blackwood
Acacia melanoxylon · Fabaceae
blackwood (Acacia melanoxylon) is a perennial tree in the Fabaceae family. It is introduced to North America rather than native. USDA records it as hardy in zone 8 and warmer, down to about 14°F.
At a glance
| Type | tree USDA |
|---|---|
| Lifecycle | perennial USDA |
| Native status | introduced USDA |
| Mature height | 40 ft USDA |
| Light | full-sun USDA |
| Water need | medium USDA |
| Growth rate | rapid USDA |
| Soil pH | 6–8.3 USDA |
| Bloom | March–April USDA |
| Flower color | White USDA |
| Hardiness zones | 8 and warmer USDA |
| Guild layer | canopy Derived |
| Nursery availability | No Known Source USDA |
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 needs full sun. USDA rates it as having moderate water needs. Its drought tolerance is rated high. It will not tolerate waterlogged soil — USDA rates its anaerobic tolerance as none. It is recorded on soils from pH 6 to 8.3 — a broad range that spans acidic through mildly alkaline ground. Its cold limit is zone 8.
Size and growth
At maturity it reaches about 40 ft, making it a substantial woody plant. It grows quickly.
Bloom period
USDA records a bloom period of March through April. Flowers are white.
A flowering date, not a pollinator rating.
Foliage, flower and season
Summer foliage is dark green, fine in texture. Its flowers are conspicuous. Its fruit or seed heads are conspicuous, extending interest past flowering. Its active growth period is spring and summer. USDA rates its lifespan as short, so plan on replacing or resowing it rather than treating it as permanent structure.
What the site needs to provide
USDA records it across sites receiving 16 to 40 inches of annual precipitation. It needs at least 180 frost-free days to finish its season. It roots to at least 28 inches. Fertility requirement: low — no feeding needed on ordinary garden soil.
Propagating it
It takes readily from seed, cuttings, bare root and container stock. USDA records no cold-stratification requirement, so seed should germinate without a chilling period. Its seed spreads at a slow rate. It spreads vegetatively at a moderate rate.
Resilience and wildlife
Browsing animals rate it barely palatable — the sourced basis for calling it deer-resistant. Its fire tolerance is rated medium, and it can resprout after damage. Its growth form is recorded as multiple stem.
Role in a guild
Canopy. In a layered planting this is the tallest layer of a planting — it sets the light budget everything beneath it lives on. The layer is derived by a fixed rule from growth habit and mature height.
Tags
Related plants
Others in Acacia
- coastal wattle Acacia cyclops
- koa Acacia koa
- koaoha Acacia koaia
- Sydney golden wattle Acacia longifolia
Similar role and hardiness
- Pacific madrone Arbutus menziesii
- Coulter pine Pinus coulteri
- canyon live oak Quercus chrysolepis
Where this data comes from
Every value on this page comes from the USDA PLANTS database record for symbol ACME, 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, browse palatability, cold stratification, Drought tolerance, fall conspicuous, fertility requirement, fire tolerance, Flower color, flower conspicuous, foliage color, foliage porosity winter, foliage texture, frost free days min, fruit conspicuous, growth form, Growth rate, Hardiness zones, Lifecycle, lifespan, Light, Mature height, Minimum temperature, Native status, Nitrogen fixation, Nursery availability, precipitation max in, precipitation min in, propagation, resprout ability, root depth in, seed spread rate, Soil pH, Soil pH (upper), Tolerance of wet soil, Toxicity, Type, vegetative spread rate, Water need.
- Derived by a fixed rule from those columns: Guild layer.
Read our full data sources and methodology.
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