How to design a flower garden

1. Read the site before you pick a single plant

Every good flower bed design starts with the spot, not the plant catalogue. Watch the area for a full day and note:

• Sun exposure. Full sun means 6 or more hours of direct sun. Part shade is roughly 3 to 6 hours. Full shade is less than 3.
• Moisture and drainage. Does water pool after rain, or does the soil dry out within a day?
• Soil. Squeeze a handful of damp soil. Sticky clay, gritty sand or crumbly loam changes what will thrive.
• Viewing angle. Where will you see the garden from most: the kitchen window, the patio, the street?

Eden asked the same questions in its plant search. Filtering by sun exposure and moisture first removes the plants that would struggle before you fall in love with them. Shady yards even got their own plant pack, Suburban Shade.

2. Confirm your hardiness zone

Your hardiness zone tells you which perennials survive your winter. A plant rated for zones 4 to 8 will come back every year in zone 5 but may rot or skip dormancy in zone 10. Annuals ignore zones because they finish in one season, which makes them useful for filling gaps.

Eden could detect a North American hardiness zone automatically with GPS and flag plants that would not do well locally. Without the app, look up your zone on your national plant hardiness map, then treat the zone range on every plant label as a hard filter.

3. Choose the bed shape and size

• Depth: aim for at least 1.2 m (4 ft) from front to back. Beds narrower than that can only hold one or two rows and read as a thin strip.
• Island beds are seen from all sides, so tall plants go in the middle, not the back.
• Border beds run along a fence, wall or house, so tall plants go at the back.
• Beds under the eaves take the roof's drip line, and in snowy climates they also take falling icicles and meltwater. If ice builds up along your eaves every winter, the cause is usually heat escaping through the attic, which this attic guide on insulation, ventilation and ice dams explains. Keep delicate perennials about 60 cm (2 ft) out from the drip line.
• Curves soften a rectangular yard. Lay a garden hose on the lawn to test the outline before cutting the edge.

In Eden you set the plantable area by placing Adam and Eve at diagonal corners of the bed. Outlining the real bed with a hose does the same job in the yard.

4. Layer plants by height

Height layering is what makes a flower garden look designed rather than scattered. Use three tiers:

Break the rule now and then. A few airy, see-through tall plants near the front add depth without blocking the view.

5. Pick a color scheme

Two or three main colors plus foliage green is plenty. Common schemes that work:

• Harmonious: neighboring colors, like purple, blue and pink. Calm and cohesive.
• Complementary: opposites, like purple with yellow or blue with orange. Bold and lively.
• Single color: an all-white bed with calla lily and snow-in-summer glows at dusk.

Eden's plant library let you search by color, which is the fastest way to test a scheme before buying.

6. Plan bloom succession from spring to fall

Most perennials bloom for only a few weeks. A bed planted entirely with June bloomers looks spectacular for a month and green for the rest of the year. Choose plants from each season:

This is why Eden added a blooming season view in version 1.2: seeing the same garden in spring, summer and fall shows the gaps before you plant.

7. Plant in groups and repeat

• Plant in odd-numbered groups of 3, 5 or 7. Single plants look lost; drifts look intentional.
• Repeat one or two key plants along the length of the bed to tie it together.
• Space by mature width, not pot size. Crowding causes mildew; gaps can be filled with annuals for the first year.

8. Make the plant list and prepare the soil

Once the layout is settled, write a plant list with quantities for every group. Eden generated this list automatically so you could take it to the nursery. Before planting, clear weeds and grass, loosen the soil to a spade's depth and work in compost. Water new plants deeply and mulch around them to hold moisture.

Common flower garden design mistakes

• Buying plants first and finding a spot later.
• Ignoring the zone range on the label.
• One of everything instead of groups.
• A bed too narrow to layer.
• Everything blooming in the same month.

Try the layout before you dig

Sketching on paper works, and so does photographing the bed and marking plant positions on the photo. That idea, planting virtual flowers on a real picture of your yard, is exactly what Eden Garden Designer was made for, and a revamped version of the app is in the works.