False sunflower
Heliopsis helianthoides · Asteraceae
Golden-yellow daisies, single or double, from June to September on a bushy, upright plant. It flowers longer than any true sunflower.
- Size
- 4 ft tall, 2½ ft wide
- Zones
- 3 to 9
- Light
- Full sun
- Flowers
- Late June to early September
- Pets
- No toxicity recorded
- Job in a bed
- Drift
A bed built around false sunflower
The planner designed this bed around false sunflower when this page was made: a 12 × 6 ft (3.7 × 1.8 m) cottage garden in zone 6, full sun. It chose the other plants from the 966 that suit those conditions, and says below why false sunflower stands where it does.
The plants
- 1 False sunflower × 4, yellow
- 2 Sea thrift × 12, pink
- 3 Creeping phlox 'Candy Stripe' × 3, pink
- 4 Little bluestem 'The Blues' × 3, tan
- 5 Globe arborvitae 'Danica' × 1, green leaves
- 6 Coneflower 'White Swan' × 3, white
- 7 Hyacinth 'Delft Blue' × 12, blue
- 8 Ornamental onion 'Purple Sensation' × 5, purple
Why this plant
- The only yellow. The one hot colour: every other flower here is cool or neutral.
Why here
- Anchors a back corner. At 4 ft it is the tallest plant here, and the tallest close the ends of the bed, where they stand in front of nothing.
- A step in the back row. Next to little bluestem 'The Blues' (3 ft) and coneflower 'White Swan' (2½ ft): no two neighbours there are the same height, so the back steps up and down like a skyline.
- 4 plants in 2 groups (3 and 1). Seen again further along, the same plant ties the bed together.
Why now
- In flower for 11 weeks. From late June to early September.
- Fills a gap. For one of those weeks nothing else on the plan is in flower.
Planned as a cottage garden: 26 of the 26 plants (100%), bulbs aside, stand alone or in groups of no more than five, small enough for the kinds to mingle. The flowering is at its height from early August, with 3 kinds out together. Neither end outweighs the other: the visual weight is split 48 to 52, left to right.
The planner's own design check: 12 Excellent, 5 Good. It flags one thing to watch: Nothing on this plan is highly poisonous or an aggressive spreader.
Open this bed in the planner Change its size, the sun or the style, move plants about, or swap one for another.
Where false sunflower goes in a border
At 4 ft it belongs at the back of a bed. In the planner's ten height classes it is moderately tall (3 to 4 ft).
Its job: drift. Planted in a small group of three or five, and repeated further along in the other number.
It starts a month before black-eyed Susan and keeps going, so it is the yellow to rely on in July. Strong gold wants purple and blue beside it: bee balm, blazing star, Russian sage.
- Long-flowering yellow for the middle of a border
- Cut flowers
- Prairie planting
What to plant with false sunflower
Plants recorded as good partners for it, and what each pairing does:
- Wild bergamot: in flower together for eight weeks, from early July.
- Blazing star: purple against yellow, opposite each other on the colour wheel, in flower together for six weeks.
- Russian sage: in flower together for nine weeks, from mid July.
Questions about false sunflower
Does false sunflower need sun or shade?
False sunflower grows in full sun (6 or more hours of direct sun a day).
It wants ordinary well-drained soil, of average fertility, and a good soak in dry spells. Once settled in, it stands drought.
What zones does false sunflower grow in?
USDA zones 3 to 9. It is hardy to zone 3, which means it survives winter nights down to about −30 °F (−34 °C).
Gardening in Canada? Use the USDA zone for your town: Canada's own zone map uses different numbers.
When does false sunflower flower in my zone?
In zone 5 it flowers late June to early September. As a summer flower it moves about half a week for every zone: earlier where it is warmer.
| Zone 3 | Early July to early September |
|---|---|
| Zone 4 | Early July to early September |
| Zone 5 | Late June to early September |
| Zone 6 | Late June to early September |
| Zone 7 | Late June to early September |
| Zone 8 | Late June to early September |
| Zone 9 | Mid June to early September |
Worked out from Hopkins' bioclimatic law: spring arrives about four days later for each degree of latitude north, and one zone is roughly two degrees. A warm spring or a cold one moves any garden two weeks either way.
How far apart should false sunflower be planted?
24 in (60 cm) apart, from the middle of one plant to the middle of the next. That is a little closer than its full width of 2½ ft (75 cm), so a group knits into one patch.
It grows 4 ft (120 cm) tall. Give it the full distance from anything taller, or it will lean out towards the light.
How many false sunflower plants do I need?
At 24 in apart, set out in staggered rows:
- 3 to fill 10 square feet (about 1 m²)
- 6 for a single row 10 ft (3 m) long
- 10 to fill a 4 × 8 ft bed on its own
In a mixed border, plant it as a group of three or five, with a second group further along in the other number.
In the bed above, the planner used four in two groups.
Is false sunflower poisonous to dogs and cats?
No toxicity is recorded for dogs, cats, horses or people, according to NC State Extension.
"Not toxic" is not "edible": a pet that eats a lot of any plant can be sick.
Do deer eat false sunflower?
Mostly not. NC State lists it as resistant to deer and rabbits. No plant is proof against a hungry deer in a hard winter, but this one is low on the menu.
Will false sunflower spread?
It seeds itself about; the risk of it taking over is moderate. Self-seeds freely. Remove the spent flowers to limit seedlings.
What flowers after false sunflower?
False sunflower is over by early September. These start as it finishes and carry the same spot on, so it never goes flat:
- Garden chrysanthemum: from mid September to late October, 24 in tall, to stand in front of it and cover its fading stems.
- Montauk daisy: from mid September to late October, 3 ft tall, to stand in front of it and cover its fading stems.
- New York aster: from late August to mid October, 3 ft tall, to stand in front of it and cover its fading stems.
What does false sunflower look like in winter?
False sunflower dies down, but leave the stems standing: the seed heads stand through the winter, and songbirds eat the seed. Cut them down in early spring, before the new shoots come.
Is false sunflower good for bees and butterflies?
False sunflower is visited by pollinators, butterflies, hummingbirds and songbirds.
It is native to the United States and Canada.
More Heliopsis
- False sunflower 'Summer Nights' Heliopsis helianthoides var. scabra 'Summer Nights'
- False sunflower 'Summer Sun' Heliopsis helianthoides var. scabra 'Sommersonne'
In these guides
- Plants for slopes and banks
- Deer-resistant perennials for full sun
- Rabbit-resistant plants
- Drought-tolerant perennials for full sun
- Pet-safe plants for a sunny border
- Native perennials for pollinators
- Garden plants native to Canada
- Plants for hummingbirds
- Plants for butterflies
- Plants that feed garden birds
- Tall perennials and grasses for the back of a border
Zone guides: Zone 3 · Zone 4 · Zone 5 · Zone 6 · Zone 7 · Zone 8 · Zone 9
Every fact on record
- Type
- Perennial
- Size
- 4 ft (120 cm) tall, 2½ ft (75 cm) wide
- Plant
- 24 in (60 cm) apart
- Height class
- Moderately tall (3 to 4 ft)
- Place in the bed
- Back
- Flowers
- Late June to early September; daisies; yellow
- Leaves
- Medium texture, herbaceous; green
- Shape
- Upright, self-seeding
- Hardy in
- USDA zones 3 to 9
- Light
- Full sun
- Soil
- Average, well-drained
- Water
- Moderate
- Feeding
- Light, in spring
- Family
- Asteraceae
- Comes from
- SE Canada, and the North Central and Eastern United States
- Attracts
- Pollinators, butterflies, hummingbirds, songbirds
- Stands up to
- Deer, rabbits, drought, heat, poor soil, erosion
Checked against NC State Extension and VASCAN (plants of Canada). Flowering times are for zone 5: later in colder zones, earlier in warmer ones. Toxicity and spread information is a general gardening guide, not veterinary or medical advice, and invasive status varies by region. If a person or pet eats a plant, contact poison control or a vet. Check your local invasive species list before planting anything with a spread warning.