# Rosebay Rhododendron (Rhododendron maximum)

> The great evergreen rhododendron of Appalachian stream valleys, with pink-white trusses in July.

Also called great laurel, great rhododendron. Category: Native Shrubs. Grown from seed by Blue Whale Trees. Web version: https://bluewhaletrees.com/plants/rosebay-rhododendron/

![Rosebay rhododendron (Rhododendron maximum) large evergreen leaves around a bud](https://bluewhaletrees.com/img/plants/rosebay-rhododendron-h1610-800.jpg)
*Photo: Syrio, CC BY-SA 4.0, cropped · [Wikimedia Commons](https://commons.wikimedia.org/wiki/File:Rhododendron_maximum_05.jpg)*

## Facts

- Type: Shrub
- Mature height: 10 to 15 ft
- USDA hardiness zones: 3 to 7
- Grows wild in: The Appalachians, stream banks and the forest understory
- Native range: 20 states and [the District of Columbia](https://bluewhaletrees.com/tools/native/index.html.md?state=DC), north to [Maine](https://bluewhaletrees.com/tools/native/index.html.md?state=ME), south to [Georgia](https://bluewhaletrees.com/tools/native/index.html.md?state=GA) and west to [Alabama](https://bluewhaletrees.com/tools/native/index.html.md?state=AL) ([Alabama](https://bluewhaletrees.com/tools/native/index.html.md?state=AL), [Connecticut](https://bluewhaletrees.com/tools/native/index.html.md?state=CT), [Delaware](https://bluewhaletrees.com/tools/native/index.html.md?state=DE), [Georgia](https://bluewhaletrees.com/tools/native/index.html.md?state=GA), [Kentucky](https://bluewhaletrees.com/tools/native/index.html.md?state=KY), [Maine](https://bluewhaletrees.com/tools/native/index.html.md?state=ME), [Maryland](https://bluewhaletrees.com/tools/native/index.html.md?state=MD), [Massachusetts](https://bluewhaletrees.com/tools/native/index.html.md?state=MA), [New Hampshire](https://bluewhaletrees.com/tools/native/index.html.md?state=NH), [New Jersey](https://bluewhaletrees.com/tools/native/index.html.md?state=NJ), [New York](https://bluewhaletrees.com/tools/native/index.html.md?state=NY), [North Carolina](https://bluewhaletrees.com/tools/native/index.html.md?state=NC), [Ohio](https://bluewhaletrees.com/tools/native/index.html.md?state=OH), [Pennsylvania](https://bluewhaletrees.com/tools/native/index.html.md?state=PA), [Rhode Island](https://bluewhaletrees.com/tools/native/index.html.md?state=RI), [South Carolina](https://bluewhaletrees.com/tools/native/index.html.md?state=SC), [Tennessee](https://bluewhaletrees.com/tools/native/index.html.md?state=TN), [Vermont](https://bluewhaletrees.com/tools/native/index.html.md?state=VT), [Virginia](https://bluewhaletrees.com/tools/native/index.html.md?state=VA), [West Virginia](https://bluewhaletrees.com/tools/native/index.html.md?state=WV) and [the District of Columbia](https://bluewhaletrees.com/tools/native/index.html.md?state=DC))
- Sun: Shade, Part
- Soil moisture: Average, Wet
- Growth rate: Slow
- Flowers: June to August
- Fruit: Capsules, September to October
- First crop: 3 to 6 years (first flowers)
- Mature spread: 12 ft
- Traits: Evergreen, Showy flowers, Tolerates shade, Wildlife value, Winter interest
- Sold as: Saplings, Seed

Heights and zones are typical ranges for the species in cultivation; local conditions and seed source shift them.

## Availability

Saplings ship [in a pot](https://bluewhaletrees.com/articles/a-sapling-in-a-pot/index.html.md), [usually 12 to 18 inches tall](https://bluewhaletrees.com/articles/small-sapling-or-big-transplant/index.html.md), in the dormant season, and their [height and age](https://bluewhaletrees.com/articles/reading-a-nursery-listing/index.html.md) are stated with the price, once available. Live plants ship February to May and October to November. Not priced yet: leave an email on the web page for one email when it is priced, with a code for 10% off the plants in that order, not shipping or tax, or write to captain@bluewhaletrees.com.

## Notes

Rosebay forms the impenetrable evergreen thickets of the southern mountains and is hardy to zone 3. Given what it wants it becomes a 12-foot evergreen wall that blooms in midsummer. Every part is toxic, yet deer browse it in fall and winter. Belongs on the north side of a house or along a wooded stream.

## Size, growth and what to expect

Expect about a foot of new height a year from a young rosebay rhododendron on an average site, the figure our growth estimator uses for a slow grower. In a garden it stands 10 to 15 feet and spreads 5 to 12 feet, while wild thickets in the southern mountains run 10 to 23 feet tall. The oldest stem dated by its rings was 120 years old.

Trusses of pink to white flowers about 2 inches across open from late May in the south to August in the north, and only twigs in full sunlight flower. Each capsule holds about 400 seeds, and a single stem can live 100 years. Deer browse it in fall and winter, grouse and turkeys eat the buds, and the thickets shelter deer, bears and rabbits through the winter. Great laurel is its other common name, and the genus name means rose tree in Greek. The capsules ripen in September and October and shed their seed in November.

It grows wild from Nova Scotia and Ontario south to Georgia and Alabama, most commonly in the eastern mountains, from sea level to 6,000 feet.

## How to grow Rosebay Rhododendron

Rosebay rhododendron needs shade, shelter and acid soil. Put it under trees or on the north side of a building, out of winter wind and afternoon sun, in ground that stays moist but drains; it rots in stagnant mud. Space plants 8 feet apart and 6 feet off a foundation.

Saplings ship potted. Plant while dormant, in early spring or fall. Set the root ball in a hole three times as wide and slightly shallower, with the root mass a touch above grade, and use native soil only. If your soil is neutral or limey, choose another plant rather than amending. Mulch with pine needles, kept off the stems. Seed is dust-fine and needs light as soon as it is wet. Sow it on the surface of moist peat mix in winter, uncovered, at room temperature under lights and a clear cover. Seedlings come up in about three weeks.

The shallow roots dry out fast, so water weekly through the first two summers. Deer browse it in fall and winter, and rabbits eat the bark and buds, so cage young plants where either is common. Voles tunnel under deep mulch, so keep it to two inches. Prune only to remove dead wood.

Rosebay rhododendron carries both male and female parts in each flower, and bees carry the pollen. A lone shrub can set seed with its own pollen, but a second shrub from a different parent sets more. Growth is slow and the plant is long-lived. Leaves that curl and droop on cold mornings are normal. Yellow leaves with green veins mean the soil is not acid enough. Never dig around the roots. Every part of the plant is toxic if eaten.

## Sources

- [USDA Fire Effects Information System: Rhododendron maximum](https://www.fs.usda.gov/database/feis/plants/shrub/rhomax/all.html)
- [NC State Extension Gardener Plant Toolbox: Rhododendron maximum](https://plants.ces.ncsu.edu/plants/rhododendron-maximum/)
- [Missouri Botanical Garden Plant Finder: Rhododendron maximum](https://plantfinder.mobot.org/PlantFinderDetails.aspx?taxonid=279985)
- [Virginia Tech Dendrology: great rhododendron, Rhododendron maximum](https://dendro.cnre.vt.edu/dendrology/syllabus/factsheet.cfm?ID=81)
- [Lady Bird Johnson Wildflower Center: Rhododendron maximum](https://www.wildflower.org/plants/result.php?id_plant=RHMA4)
- [USDA Forest Service, Woody Plant Seed Manual (2008), Rhododendron chapter](https://www.fs.usda.gov/nsl/Wpsm/Rhododendron.pdf)
- [Go Botany (Native Plant Trust): Rhododendron maximum, great rosebay](https://gobotany.nativeplanttrust.org/species/rhododendron/maximum/)
- [Flora of North America, vol. 8: Rhododendron maximum](http://www.efloras.org/florataxon.aspx?flora_id=1&taxon_id=250065640)
- [USDA Forest Service, Seeds of Woody Plants in the United States, Agriculture Handbook 450 (1974), Rhododendron chapter, Olson](https://archive.org/details/seedsofwoodyplan00fore)
- [Donald W. Hyatt: Raising Rhododendrons and Azaleas from Seed](http://www.tjhsst.edu/~dhyatt/seeds.html)
- [Journal American Rhododendron Society: Roberts 1990, Rhododendrons from Seed: A Novice's Perspective, JARS 44(4)](https://archive.rhododendron.org/v44n4/v44n4-roberts.html)
- [Journal of the Torrey Botanical Society: Elliott and Vose 2012, Journal of the Torrey Botanical Society 139:149-166](https://doi.org/10.3159/TORREY-D-11-00076.1)

## Read before planting

- [Ten planting mistakes that quietly kill trees](https://bluewhaletrees.com/articles/ten-planting-mistakes/index.html.md)
- [Transplanting young trees: timing, water and protection](https://bluewhaletrees.com/articles/transplanting-young-trees/index.html.md)
- [Protecting young trees from voles, rabbits, deer and squirrels](https://bluewhaletrees.com/articles/protecting-trees-from-animals/index.html.md)
- [Native trees for the Southern Appalachians: the valleys, the slopes and the high ridges](https://bluewhaletrees.com/articles/native-trees-for-the-southern-appalachians/index.html.md)
- [Native trees and shrubs for bees: pollen, nectar, nesting and a bloom calendar from willow to witch hazel](https://bluewhaletrees.com/articles/native-trees-for-bees/index.html.md)
- [The habitat around a tree is part of the tree](https://bluewhaletrees.com/articles/habitat-around-a-tree/index.html.md)

## Related

- We grow 21 other rhododendrons and azaleas (Rhododendron): [all of them](https://bluewhaletrees.com/shop/index.html.md?q=rhododendron)
- Plants that share its sun and soil: [Canada Yew](https://bluewhaletrees.com/plants/canada-yew/index.html.md), [Squashberry](https://bluewhaletrees.com/plants/squashberry/index.html.md), [Hobblebush](https://bluewhaletrees.com/plants/hobblebush/index.html.md) and [Mountain Doghobble](https://bluewhaletrees.com/plants/mountain-doghobble/index.html.md)
- Trees to plant it under: [Eastern Hemlock](https://bluewhaletrees.com/plants/eastern-hemlock/index.html.md), [Yellow Birch](https://bluewhaletrees.com/plants/yellow-birch/index.html.md) and [Yellow Buckeye](https://bluewhaletrees.com/plants/yellow-buckeye/index.html.md)
- Same size, similar character: [Catawba Rhododendron](https://bluewhaletrees.com/plants/catawba-rhododendron/index.html.md), [Pinkshell Azalea](https://bluewhaletrees.com/plants/pinkshell-azalea/index.html.md), [Rhodora](https://bluewhaletrees.com/plants/rhodora/index.html.md) and [Swamp Azalea](https://bluewhaletrees.com/plants/swamp-azalea/index.html.md)
- [Planting-site check](https://bluewhaletrees.com/tools/site-check/index.html.md): for a thrive, struggle or fail verdict on Rosebay Rhododendron, add ?species=rosebay-rhododendron with zone (2 to 10), sun (full, part, shade) and moisture (dry, average, wet) to that address; for example, the verdict for zone 3, part sun and average soil as Markdown is at https://bluewhaletrees.com/tools/site-check/index.html.md?species=rosebay-rhododendron&zone=3&sun=part&moisture=average
- [Companion species for Rosebay Rhododendron](https://bluewhaletrees.com/tools/companions/index.html.md?species=rosebay-rhododendron): the natives that share its ground and the plants that pair with it in a yard.
- [Tree growth estimator](https://bluewhaletrees.com/tools/growth/index.html.md): how the height and trunk projections are made; the estimate for Rosebay Rhododendron as Markdown is at https://bluewhaletrees.com/tools/growth/index.html.md?species=rosebay-rhododendron (add height=, years= and site= poor, average or good)
- [Seed sowing planner](https://bluewhaletrees.com/tools/sowing/index.html.md): how Rosebay Rhododendron is sown, in the chart for every species (treatment, cold days, depth, timing); the dated plan for it as Markdown is at https://bluewhaletrees.com/tools/sowing/index.html.md?species=rosebay-rhododendron (add state= and zone= for your own frost dates, method=fridge for the refrigerator route)
- [Pollination planner](https://bluewhaletrees.com/tools/pollination/index.html.md): what Rosebay Rhododendron needs for a crop and how many to plant, in the table for every species; the verdict for 2 of them as Markdown is at https://bluewhaletrees.com/tools/pollination/index.html.md?plants=rosebay-rhododendron:2
- [Planting-window tool](https://bluewhaletrees.com/tools/planting-window/index.html.md): when to plant Rosebay Rhododendron where you live, as a fall and a spring window from the local frost dates; the windows as Markdown are at https://bluewhaletrees.com/tools/planting-window/index.html.md?species=rosebay-rhododendron&state=MO&zone=6 with your own state and zone in place of those
- [Planting-distance tool](https://bluewhaletrees.com/tools/distance/index.html.md): how far Rosebay Rhododendron goes from a house, a septic field, a walk, wires, a property line and the next tree; the distances as Markdown are at https://bluewhaletrees.com/tools/distance/index.html.md?species=rosebay-rhododendron&near=house,septic,pavement,wires,boundary,tree
- [Bloom and fruit calendar](https://bluewhaletrees.com/tools/calendar/index.html.md): the months Rosebay Rhododendron flowers and fruits, in the grid for every species; its own row and the gaps of a planting with it as Markdown at https://bluewhaletrees.com/tools/calendar/index.html.md?plants=rosebay-rhododendron