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PeeGee Hydrangea
Hydrangea paniculata 'Grandiflora'
Also called panicle hydrangea and pee gee hydrangea
PeeGee Hydrangea blooms from July through September.
Months here are Northern Hemisphere months; in the Southern Hemisphere, shift them by six months.
Growing PeeGee Hydrangea
Plant it in full sun. It prefers moderate water. It is hardy in USDA zones 3–8. Expect it to reach about 11 ft tall and 10 ft wide at maturity, in roughly 4 years (a house reading).
What was checked
Mature height and spread, hardiness zones, sun, water, bloom months and color and the trait tags were checked against named botanical sources for this plant, with what the sources could not settle written down; years to mature size rests on a recorded house rule where no publisher states one, and is marked so; its common name and alternate names have not been checked yet. Each fact above carries its own mark. The planting, spacing and size sections are derived from these checked facts by a fixed rule, not checked separately, and the plant type is the library's own classification.
When to plant PeeGee Hydrangea
Plant PeeGee Hydrangea in early spring as soon as the soil is workable, or in early fall at least six weeks before your first frost, so roots establish in cool weather. In zone 5, the middle of its hardy zones 3 to 8, spring means April to June and fall means August or September. Once settled, it blooms from July to September.
Month-by-month timing for your zone is on the planting calendar; if you garden near zone 5, the middle of this plant's hardy range, start with zone 5 in April. Derived from the plant's category, zones and bloom months plus typical zone frost dates, not checked separately.
How big does PeeGee Hydrangea get?
11 fttall5 ft 7 inan adult10 ftwideSee PeeGee Hydrangea in a garden plan: the planner shows it in 3D beside everything else you add, growing toward this size over the years.
How far apart to plant PeeGee Hydrangea
Derived from the mature spread above by a fixed rule, not checked separately: spacing is the spread, center to center.
Give PeeGee Hydrangea about 10 ft of clear ground in every direction, measured from its center. It is one plant with room around it, not a row, and a raised bed is too small for it.
Add PeeGee Hydrangea to a garden plan and the planner draws it at its full width, so you see the spacing before you buy.
Where these facts come from
PeeGee Hydrangea's height, spread, hardiness zones, sun, water, bloom months and color, trait tags, soil, diseases, pests and toxicity were checked against 8 published sources on August 19, 2026. Each one is linked below with every fact it carried, which can include a fact this page still marks as not yet checked, because a source carrying a value is not the same as the value being held to the standard. Facts not in that list, and the planting, spacing and size sections, are not covered by these sources.
- Missouri Botanical GardenPlant Finderheight, spread, hardiness zones, sun, water, bloom months and color, trait tags, soil, diseases and pests
- NC State ExtensionGardener Plant Toolboxheight, spread, hardiness zones, sun, bloom months and color, trait tags, soil, diseases and pests
- RHSRoyal Horticultural Societyheight, spread, water, bloom months and color, trait tags, soil, diseases, pests and toxicity
- Chicago Botanic GardenPlant Finderheight, hardiness zones, sun, bloom months and color and soil
- The Morton ArboretumLisle, Illinois, zone 5height, spread, hardiness zones, water, soil and diseases
- plantdatabase.uconn.eduUConn Plant Database (Mark H. Brand, University of Connecticut)sun, bloom months and color, trait tags and pests
- ASPCAAnimal Poison Controltoxicity
- Chicago Botanic GardenComparative Trials of Hydrangea paniculata Cultivarstrait tags
How the checking works, and what each standard covers, is on the verified plants page.
Good to know about PeeGee Hydrangea
Curated from university extensions, botanic gardens and other primary sources, with the source named on every note.
Safety
Toxic to dogs, cats and horses; the leaves and buds hold a cyanogenic glycoside. Eating it mostly causes vomiting and diarrhea. per ASPCA
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Design a garden with this
Drop this plant onto a 3D plan, see how it fills in, and watch your whole garden bloom across the year.