The 500 Square Foot Landscape Line
Most ADU plan sets in Solana Beach carry a small table about landscape area. One number in it decides whether you also need a licensed landscape package. Here's how to read it before you design the yard.
Published Nov 11, 2026
An ADU is a building project. In Solana Beach it can also turn into a landscape project on paper, and that surprises people.
The city's ADU submittal handout (June 2025) asks every applicant to break the lot down by surface type. Then it asks one more question: how much new or replaced landscape does this project touch? Past 500 square feet, a full landscape package joins the submittal.
So it pays to know where you stand early. Here's the short version, then the detail.
The table on your site plan
The handout asks for a breakdown of the property, existing and proposed, in these rows:
| Row | What it covers (per the handout) |
|---|---|
| Non-landscaped area | Building footprints, decks, patios, walks, driveway, parking and other hardscape |
| Non-irrigated landscape | Unwatered areas set aside from development, such as native open space |
| Irrigated landscape | Planting that gets water |
| Water features | Ponds, fountains, spas and swimming pools |
| Decorative hardscape | Rock, stone or pervious surfaces like decomposed granite next to planting |
| Total lot area | The sum |
A second, smaller table covers only the area of work. It adds up new or replacement irrigated landscape, water features and decorative hardscape tied to the project. That total is the aggregate landscape area.
If it's over 500 square feet, the handout says a landscape package is required.
What counts toward the 500
Three things count: planting you'll water, any water feature, and decorative hardscape such as gravel or decomposed granite placed beside planting.
What doesn't count is the footprint of the ADU itself, its patio, the walk to its door, or the driveway. Those sit in the non-landscaped row. The handout ties that row to criteria in Solana Beach Municipal Code section 17.56.150, so a designer should confirm how a given paver or deck surface is classed.
Areas you leave alone also stay out of the area-of-work number. If a mature hedge and its drip line aren't touched, they aren't part of this project's aggregate figure.
Why projects cross the line without meaning to
The ADU itself rarely pushes a project over. The work around it does.
- Trenching for sewer, water and power runs through planting beds, and those beds get replanted.
- Grading for drainage reshapes lawn and slopes that then need new cover.
- A new path, side yard gravel and a few planters add up faster than they look.
- Owners often redo the backyard while the crew is already there.
None of that is wrong. It just means the 500 figure should be estimated during design, not discovered at plan check.
What a landscape package contains
When one is required, the handout says the plan must be prepared by a licensed landscape architect, licensed civil engineer, licensed architect, or another landscape professional licensed by the state. It lists these pieces:
- Planting plan. Specific trees, shrubs and groundcovers on a plan, not a list of maybes. The legend gives botanical names, WUCOLS IV water use ratings, mature heights for trees and large shrubs, and installation sizes.
- Water conservation plan. A drawing of hydrozones, each with its irrigation type and plant factor, plus a completed ETWU/MAWA chart.
- Irrigation plan and legend, with every piece of equipment identified.
- Planting and irrigation details and specifications.
- Soils management report.
- Maintenance schedule for planting and irrigation.
- Irrigation schedule showing run times and water use.
The handout points to SBMC Chapter 17.56, the city's Water Efficient Landscape Regulations, for the full rule. It also notes that, when a package is required, the plans go to the city's third-party landscape reviewer in addition to the usual departments.
The state rule behind it
California's Department of Water Resources maintains the Model Water Efficient Landscape Ordinance, known as MWELO. DWR says about 40 percent of the water Californians use at home goes outdoors. Every local agency must adopt MWELO or its own ordinance that is at least as effective, and many write stricter versions. The latest MWELO amendments took effect January 2, 2025.
Two terms from that system show up on the Solana Beach chart:
- MAWA, the maximum applied water allowance, is the water budget for the landscape.
- ETWU, estimated total water use, is what your design is expected to use.
The design has to come in under the budget. Plant choice and irrigation type are the main levers. DWR also publishes WUCOLS, the plant water-use list the handout names, so designers aren't guessing at ratings.
Ways to stay under, if you want to
Some owners want a lush garden and will happily do the package. Others would rather keep the submittal lean. Either is a fair choice. If you're aiming to stay at or under 500, a few design moves help:
- Limit replanting to what the trench and grading disturb.
- Keep the ADU patio and walks as true hardscape, confirmed against the code criteria.
- Leave healthy existing planting in place and mark it as outside the area of work.
- Phase a larger garden redo as its own later project, with its own review if needed.
Run the numbers with your designer before you commit. The table is simple, but an honest count matters more than a low one.
What the city can and can't do with landscape rules
State ADU law lets cities apply objective standards to ADUs, and landscape is one of the listed categories (Government Code section 66314(b)(1)). There are limits. HCD's ADU Handbook says open space and landscaping requirements can't be used to deny an ADU of at least 800 square feet with four-foot side and rear setbacks. It also says units built under Government Code section 66323 aren't subject to local open space and landscaping requirements in an ADU ordinance.
Those limits are about stopping or shrinking the ADU. The landscape package is about how new planting is watered. If you think your project qualifies for one of the protected paths, ask the planner at intake how the landscape table applies to it.
Drainage and planting go together
The engineering section of the same handout asks that roof drains flow into landscaped areas before water is collected and sent to the street. So planting near the ADU often does double duty. It takes roof runoff and slows it down.
That's worth planning with the grading and drainage design rather than after it. Our grading and drainage page walks through the site side.
Where this fits in the plan set
The landscape table lives on the site plan along with parking, drainage and setbacks. If you're also checking floor area, our post on the 60% line covers that worksheet. For design choices around the unit itself, see ADU design. Utility routes, which often decide how much yard gets dug up, are on the utilities page.
Four steps before you draw the yard
- Sketch the ADU, utility routes and grading.
- Mark every planted or graveled area those will disturb.
- Add any new planting, water feature or decorative gravel you want.
- Total it. Over 500 means bringing in a licensed landscape professional early.
Getting started
We work with verified contractors who build ADUs on Solana Beach lots and can help you size the yard work along with the unit. Request a Free Quote to start.
Sources (accessed Nov 11, 2026): ADU Submittal Process and Basic Plan Requirements (June 2025) (City of Solana Beach) · Model Water Efficient Landscape Ordinance (California Department of Water Resources) · Accessory Dwelling Unit Handbook (2026 update) (California Department of Housing and Community Development)