What the C-27 Landscaping Contractor License Covers
The C-27 Landscaping Contractor classification authorizes a California contractor to construct, install, and maintain landscape systems and features. Section 832.27 of the CSLB Contractors License Law defines the C-27 scope as work that constructs, maintains, repairs, installs, or subcontracts the development of landscape systems and facilities for public and private gardens and other areas which are designed to aesthetically, architecturally, horticulturally, or functionally improve the grounds within or surrounding a structure or a tract or plot of land.
In practical terms, that means a C-27 licensee can grade and prepare landscape areas, install irrigation systems, plant trees, shrubs, ground cover, and lawns, build landscape walls and edging up to a regulatory height, install drainage and surface drainage devices in landscaped areas, construct walkways and decorative paving, install landscape lighting and low-voltage systems, build trellises, arbors, gazebos, and fences as part of a landscape installation, and install water features such as fountains and decorative ponds. C-27 is one of the most versatile of the C classifications, and one of the highest-volume on the CSLB exam calendar.
This guide walks through what to expect on the C-27 trade exam, where the scope boundary sits with adjacent licenses, the laws and codes most often tested, and a study plan that has worked for applicants in 2026. If you want to compare prep options, see the broader comparison on our CSLB exam prep courses page.
C-27 Eligibility Requirements
To qualify for the C-27 license, the CSLB requires at least four years of journey-level experience within the past ten years in the landscaping trade or in a closely related trade. Experience can come from work as a journeyman, foreman, supervising employee, contractor, or owner-builder. Education or apprenticeship completion can substitute for up to three of the four years.
You must also be at least 18 years old, have a valid Social Security number or Individual Taxpayer Identification Number, and pass two exams: the Law and Business exam (required for every classification) and the C-27 Landscaping trade exam. After passing both, applicants post a contractor’s bond, provide proof of workers’ compensation insurance (or sign a no-employees exemption), and pay the initial license fee.
The CSLB uses a sworn affidavit (a Certification of Work Experience) signed by someone who can vouch for your experience, typically a current or former employer, business partner, journeyman, foreman, project owner, or building inspector. Falsified experience is a felony and results in permanent denial, so this is one section of the application worth handling carefully.
The C-27 Trade Exam Structure
The C-27 trade exam is a closed-book, computer-based, multiple-choice test administered at CSLB testing centers in Berkeley, Fresno, Norwalk, Oakland, Oxnard, Sacramento, San Bernardino, San Diego, San Jose, and Santa Fe Springs. Applicants are given three and a half hours to complete the exam. The CSLB does not publish the exact number of questions, but the C-27 trade exam typically falls in the 100 to 115 scored-question range, with a small number of unscored pretest items mixed in.
The passing score is set by examination through a process called modified Angoff. The published threshold is the same scaled score across CSLB classifications, but the underlying raw cut score varies by exam form. In practice, candidates who can answer roughly 72 to 75 percent of practice questions correctly under timed conditions tend to pass on the first attempt.
C-27 Exam Content Areas
The CSLB publishes a content outline for each trade exam, and the C-27 outline organizes the material into roughly the following knowledge areas. Percentages shift between exam revisions, but the categories have been stable for years.
Planning and Estimating
Reading and interpreting landscape plans, including planting plans, irrigation plans, hardscape plans, and grading plans. Understanding planting symbols, irrigation symbols, scale, contour intervals, spot elevations, and section details. Calculating material quantities for soil, mulch, sod, plants, irrigation components, base material, decorative gravel, and concrete. Estimating labor hours, equipment costs, and overhead. Producing a written bid that meets the Business and Professions Code disclosure requirements.
Site Preparation and Grading
Site evaluation: identifying existing utilities, drainage patterns, soil conditions, slope, and access constraints. Calling DigAlert (USA North 811) at least two working days before any excavation. Establishing finish grades that drain away from structures. Selecting the right equipment for the site (skid steer, mini excavator, hand tools), and operating it safely. Understanding the limits of the C-27 scope on grading (incidental to landscape work) versus when a C-12 Earthwork and Paving classification is required.
Irrigation Systems
Designing, installing, and repairing automatic irrigation systems. Sizing pipe based on flow rate, velocity, and pressure loss. Backflow prevention requirements under Title 17 of the California Code of Regulations and local water purveyor rules. Sprinkler head selection (rotor, spray, rotary nozzle, drip), spacing for head-to-head coverage, and matching precipitation rates. Controller programming and the Model Water Efficient Landscape Ordinance (MWELO), which applies to new and rehabilitated landscapes meeting size thresholds. Smart controllers and weather-based scheduling.
Planting
Plant identification, hardiness zones in California, and selecting plants appropriate to climate, exposure, and water budget. Soil testing and amendments. Planting techniques for container-grown trees and shrubs, bare-root stock, and sod. Staking and tree protection. Mulching depth and clearance from trunks. Right plant, right place principles, and California Friendly and California Native plant palettes used in MWELO compliance.
Hardscape and Construction
Concrete walkways, mortared and dry-laid stone paving, segmental retaining walls, wood and composite decking as part of a landscape, low fencing, arbors, trellises, pergolas, and outdoor kitchens within the landscape contractor scope. Knowing the regulatory height threshold for retaining walls and when the work requires a separate engineered design or a different classification.
Drainage
Surface drainage, swales, French drains, area drains, channel drains, dry wells, downspout connections, and stormwater management. Compliance with local stormwater pollution prevention plan requirements during construction. Understanding the difference between landscape drainage (within C-27 scope) and storm drain piping connected to a public storm sewer.
Landscape Lighting and Low Voltage
Installing low-voltage landscape lighting (less than 90 volts), including transformers, wire sizing for voltage drop, and fixture placement. Understanding the boundary with the C-10 Electrical classification for line-voltage work.
Safety
Cal/OSHA general industry and construction safety orders applicable to landscape work. Trenching and excavation safety, particularly when working around irrigation mainlines or gas service lines. Personal protective equipment, heat illness prevention (Title 8 Section 3395), and chemical safety for pesticide and herbicide application. Note that pesticide application for hire requires a separate Qualified Applicator License or Certificate from the Department of Pesticide Regulation; a C-27 license alone does not authorize chemical pest control work.
Where the C-27 Scope Ends
One of the more commonly tested topics on the trade exam is the boundary between C-27 and other classifications. Knowing where your license stops is part of being a competent landscape contractor.
- C-27 versus C-10 Electrical: Low-voltage lighting (under 90 volts) is C-27. Anything line-voltage, including the panel circuit feeding a low-voltage transformer, is C-10.
- C-27 versus C-36 Plumbing: Irrigation mainlines and laterals downstream of the irrigation backflow device are C-27. The water service connection to the meter, domestic water service, and any modification to the building’s water supply are C-36.
- C-27 versus C-29 Masonry: Landscape retaining walls and decorative masonry incidental to the landscape are within C-27 scope up to specified height thresholds. Structural masonry, taller retaining walls, and masonry that supports a structure are C-29 or B (general building).
- C-27 versus C-12 Earthwork and Paving: Grading incidental to landscape installation is within C-27 scope. Standalone grading, lot preparation, or paving as a primary scope of work is C-12.
- C-27 versus C-53 Swimming Pool: Pools, spas, and the equipment serving them require a C-53. Decking, landscape lighting, and planting around a pool can be C-27 if the pool work is contracted separately to a C-53.
If you anticipate doing significant work outside the C-27 scope, plan to add a classification or work under a properly licensed subcontractor. Adding a classification requires the same exam process for the additional trade exam; the Law and Business exam is only taken once.
California Codes and Laws Most Tested on the C-27 Exam
Beyond the trade content, the C-27 exam pulls heavily from the regulatory framework that governs landscape work in California. The Model Water Efficient Landscape Ordinance (MWELO), codified in Title 23 of the California Code of Regulations, applies to new and rehabilitated landscapes that meet the size threshold (currently 500 square feet for new construction permit applications and 2,500 square feet for rehabilitated landscapes that require a permit). MWELO requires a Landscape Documentation Package, hydrozone-based irrigation, soil management, and certificates of completion.
Backflow prevention rules under Title 17 require approved backflow assemblies on irrigation systems where there is any potential for cross-connection. Local water purveyors may add stricter requirements. The California Plumbing Code, Chapter 6 (Water Supply and Distribution), covers piping materials, installation, and testing for the portion of the irrigation system upstream of the irrigation valves.
The Healthy Schools Act regulates pesticide use on school grounds and is a common exam item. The Underground Service Alert (USA North 811) statute requires excavators to notify before digging. Cal/OSHA requirements on trenching, heat illness prevention, and fall protection are tested. The Business and Professions Code, including Sections 7159 (home improvement contracts), 7048 (minor work exemption), 7068 (qualifying individual), and 7071 (contractor’s bond requirements), is the same body of law tested on the Law and Business exam but referenced on the trade exam in the context of landscape contracts.
A Realistic C-27 Study Plan
The C-27 exam rewards a combination of field experience and structured review. A four to six week plan works for most candidates with full-time work and family responsibilities.
Weeks One and Two
Read through a focused C-27 study guide cover to cover, slowly. Highlight unfamiliar concepts and code references. Take a baseline practice exam under timed conditions to identify weak content areas. Most candidates score in the 50 to 65 percent range on a first baseline.
Weeks Three and Four
Spend each study session on a single content area. Read the relevant chapter of the study guide, answer 40 to 60 practice questions from that area, and review every wrong answer. The review is more important than the score. If you got a question wrong because you misread it, that is one issue. If you got it wrong because you genuinely did not know the underlying code reference, that is a study target.
Weeks Five and Six
Take two full-length timed practice exams per week, mixing all content areas. Track your performance by category. By the end of week six you should be in the 78 to 85 percent range on full-length practice exams. The day before the real exam, do a light review of any remaining weak areas and stop studying by early evening. Sleep matters more than another hour of cramming.
Browse all 45 single-class trade exam study packages on the browse all classifications page; each includes a study guide and four practice exams calibrated to the current CSLB content outline.
Frequently Asked Questions
How much does the C-27 license cost in total?
The CSLB application fee is $450 and the initial license fee after passing both exams is $200, for $650 in state fees. Beyond that, expect costs for a contractor’s bond (typically $150 to $400 per year depending on credit), workers’ compensation insurance if you have employees, general liability insurance (commonly required by clients), and any study materials you purchase.
Can I do landscape design work with a C-27?
A C-27 license authorizes you to construct and install landscape systems. Standalone landscape architectural design services are regulated by the Landscape Architects Technical Committee under the Department of Consumer Affairs and require a separate Landscape Architect license. Many C-27 contractors collaborate with licensed landscape architects on larger projects and produce their own simpler installation drawings for smaller residential jobs.
Do I need a separate license to apply pesticides?
Yes. Applying pesticides or herbicides for hire requires a Qualified Applicator Certificate or License from the California Department of Pesticide Regulation, regardless of your contractor classification. Many landscape contractors hold both credentials so they can offer integrated maintenance services.
How long is the C-27 trade exam?
Three and a half hours, in addition to the Law and Business exam, which is also three and a half hours. Most candidates take both exams on separate days. You can attempt each exam up to four times within an 18 month application window before reapplying.
Is the C-27 exam harder than the Law and Business exam?
The two exams test different things. The Law and Business exam tests breadth across the Business and Professions Code, contract law, accounting basics, mechanics liens, labor law, and safety. The C-27 trade exam tests depth in landscape construction and the codes that govern it. Candidates with field experience often find the trade exam more familiar; candidates with administrative or office backgrounds often find the Law and Business exam more familiar.
Can I take the trade exam first and the Law and Business exam later?
Yes. You can take the two exams in either order. Both must pass within the 18 month application window. Many candidates schedule the trade exam first because their field knowledge is already strong, then study for and take the Law and Business exam second.
Ready to get started?
Whether you are coming up on your application window or already scheduled to test, the right preparation makes the difference between a single attempt and multiple retakes. If you want help mapping the path from application to active license, talk to a licensing specialist and we will walk you through experience documentation, exam scheduling, and what to expect on the C-27 trade exam.