California Buckeye

Aesculus californica

Sapindaceae, Hippocastanaceae · broadleaf deciduous tree · introduced

Last updated March 9, 2026

Plant Profile

Height

12–30 ft

Spread

32 ft

Growth Rate

Moderate

Size at 20 yr

25 ft

Lifespan

Long-lived

Light

Sun to Part Shade

Soil Drainage

Well Drained

Soil pH

5.5-7.5

Water

Moderate

Drought Tolerance

High

Hardiness

Zones 7a–8b

Bloom Time

February to March

Origin

California

Active Conidial Spread

View full calendar (8 stages)

Stage	Typical Window	What to Look For
Bud break BBCH 07	Feb 15-Mar 15	Buds swelling and beginning to open; first green tissue visible
Leaf emergence BBCH 11	Mar 1-Apr 1	First leaves fully unfurled on new growth
Bloom start BBCH 61	Jun 15-Aug 15	First open flowers visible; flowers white
Bloom end / petal fall BBCH 69	Jul 15-Aug 31	Last petals falling; flower structures fading
Fruit/seed development BBCH 71	Jun 1-Aug 31	Fruit or seed structures forming; fruit color: brown
Fruit/seed maturity BBCH 85	Sep 1-Nov 30	Fruit fully colored and ripened; seed dispersal may begin
Fall color / leaf senescence BBCH 93	Oct 1-Nov 15	Leaves changing color; fall display beginning
Dormancy BBCH 97	Nov 15-Feb 28	Leafless; no active growth; dormant buds set

Data Maturity

Structured Multiple sources. Expert review underway.