Annual phlox (Drummond’s phlox) Phlox drummondii
Annual phlox (Drummond’s phlox) (Phlox drummondii) is an annual flowering plant in the Polemoniaceae family, native to Texas, USA. It grows 15–45 cm (6–18 in) tall and 20–30 cm (8–12 in) wide, wants full sun and moderate water, and is hardy to about -2 °C (28 °F). Space plants about 20 cm (8 in) apart.
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Annual phlox (Drummond’s phlox) at a glance
| Type | Annual flowering plant |
|---|---|
| Family | Polemoniaceae |
| Mature height | 15–45 cm (6–18 in) |
| Mature spread | 20–30 cm (8–12 in) |
| Spacing | 20 cm (8 in) centre to centre |
| Sun | Full sun, at least 6 h of direct sun a day |
| Water | Moderate; drought tolerance moderate, waterlogging tolerance none |
| Soil pH | 5.5–7.5 |
| Cold hardiness | About -2 °C (28 °F) once established (roughly USDA zone 9) |
| Heat stress | Likely above about 36 °C (97 °F) |
| Flowering | about 9–11 weeks after planting, for 7–13 weeks |
| Days to maturity | About 100 days from planting |
| Wind tolerance | Low |
| Pollinator value | High |
| Edible | Not grown as food |
| Native to | Texas, USA |
| Common in gardens of | 🇺🇸 United States, 🇬🇧 United Kingdom, 🇮🇪 Ireland, 🇩🇪 Germany, 🇯🇵 Japan, 🇦🇺 Australia, 🇿🇦 South Africa |
Is Annual phlox (Drummond’s phlox) toxic?
- People: not known to be toxic
- Cats: not known to be toxic
- Dogs: not known to be toxic
Not known to be poisonous.
If a child or pet may have eaten part of a plant, call a poison centre or vet straight away.
Companion planting: what to grow with Annual phlox (Drummond’s phlox)
No well-documented helpful pairing. Group it with plants that like full sun and moderate water.
Questions about Annual phlox (Drummond’s phlox)
- How far apart should I plant Annual phlox (Drummond’s phlox)?
- About 20 cm (8 in) apart, centre to centre. A mature plant spreads 20–30 cm (8–12 in).
- Does Annual phlox (Drummond’s phlox) need full sun?
- Full sun: at least 6 hours of direct sun a day.
- How much water does Annual phlox (Drummond’s phlox) need?
- Moderate water. Drought tolerance is moderate and waterlogging tolerance none.
- How cold-hardy is Annual phlox (Drummond’s phlox)?
- It tolerates about -2 °C (28 °F) once established, roughly USDA zone 9. As an annual it is usually planted out after the last frost.
- When does Annual phlox (Drummond’s phlox) flower?
- About 9–11 weeks after planting, for 7–13 weeks.
- Is Annual phlox (Drummond’s phlox) poisonous to cats and dogs?
- For cats it is not known to be toxic; for dogs not known to be toxic; for people not known to be toxic. Not known to be poisonous.
- What grows well with Annual phlox (Drummond’s phlox)?
- There is no well-documented companion pairing for Annual phlox (Drummond’s phlox). Group it with plants that like the same sun (full sun) and water (moderate).
Sources and evidence
Evidence grade A (A: strong evidence).
- Plants of the World Online (taxonomy, native range), Royal Botanic Gardens, Kew
- RHS Find a Plant (plant profiles and growing guides), Royal Horticultural Society
- USDA PLANTS Database, USDA NRCS
Notes and assumptions
- A half-hardy annual in cool climates: sow under glass in spring and plant out after the last frost.
- Named after Thomas Drummond, who sent seed from Texas to Britain in the 1830s. Bright heads of flowers on a low, bushy plant, used in bedding and at the front of a border.
Reference values for planning, not horticultural, veterinary or medical advice. Varieties, soils and local climates differ: check with a local nursery or extension service.
Related plants
- Garden phlox Phlox paniculata
- Moss phlox (creeping phlox) Phlox subulata
- Qantu (sacred flower of the Incas) Cantua buxifolia
- Cup-and-saucer vine (cathedral bells) Cobaea scandens
- Woodland phlox (wild blue phlox) Phlox divaricata
- Creeping Jacob’s ladder (spreading Jacob’s ladder) Polemonium reptans
- Sunflower Helianthus annuus
- French marigold Tagetes patula