Planting Plans and Plant Schedules: How to Read and Make Them

A planting plan turns a design idea into something a nursery can supply and a crew can install. It answers four questions precisely: which plants, how many, what size, and exactly where. The plant schedule that accompanies it is the shopping list and the quality standard rolled into one.

Whether you are drawing a plan for your own yard or reading one from a designer, knowing how these documents work saves money and prevents the familiar problems of plants that do not fit, quantities that run short, and planting done at the wrong time of year. This guide covers the contents of a planting plan and schedule, how to count plants for mass plantings, and how to time installation and aftercare.

What a planting plan shows

A planting plan is a scaled drawing of the site showing the position of every plant or plant group. A complete plan normally includes:

• Base information: property boundary, buildings, hardscape, existing trees to remain, and a north arrow
• Scale and dimensions: a written and graphic scale, and dimensions to key plants where accuracy matters
• Plant symbols: circles or shapes sized to represent each plant's mature spread
• Labels: a code for each plant or group, often with a quantity, such as "VD 5" for five Viburnum dentatum
• Bed outlines and areas for masses and groundcovers, labelled with code and spacing
• Notes: soil preparation, mulch type and depth, edging, and any protection for existing trees

Plant symbols

Symbols are usually drawn at mature spread, not planting size. That is how a plan shows whether plants will fit together. Common conventions:

• Trees: large circles, often with a centre point marking the trunk; evergreen trees may have a jagged or textured outline
• Shrubs: smaller circles, sometimes linked by a line when grouped
• Perennials and grasses: small circles or dots for individuals; a hatched or outlined area for masses
• Groundcovers: a pattern fill across the bed with a code and spacing

Existing plants to remain are usually shown with a different line weight or a dashed outline, and plants to be removed are often marked with an X.

What a plant schedule contains

The plant schedule (also called a plant list or plant legend) is a table, usually on the same sheet as the plan. Typical columns:

Install sizes follow nursery conventions: containers by nominal volume (such as 1-gallon or 3-gallon pots, sometimes labelled #1 or #3), trees by trunk caliper or height, and plugs or flats for groundcovers. In the United States, the ANSI Z60.1 American Standard for Nursery Stock defines these grades. Note that a "1-gallon" container typically holds less than one liquid gallon; it is a trade size.

Always use scientific names. Common names vary by region, and one common name can refer to several species. If a specific cultivar matters, for size, colour or form, write it out in full.

Counting plants from area and spacing

For individual trees and shrubs, quantity is just a count of symbols. For masses and groundcovers, you calculate quantity from bed area and spacing.

Square spacing

On a square grid, each plant occupies a square of side s (the on-centre spacing). The number of plants is:

plants = area ÷ s²

Triangular spacing

On a triangular (offset or staggered) grid, each row is shifted by half a spacing and rows are closer together, at s × 0.866 (that is, s × √3 ÷ 2). Each plant occupies an area of s² × 0.866, so:

plants = area ÷ (s² × 0.866), which is about 1.155 × area ÷ s²

Triangular spacing places about 15 percent more plants in the same area at the same on-centre distance, gives more even coverage, and avoids the regimented look of straight rows. It is the usual choice for groundcovers and naturalistic masses.

Worked example

A bed of 20 m² planted at 45 cm on centre:

• Square: 20 ÷ 0.45² = 20 ÷ 0.2025 ≈ 98.8, so 99 plants
• Triangular: 20 ÷ (0.2025 × 0.866) ≈ 114.0, so 114 plants

The same calculation in imperial units, for a 200 sq ft bed at 18 in (1.5 ft) on centre:

• Square: 200 ÷ 2.25 ≈ 88.9, so 89 plants
• Triangular: 200 ÷ (2.25 × 0.866) ≈ 102.6, so 103 plants

Quick reference

Round up, and subtract the area taken by trees, shrubs or boulders within the bed before calculating. On small or narrow beds, edge effects mean the true count may differ from the formula; lay out the grid on the plan to check. The spacing tool does this calculation for you, and our guide to reading mature plant sizes explains how to choose the spacing in the first place.

Hedges and rows

For a row, divide the length by the spacing and add one: a 12 m (about 40 ft) hedge at 1.2 m (4 ft) on centre needs 12 ÷ 1.2 + 1 = 11 plants. Staggered double rows for denser screens need roughly twice that number.

Timing work to frost dates

Frost dates are the average dates of the last spring frost and first fall frost for your location. They are averages, so a frost after the "last frost date" is entirely possible. Many references note roughly a 50 percent chance of frost on or after the average last frost date, which is why gardeners often wait a week or two beyond it for tender plants. Local extension services publish frost dates and planting calendars for their areas.

General timing patterns:

• Trees and shrubs: in much of the temperate U.S., early fall and spring are the main planting windows. Fall planting gives roots time to grow in warm soil before winter. In hot climates, the cool season is usually preferred and midsummer planting is avoided.
• Perennials: spring after the last frost and early fall, at least several weeks before the ground freezes, are typical in cold climates.
• Tender annuals and frost-sensitive plants: after the last frost date, once soil has warmed.
• Spring-flowering bulbs: in fall, once soil has cooled.
• Seeding native meadows: often late fall or winter for species that need cold, moist stratification, or spring for warm-season grasses; follow the seed supplier's guidance.

Avoid planting in frozen, saturated or extremely dry soil, and during heat waves.

Establishment watering

New plants have small root systems and depend on regular watering until roots grow into the surrounding soil. Needs vary by plant, soil and climate, but common guidance:

• Water deeply at planting, settling soil around the root ball.
• Through the first growing season, keep the root ball and surrounding soil evenly moist, not waterlogged. Check by feel a few centimetres down; container root balls can dry out faster than the surrounding soil.
• Water deeply and less often rather than lightly every day, to encourage deeper roots.
• Trees and large shrubs often need supplemental watering for more than one season; extension guidance commonly suggests longer establishment periods for larger trees.
• Even drought-tolerant plants need regular watering until established.

Mulch beds to about 5 to 8 cm (2 to 3 in), keeping mulch away from stems and trunks. The EPA's WaterSense program has general guidance on efficient outdoor watering.

Maintenance calendar

A planting plan should come with a simple calendar for the first few years. A typical temperate-climate outline:

Adjust timing to your region's frost dates and rainfall. In hot, dry climates, much of this calendar shifts to the cooler months.

How OpenLandscape3D helps

In the web planner you can place plants individually or as rows, hedges, masses and grids, with spacing drawn from each plant's catalogue data. The planner exports a plant schedule CSV with code, scientific name, common name, quantity, install size, spacing, mature size and native status, and a seasonal task schedule CSV calculated from local frost dates. Design checks flag issues such as plants on hard surfaces (OL-ONHARD), plants outside the boundary (OL-OUTSIDE) and bloom gaps between April and October (OL-BLOOMGAP). The planner does not design irrigation; it checks water use and moisture only.

Frequently asked questions

What is the difference between a planting plan and a plant schedule?

The planting plan is the drawing showing where each plant goes. The plant schedule is the table listing each plant's code, name, quantity, size and spacing. Together they define the planting.

Should I use triangular or square spacing?

Triangular spacing gives more even coverage and a more natural look, and is standard for groundcovers and masses. Square spacing is simpler to lay out and suits formal or grid designs. Triangular spacing needs about 15 percent more plants.

How do I calculate how many plants I need for a bed?

Divide the bed area by the square of the on-centre spacing for square spacing, or by the square of the spacing times 0.866 for triangular spacing. Subtract areas occupied by other plants or objects and round up.

Is it safe to plant right after the last frost date?

Hardy trees, shrubs and perennials can usually be planted before it. For tender plants, the average last frost date still carries a real risk of frost, so many gardeners wait one to two weeks and watch the forecast.

How long do new plants need extra water?

Most need regular watering through their first growing season. Trees and large shrubs often need supplemental watering for longer. Local extension services publish guidance for specific climates and plant types.