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Plant Details

Hybrid Pine

Pinus x attenuradiata 'Monty Knob'

Also called: Attenuradiata Pine

Monty Knob is a hardy and vigorous hybrid pine that combines the best of its parents: the resilience of the Knobcone Pine (Pinus attenuata) and the rapid growth of the Monterey Pine (Pinus radiata). This evergreen conifer is particularly valued for interior or garden plantings where a more stable, smaller alternative to the standard Monterey Pine is desired. It features attractive green-gray foliage and a conical crown that remains dense when young, eventually maturing into a more open and rounded form. This selection is known for being faster than a straight Knobcone Pine but more adaptable to garden conditions than a Monterey Pine.

Winter interestSalt tolerantHeat tolerantCold tolerantFragrantDeer resistantClay tolerantBeginner friendlyDrought tolerant
Pinus x attenuradiata 'Monty Knob' illustration
No image available

Plant Snapshot

TypeTree | Woody | Perennial | Evergreen
Growth habitUpright
Use categoriesOrnamental
SettingOutdoor
Growth rateFast
Mature size classLarge
Bloom colorNot listed yet.
Bloom seasonNot listed yet.
HardinessZones 7a-9b
Size360-480 in tall | 240-360 in wide
Life expectancy80 years
Size noteTypically reaches 30-40 feet in height in a garden setting, much smaller than its parent species in the wild.
Spacing240-360 in apart
Spacing noteBest planted with enough space to allow for its 20-30 foot spread at maturity.

Growth Conditions

LightFull Sun
WaterLow
SoilClay | Loamy | Rocky | Sandy
DrainageWell-Drained
Leaf notesGreen-gray needles, typically in bundles of three.
Pruning noteRequires minimal pruning; remove dead or diseased wood in late winter or early spring before new growth starts.
Feeding noteGenerally does not require supplemental fertilizer; can benefit from a balanced slow-release formula in early spring if soil is extremely poor.
Propagation noteUsually propagated by seed; cones may require heat to release seeds, a trait inherited from the Knobcone parent.

Seasonal Timing

Feeding window

Early spring

Optional fertilization for young trees in poor soil.

Pruning window

Late winter

Prune for health and structure before spring growth begins.

Cautions

Pests

Dwarf Mistletoe

Can be a host for Arceuthobium species.

Pine Pitch Canker

Vulnerability varies; hybrids often show improved resistance compared to P. radiata.

Pet safetyLow toxicity; pine needles can be a choking hazard or cause mild GI upset if ingested.
Allergy noteProduces wind-borne pollen which can be an allergen for sensitive individuals.
Health noteResins and sawdust may cause skin irritation (dermatitis) in some people.

Sources

Places that sell it

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