • Volunteers are asked to commit to 3 sessions per month, for at least 6 months. 
  • No experience is necessary! Many join to learn the tricks of the propagation trade.
  • Tools and gloves are provided.
  • Volunteers must be at least 17 years old to work without a guardian present. 

Learn about the history of the Pat Calvert Greenhouse.

Cloney-Harris Plant Nursery

The Cloney-Harris Plant Nursery is a pillar of the Seattle horticultural community, providing a resource for gardeners to recycle shrubs and flowers from their gardens and give the plants a second life at someone else’s home. A volunteer-operated nursery, it accepts donated plants from the local community and resells them to raise money for the Arboretum.

The Nursery is currently at capacity and not accepting new volunteers. Please keep it in mind for the future!

When: Wednesdays, from 10 a.m. to 2 p.m., April to early October. The group takes a break for lunch at noon to enjoy each others’ company around a large picnic table.

Responsibilities include: Volunteers work outdoors to repot, groom, water, and provide general care for the plants. Volunteers weed the nursery area, maintain a sedum garden, and move large plants and soil around the nursery. Some stooping, bending, and lifting required. Volunteers also work with customers dropping off or shopping for plants.


  • Volunteers are asked to commit to at least 2 sessions per month. 
  • Some experience identifying and caring for plants is strongly preferred. 
  • Volunteers must be at least 18 years old to volunteer.
  • Aprons, gloves, and tools are provided.

Events and Projects

There is a mighty volunteer force behind all Arboretum Foundation events! Join the team that makes the magic happen!

We host or co-host a number of special events each year, including our Earth Day at the Arboretum work party, Plant and Holiday sales, an Opening Night Party, and a Display Garden at the Northwest Flower and Garden Festival. We need volunteers to assist with these events for tasks such as set up, cashiering, silent auction coordination, portering, and clean up. For the Earth Day event, we need volunteers to join us out on the grounds of the Arboretum, weeding and mulching in the collections.

When: These volunteer opportunities come up throughout the year, and the best way to stay involved and informed is to sign up for our volunteer e-newsletter!

Age Requirement: Varies depending on each event or project. Typically, volunteers under the age of 15 will need a parent or guardian present.

Admin and Office Volunteering

The Arboretum Foundation is looking for detail-orientated administrative and event-prep volunteers to help at our office!

When: Flexible between Monday and Friday. We’re looking for volunteers to commit to 3 to 6 hours per week between the hours of 10 a.m. and 4 p.m.

Special Skills Volunteering

Do you have a specific skill not represented in our main programs that you’d like to offer to the Arboretum in a volunteer capacity? Would you like to assist with event photography, create merchandise displays in the Gift Shop, or work on some graphic design? These are just a few examples of skills that you could donate to help our mission.

Please note “skilled volunteering” on your volunteer application, or email volunteer@arboretumfoundation.org and let us know about a volunteer task you’d like to take on for the Arboretum.

Amazon volunteers show off their dirty gloves during a work session