Illustration
Photo credits and licenses
Real photographs from naturalists and photographers worldwide, each used under its own license. Credit: Photo by Linda Jo Conn / iNaturalist (CC BY), Photo by Linda Jo Conn / iNaturalist (CC BY), Photo by Joseph Aubert / iNaturalist (CC BY) and Photo by Joseph Aubert / iNaturalist (CC BY). How photos are sourced →
Annual Phlox
Phlox drummondii
Annual Phlox blooms from May through September.
Months here are Northern Hemisphere months; in the Southern Hemisphere, shift them by six months.
Growing Annual Phlox
Plant it in full sun. It prefers moderate water. It is hardy in USDA zones 2–11. Expect it to reach about 12 in tall and 12 in wide at maturity, in roughly 1 year (not yet checked).
No toxicity note is on file for Annual Phlox. That is not a clearance: check its safety for people and pets before planting.
What was checked
Mature height and spread, hardiness zones, sun and the trait tags were checked against named botanical sources for this plant. The bloom months and water need on this page were not, and each fact above says which. The planting, spacing and size sections are derived from these checked facts by a fixed rule, not checked separately, and the plant type is the library's own classification.
When to plant Annual Phlox
Wait until all danger of frost has passed, then plant out Annual Phlox into warm soil; in most zones that means late spring. Planted then, it flowers from May to September.
Month-by-month timing for your zone is on the planting calendar; if you garden near zone 6, the middle of this plant's hardy range, start with zone 6 in April. Derived from the plant's category, zones and bloom months plus typical zone frost dates, not checked separately.
How big does Annual Phlox get?
12 intall5 ft 7 inan adult12 inwideSee Annual Phlox in a garden plan: the planner shows it in 3D beside everything else you add, growing toward this size over the years.
How far apart to plant Annual Phlox
Derived from the mature spread above by a fixed rule, not checked separately: spacing is the spread, center to center.
Space Annual Phlox about 12 in apart, center to center, so each plant has room to reach its full width.
Add Annual Phlox to a garden plan and the planner draws it at its full width, so you see the spacing before you buy.
Where these facts come from
Annual Phlox's height, spread, hardiness zones, sun and trait tags were checked against 10 published sources on July 29, 2026. Each one is linked below with every fact it carried, which can include a fact this page still marks as not yet checked, because a source carrying a value is not the same as the value being held to the standard. Facts not in that list, and the planting, spacing and size sections, are not covered by these sources.
- Missouri Botanical Gardenheight, spread, hardiness zones, sun and trait tags
- NC State ExtensionPlant Toolboxheight, spread, hardiness zones, sun and trait tags
- everwilde.comEverwilde Farmsheight, hardiness zones, sun and trait tags
- RHSRoyal Horticultural Societyheight, spread, sun and trait tags
- bbbseed.comBBB Seedheight, hardiness zones and sun
- Clemson Home and Garden Information CenterClemson Cooperative Extension HGICheight, sun and trait tags
- Lady Bird Johnson Wildflower Centerheight, sun and trait tags
- Outsideprideheight, hardiness zones and trait tags
- vermontwildflowerfarm.comVermont Wildflower Farmheight, hardiness zones and sun
- US Forest ServicePlant of the Weekheight and trait tags
How the checking works, and what each standard covers, is on the verified plants page.
Comes in 5 varieties across 4 colors
Same plant, same care - pick the color you are growing.
Compare every variety in the Annual Phlox group
Every figure is the variety's own page fact. Tap a name to open it.
| Variety | Color | Blooms | Hardiness | Sun | Size (H × W) |
|---|---|---|---|---|---|
| Annualthis page | Pink | May–Sep | Zones 2–11 | Full sun | 12 in × 12 in |
| Lavender | Purple | May–Sep | Zones 2–11 | Full sun | 12 in × 12 in |
| Peach | Orange | May–Sep | Zones 2–11 | Full sun | 12 in × 12 in |
| Purple | Purple | May–Sep | Zones 2–11 | Full sun | 12 in × 12 in |
| Red | Red | May–Sep | Zones 2–11 | Full sun | 12 in × 12 in |
| White | White | May–Sep | Zones 2–11 | Full sun | 12 in × 12 in |
Good to know about Annual Phlox
Curated from university extensions, botanic gardens and other primary sources, with the source named on every note. A note reports what its source says; where that differs from a fact above, the fact above is this entry's stored value, and its mark says whether it has been checked.
Worth knowing
A true Texas wildflower (Pride of Texas), named for Thomas Drummond, the Scottish botanist who collected it in Texas in the 1830s. per USDA
When it blooms
A cool-season bloomer whose window slides with climate: one source gives April to June, another May to July. The heaviest show is spring to early summer. per North Carolina and Missouri Botanical
Pinch for a bushier plant
Pinch the main stems of young plants to drive branching for a fuller, bushier plant with more flower heads. It is short, so it needs no staking. per Illinois and Missouri Botanical
Powdery mildew, the main disease
Its signature disease is powdery mildew, a grayish-white leaf coating worst in crowding, shade and humidity. Give plants room, water at the base, and clear diseased debris. per Clemson and Iowa State
Self-seeds readily
It reseeds itself easily in good conditions, so a planting can return from self-sown seed. Deadhead spent flowers to keep volunteers down where you do not want them. per Clemson and North Carolina
Draws bees, butterflies, hummingbirds
Fragrant, nectar-rich flowers draw bees, butterflies and hummingbirds. In the wild, though, it is pollinated almost exclusively by the pipevine swallowtail butterfly. per North Carolina
What pairs well with Annual Phlox
Good companions share its growing conditions and add something it lacks: an earlier or later bloom, a lower carpet in front, or structure through winter.
Perennial Sunflower
Shares full sun and moderate water; overlaps, then carries the display into mid fall; both are strong pollinator plants; its seed heads stand through winter, for structure and the birds.
Aster
Shares full sun and moderate water; overlaps, then carries the display into mid fall; both are strong pollinator plants; its seed heads stand through winter, for structure and the birds.
Winterberry
Shares full sun and moderate to high water; blooms in mid fall as this one finishes; both are strong pollinator plants, and they feed in different months; stands well above at 6.5 ft, a canopy to plant beneath.
Joe Pye Weed
Shares full sun and moderate to high water; both are strong pollinator plants; its seed heads stand through winter, for structure and the birds; taller at 6 ft, for the layer behind it.
Hyacinth
Shares full sun and moderate water; blooms in early spring, before this one opens; both offer pollinator forage, in different months; lower at 10 in, for the front of the border.
Windflower
Takes full sun to part sun and moderate water; blooms in early spring, before this one opens; both are strong pollinator plants, and they feed in different months; lower at 6 in, for the front of the border.
Rosemary
Shares full sun and low to moderate water; opens in early spring and overlaps into this one's season; both are strong pollinator plants; evergreen, so the bed keeps its shape through winter.
Switchgrass
Shares full sun and low to moderate water; overlaps, then carries the display into mid fall; both are strong pollinator plants; its seed heads stand through winter, for structure and the birds.
Explore similar plants
You might also like
Design a garden with this
Drop this plant onto a 3D plan, see how it fills in, and watch your whole garden bloom across the year.