Frequently Asked Questions

Our design process typically takes 4 to 6 weeks. It begins with an initial consultation where we walk your property, discuss your goals, and gather information about your site.

After the design deposit is received, we develop 2 to 3 concept drawings that explore different layout and design possibilities. From there, we refine the concepts into a preliminary design plan and plant list — defining the overall structure, spatial organization, pathways, and key garden areas.

Finally, we deliver a comprehensive masterplan drawing and detailed plant list. The plant list includes cultural and maintenance information for each species, so you know exactly what’s going in the ground and how to care for it.

For larger projects, yes — we strongly recommend some form of design before breaking ground. For smaller or more straightforward installations, some elements can be designed in the field by our team.

We walk your property together, discuss your vision, priorities, and site challenges, and explore creative options tailored to your space. It’s a conversation, not a sales pitch.

Yes. For design, construction, and RainWise consultations, we charge a small consultation fee. That fee is refundable when you sign a contract and pay a deposit for the work.

Our design package includes a construction-ready masterplan, a detailed plant list, and an installation estimate for your project.

Both, depending on the project. The 2D masterplan is the primary document used for installation. The 3D rendering gives you a visual representation of the finished space with all design elements and plants shown at maturity.

Yes. Every design is a collaborative process. We work closely with you throughout to make sure the finished plan reflects your goals and feels right for your property.

Yes. Washington summers are often warm and dry, with little rainfall for several months. An irrigation system ensures your plants receive consistent moisture during the growing season, promoting healthier growth and reducing stress from drought.

Modern systems can be designed for water efficiency, delivering the right amount of water only where and when it’s needed.

Each site is different. We evaluate conditions during the initial site visit and again during the installation phase. Solutions vary based on what we find — there’s no one-size-fits-all answer for drainage or grading.

Yes. Trillium is a certified RainWise contractor through Seattle Public Utilities. We install rain gardens and cisterns for homeowners in qualifying Seattle neighborhoods and help clients navigate the city’s rebate program.

We select plants based on your site conditions — sun exposure, soil type, drainage, and microclimates — as well as your design goals: preferred style, seasonal interest, maintenance preferences, and how you plan to use the space.

Our plant selections are tailored to the Pacific Northwest climate, with a strong emphasis on native, pollinator-friendly, and drought-tolerant species that thrive long-term.

Yes. Our goal is to create sustainable, healthy gardens. We specialize in native, pollinator-friendly, and drought-tolerant species that support the local ecosystem and hold up through Pacific Northwest seasons.

Gardens can be designed to be lower maintenance, but no garden is maintenance-free. Especially when young, gardens need routine care to prevent weeds from overtaking new plants and regular watering to ensure survival. Most gardens take 3 to 5 years to fill in and begin requiring less intervention.

We incorporate evergreen foliage, plants that bloom at different times of year, shrubs with distinctive form and structure, and integrated hardscape elements. The goal is a garden that looks good in January as well as June.

Both. Trillium is a design-build company. We can take a project from the initial design concept all the way through construction and planting.

Typically, no. We prefer to keep everything in-house to ensure quality and continuity. The exception is work that falls outside our scope — such as specialized trades Trillium doesn’t perform.

Design-only services produce a complete landscape plan: layout, materials, and planting design. You receive a detailed masterplan you can use to obtain bids from contractors of your choice.

Design-build combines both design and installation under one team. After the design is finalized, the same company manages construction and planting — a more streamlined process from concept to completion.

Yes. We warranty plants for one year after installation, provided there is a functioning irrigation system installed or evaluated by our irrigation professional.

A standard project from design through installation can range from $10,000 to $50,000 or more depending on scope. Design services start at $2,000. Planting projects typically start at $8,000. Stonework and hardscaping start at $10,000. Irrigation work, performed by our partner Backflow and Irrigation Solutions LLC, ranges from $8,000 to $15,000.

The more elements incorporated, the higher the total investment.

The biggest factors are the size and complexity of the site, scope of design and installation, and materials selected. Hardscaping elements — patios, walkways, retaining walls, drainage systems — add to the overall cost, as do mature trees, specialty plants, and custom features.

Site conditions also play a role. Sloped properties, poor soil, or drainage challenges may require additional preparation. Access, labor, and level of design detail all influence the final number.

Yes. After our initial consultation, we provide an estimate for the work discussed before any project begins.

For larger projects, we are typically booked 3 to 6 months out. Smaller projects can sometimes be scheduled sooner on a case-by-case basis.

It depends on the size of your property, the types of plants, and the season. Most gardens benefit from professional maintenance every one to four weeks. Regular care keeps plants healthy, controls weeds, maintains proper pruning, and ensures irrigation systems are working efficiently.

We can recommend a maintenance schedule tailored to your property’s specific needs.

Yes. We love maintaining the gardens we install. After installation, we discuss a maintenance plan based on the garden’s specific needs and your preferences.

Yes. As part of our maintenance service, we can provide guidance on plant care or handle it for you. Irrigation is monitored by our maintenance crew or managed by our irrigation specialist depending on what you need.

Consistent seasonal care is the foundation: regular watering during dry periods, proper mulching, and timely pruning. A professional maintenance plan takes that off your plate and keeps the garden performing the way it was designed to.

Our approach is plant-forward. Rather than starting with hardscape or decorative features, we prioritize thoughtful planting design that feels natural, layered, and well-adapted to the Pacific Northwest climate.

We focus on cohesive, lower-maintenance landscapes that combine structure, seasonal interest, and sustainability. Every design is tailored to the property and client goals, with careful attention to how the garden will evolve over time.

Residential. That’s where our focus and experience are.

Yes. We regularly work with existing landscapes — refreshing, refining, or reimagining them depending on your goals. This may include improving plant health and structure, updating outdated planting, enhancing seasonal interest, or addressing drainage, irrigation, or layout issues.

Whether the goal is a full redesign or targeted improvements, we build on what’s already working and make thoughtful changes that improve cohesion and long-term performance.