violet tree
Polygala cowellii · Polygalaceae
violet tree (Polygala cowellii) is a perennial tree in the Polygalaceae family. It is native to North America. USDA records it as hardy in zone 11 and warmer, down to about 40°F.
At a glance
| Type | tree USDA |
|---|---|
| Lifecycle | perennial USDA |
| Native status | native USDA |
| Mature height | 33 ft USDA |
| Growth rate | slow USDA |
| Soil pH | 5–7.5 USDA |
| Bloom | March–May USDA |
| Flower color | Purple USDA |
| Hardiness zones | 11 and warmer USDA |
| Guild layer | understory Derived |
USDA quoted from the USDA PLANTS database · Derived computed by a fixed rule from those columns. No value on this page is estimated.
Growing conditions
It is recorded on soils from pH 5 to 7.5 — a broad range that spans acidic through mildly alkaline ground. Its cold limit is zone 11.
Size and growth
At maturity it reaches about 33 ft, making it a substantial woody plant. It grows slowly.
Bloom period
USDA records a bloom period of March through May. Flowers are purple.
A flowering date, not a pollinator rating.
Foliage, flower and season
Summer foliage is yellow-green, medium in texture. Its flowers are conspicuous. Its fruit or seed heads are conspicuous, extending interest past flowering. Its active growth period is fall.
What the site needs to provide
USDA records it across sites receiving 35 to 90 inches of annual precipitation. It needs at least 365 frost-free days to finish its season. It roots to at least 36 inches. Fertility requirement: medium.
Propagating it
Seed is the only propagation method USDA lists. Division and cuttings are not listed as options. USDA records no cold-stratification requirement, so seed should germinate without a chilling period.
Resilience and wildlife
Its fire tolerance is rated medium.
Role in a guild
Understory. In a layered planting this is the layer beneath the canopy, tall enough to hold structure but shaded from above. The layer is derived by a fixed rule from growth habit and mature height.
Tags
Related plants
Similar role and hardiness
- custard apple Annona reticulata
- wild cinnamon Canella winterana
- Chamisso's manfern Cibotium chamissoi
- hapu'u Cibotium glaucum
- tietongue Coccoloba diversifolia
Where this data comes from
Every value on this page comes from the USDA PLANTS database record for symbol POCO5, or is computed from those values by a fixed rule. Nothing here is estimated or model-generated. Where USDA publishes no value, this page omits the claim rather than filling the gap.
- Quoted from USDA PLANTS: active growth period, Bloom, Bloom end, cold stratification, fall conspicuous, fertility requirement, fire tolerance, Flower color, flower conspicuous, foliage color, foliage porosity winter, foliage texture, frost free days min, fruit conspicuous, Growth rate, Hardiness zones, Lifecycle, Mature height, Minimum temperature, Native status, Nitrogen fixation, precipitation max in, precipitation min in, propagation, resprout ability, root depth in, Soil pH, Soil pH (upper), Type.
- Derived by a fixed rule from those columns: Guild layer.
Read our full data sources and methodology.
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