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A Forager’s Year

No. 112

Rose of Sharon

Hibiscus syriacus

shrub althea, althea, rose of China

Flowers, buds & pollen flowers and unopened flower buds

Drawing: Britton & Brown, Illustrated Flora (1913)

Find
Common in the right habitat
Effort
Grab & eat
ID risk
Beginner
Origin
non-native ☆
Safety marks
  • Spray risk
Uses
  • Eat raw / salad
  • Cooked vegetable / soup
  • Pesto & sauces
  • Baking & desserts
  • Tea
  • Pickles

Season

  1. Jan
  2. Feb
  3. Mar
  4. Apr
  5. May
  6. Jun
  7. Jul
  8. Aug
  9. Sep
  10. Oct
  11. Nov
  12. Dec

in season peak

Picking: No park we checked allows it. Anywhere else, ask whoever owns or runs the land. See Where you may pick.

What these mean

Find

1 Everywhere · 2 Common in the right habitat · 3 Patchy · 4 Elusive. This is about how much there is, not whether you may pick it. It is based on iNaturalist sightings within 25 km (about 15 miles) of downtown DC, counted on October 3, 2026. The four rules that each plant’s “Find” reason refers to: (A) the estimate is the confirmed sightings, plus the unconfirmed ones (scaled down where the plant has lookalikes in its genus), plus the sightings marked as planted; (B) the tier by estimate: 1,500 or more is tier 1, 250–1,499 tier 2, 50–249 tier 3, under 50 tier 4; (C) tier 1, Everywhere, also needs a source saying the plant is common in lawns, sidewalks, yards or gardens, vacant lots or towns, or at least one DC street tree of it per km of sidewalk, otherwise it is tier 2; (D) if a reliable source says the plant is rare in this region, or that wild plants rarely bear the harvest, only planted sightings count. iNaturalist is a website and phone app where people post photos of the plants and animals they see. A sighting is “research grade” when other users have confirmed what it is; “needs ID” sightings are not confirmed yet, and “cultivated” ones are marked as planted.

Effort

1 Grab & eat · 2 Quick kitchen prep (under about 30 minutes) · 3 Real work (hours, or cooking needed for safety) · 4 Project (days or equipment). Scored on the simplest worthwhile use; each plant’s page says why.

ID risk

How hard it is to harvest safely. Beginner: no dangerous lookalike, and the edible part is not easily confused with a toxic part. Careful: a toxic lookalike, or toxic parts that end up in the harvest unless removed (for example elderberry stems, unripe ground cherries), or other parts of the plant rated medium-or-higher toxicity, with reliable features to separate them. Expert only: a potentially deadly lookalike that is hard to separate, or (for not-recommended harvests like pokeweed) a plant whose safe preparation can’t be guaranteed. Toxic parts that are obviously separate and thrown away anyway (pits, seeds, skins) don’t raise it; the Toxic parts mark carries that warning.

Native or not, and the invader stars

Origin is where the plant comes from: native, non-native, or mixed (the harvest covers both). The stars rate plants on invasive plant lists: ★★★ Virginia DCR “High” or Maryland prohibited invasive · ★★ Virginia “Medium” · ★ Virginia “Low” · ☆ listed only by the Maryland Invasive Species Council or the Mid-Atlantic Plant Invaders guide (advisory) · no stars: native or not listed.

Safety marks and flags

Deadly lookalike / Toxic lookalike: a cited source names a lookalike of that danger, recorded near DC (an iNaturalist sighting within 25 km, a DC street tree, or a Smithsonian listing for DC) and looking like the part you eat. Other lookalikes are still listed, marked “not recorded near DC” or as not looking like the part you eat. Deadly means a source says eating it may be fatal or calls it deadly, or NC State rates it high severity with life-threatening symptoms (sources sometimes disagree; for example Virginia creeper). Each plant’s Lookalikes list says how to tell them apart; “harmless (may be edible)” lookalikes are listed so you know a mix-up isn’t dangerous. Cook first: cooking is needed for safety (for daylilies it is a precaution, not a sourced requirement). Eat in moderation: a source says to limit quantity or frequency (for example oxalates in sorrels and dock, ginkgotoxin, safrole). Spray risk: a source says the plant is commonly treated with herbicide in parks or lawns (invasive control, lawn weeds) or, for ginkgo, sprayed to stop fruiting. Contamination: a source says the plant concentrates pollutants. Each plant’s Safety flags list gives the details and sources.

Seasons

Start, peak and end are given in thirds of a month: early, mid or late. A plant counts as in season for a month if it is in season at any point in that month. Some greens and roots have a second window, in spring or fall; their page shows each window. A season that runs across New Year is shown as one window.

What it looks like

A fast-growing deciduous shrub or small tree of the mallow family, 8 to 12 feet tall, native to eastern Asia and planted for its large summer flowers (NC State). The leaves are alternate, usually 3-lobed, coarsely toothed and 2 to 4 inches long (NC State), and the shrub is one of the last to leaf out in spring (Morton Arboretum). The flowers are 2 to 4 inches across with five crepe-like petals, single or double, in red, white, violet, purple or two-toned (NC State), often with a dark red or maroon throat (Foraging Texas) and a prominent central column of stamens (Morton Arboretum). Each flower lasts only a day or a few days, but the shrub keeps opening new ones for months (NC State; Foraging Texas). The fruit is a brown, 5-valved capsule about 3/4 inch long that stays on the branches through winter (NC State), which helps identify the shrub out of season. The flowers taste mild, with a hint of nectar at the base of the petals, and the unopened buds make an okra substitute (Edible Wild Food); flowers and buds are mucilaginous (slippery) (Edible Wild Food; Foraging Texas).

Safety

No toxicity is reported in the sources checked: NC State lists the flowers as edible and gives no poison warning for rose of Sharon, and Foraging Texas lists no dangers. The University of Minnesota Extension advises trying any new edible flower in small amounts first, because some people react even to flowers considered safe, and eating only flowers that have not been treated with pesticides; do not eat flowers picked from the roadside. Deadly lookalike, not recorded near DC: NC State says rose of Sharon is often confused with the tung oil tree, every part of which, flowers included, is poisonous and may be fatal. Tung is a tree up to 40 feet tall whose pale pink to white, red-veined flowers open in large clusters in spring, before or as the leaves emerge, and whose heart-shaped leaves are 6 to 10 inches long with two red glands at the base (NC State). NC State lists tung only from the Gulf states, Georgia, California and Puerto Rico, and none is logged within 25 km of DC (iNaturalist). Rose of Sharon is a shrub whose solitary flowers open in summer, and its leaves are 3-lobed, coarsely toothed and 2 to 4 inches long (NC State). NC State also pairs rose of Sharon with sunset huskmallow (Abelmoschus manihot), a garden plant with pale yellow, maroon-centered flowers whose young leaves NC State lists as edible. Escaped rose of Sharon is an invasive-plant control target: the USDA Forest Service says general-use herbicides such as glyphosate control it, and Arlington County, the City of Alexandria and the National Park Service’s Mid-Atlantic Exotic Plant Management Team list it as invasive (EDDMapS), so avoid shrubs in parks and natural areas that may have been sprayed.

Lookalikes

  • Tung oil tree Vernicia fordii deadly

    Not recorded near DC. NC State says rose of Sharon is often confused with the tung oil tree, and rates tung’s poison severity high: all parts, flowers included, are toxic if eaten, and poisoning may be fatal. Tung is a tree up to 40 feet tall whose pale pink to white flowers with red veins have 5 to 7 petals, come in large clusters and open in spring, before or as the leaves emerge; its heart-shaped leaves are 6 to 10 inches long with 2 conspicuous red glands at the base. NC State lists it only from Alabama, California, Florida, Georgia, Louisiana, Mississippi, Texas and Puerto Rico, and iNaturalist has no sightings of it within 25 km of DC. Rose of Sharon is a woody shrub whose solitary flowers open in summer, and its leaves are 3-lobed, coarsely toothed and 2 to 4 inches long (NC State).

  • Sunset huskmallow (sunset hibiscus, Tropic Jewel hibiscus) Abelmoschus manihot harmless (may be edible)

    NC State says rose of Sharon is often confused with sunset huskmallow, a shrubby perennial of the mallow family, 4 to 6 feet tall, that is grown as an annual in cooler climates. Its flowers are pale yellow with a maroon center and 4 to 5 inches across, and its leaves are up to 11 inches across with five to nine lobes. NC State lists its young leaves as edible, raw or cooked, but says its seed pods are not edible. Rose of Sharon is a woody shrub whose flowers are red, white, violet, purple or two-toned (NC State).

Safety flags

Safety marks and flags: what this means

Deadly lookalike / Toxic lookalike: a cited source names a lookalike of that danger, recorded near DC (an iNaturalist sighting within 25 km, a DC street tree, or a Smithsonian listing for DC) and looking like the part you eat. Other lookalikes are still listed, marked “not recorded near DC” or as not looking like the part you eat. Deadly means a source says eating it may be fatal or calls it deadly, or NC State rates it high severity with life-threatening symptoms (sources sometimes disagree; for example Virginia creeper). Each plant’s Lookalikes list says how to tell them apart; “harmless (may be edible)” lookalikes are listed so you know a mix-up isn’t dangerous. Cook first: cooking is needed for safety (for daylilies it is a precaution, not a sourced requirement). Eat in moderation: a source says to limit quantity or frequency (for example oxalates in sorrels and dock, ginkgotoxin, safrole). Spray risk: a source says the plant is commonly treated with herbicide in parks or lawns (invasive control, lawn weeds) or, for ginkgo, sprayed to stop fruiting. Contamination: a source says the plant concentrates pollutants. Each plant’s Safety flags list gives the details and sources.

ID risk
Beginner
Why
No dangerous lookalike grows near DC. NC State says rose of Sharon is often confused with the tung oil tree, which is highly poisonous (all parts, flowers included; may be fatal), but tung is not recorded near DC: NC State lists it only from the Gulf states, Georgia, California and Puerto Rico, and iNaturalist has no sightings within 25 km. Tung is a tree whose clustered, red-veined, pale pink to white flowers open in spring before or as the leaves emerge; rose of Sharon bears solitary flowers on a woody shrub in summer. Sunset huskmallow, also paired by NC State, is not poisonous.
Soil risk
moderate
ID risk: what this means

How hard it is to harvest safely. Beginner: no dangerous lookalike, and the edible part is not easily confused with a toxic part. Careful: a toxic lookalike, or toxic parts that end up in the harvest unless removed (for example elderberry stems, unripe ground cherries), or other parts of the plant rated medium-or-higher toxicity, with reliable features to separate them. Expert only: a potentially deadly lookalike that is hard to separate, or (for not-recommended harvests like pokeweed) a plant whose safe preparation can’t be guaranteed. Toxic parts that are obviously separate and thrown away anyway (pits, seeds, skins) don’t raise it; the Toxic parts mark carries that warning.

Soil risk: what this means

Based on the part you eat, following the urban-soil lead guidance on the Field safety page: higher for greens, shoots and roots; moderate for flowers; low for fruit, nuts and sap.

Field safety for every outing (poison ivy, ticks, soil, and more)

When to pick

Starts
mid Jun
Peak
early Aug–late Aug
Ends
mid Oct

Near DC rose of Sharon flowers from mid-June into October, most heavily from July through mid-September. iNaturalist records of plants in flower within 25 km of DC run from mid-June to late September, with the most in August. The U.S. National Arboretum in Washington says its rose of Sharon cultivars flower from June to September, and that 'Diana', which sets little seed, blooms from late June until frost. The Missouri Botanical Garden gives a bloom time of June to October, and Virginia Tech says the shrub flowers in late summer, when few other shrubs are in bloom. iNaturalist records of flower buds near DC run from July to September. Each flower lasts only a day or a few days (NC State; Foraging Texas).

How the dates were worked out

Every start, peak and end was re-checked in October 2026. “Sourced” means a source opened during the check states that timing for the DC or Mid-Atlantic area. “Estimated” means no source states it exactly; the reason, the evidence and the source links are under “How the dates were worked out” on each plant’s page. Peaks are often estimated, because few sources name a peak. iNaturalist evidence means research-grade sightings near DC, by month, of the plant at that stage (for example, in fruit). iNaturalist is a website and phone app where people post photos of the plants and animals they see. A sighting is “research grade” when other users have confirmed what it is; “needs ID” sightings are not confirmed yet, and “cultivated” ones are marked as planted.

Season basis: estimated: start, peak, end

Start

estimated: No source gives a date for the wild or escaped shrubs here; the National Arboretum’s June start is for its cultivars, and the first DC-area flowering records fall in mid-June.

Peak

estimated: No source names a peak month; August has the most DC-area flowering records and lies in the middle of the heavy-flowering stretch from July to mid-September.

End

estimated: Botanic-garden and National Arboretum sources run flowering into October or until frost, but the DC-area flowering records thin out after mid-September and the last regional one is in the second week of October; mid October keeps the documented tail without running to frost, which the frost statements make only for low-seed cultivars.

Evidence

start: iNaturalist research-grade flowering records within 25 km by week: first in week 25 (2 records; Jun 18-24); in MD, VA and DC first in week 24 (1) and week 25 (6). U.S. National Arboretum (Washington, DC): 'Plants flower from June to September' ('Aphrodite', 'Helene', 'Minerva'); 'Diana': 'Bloom begins in late June'. Missouri Botanical Garden: 'Bloom Time: June to October'. | peak: iNaturalist research-grade flowering records within 25 km by month: Jun 3, Jul 25, Aug 35, Sep 28; MD+VA+DC by week rise from week 27 (13) to a plateau of 14-27 a week through week 37 (mid-September), then 9, 4, 0, 1. Virginia Tech: 'This is a large shrub which flowers in late summer when few other shrubs are in bloom.' | end: Missouri Botanical Garden: 'Bloom Time: June to October'. U.S. National Arboretum: 'Diana' 'Bloom begins in late June and continues in profusion until frost'; the triploids show 'continuous flowering until felled by autumn’s frost'. iNaturalist research-grade flowering records: within 25 km last in week 39 (2 records; Sep 24-30); MD+VA+DC one in week 41 (Oct 8-14).

Where to look

Mostly yard and garden shrubs, with escapes in stream-valley parks: logged most in Rock Creek Park, the Four Mile Run stream valley, Sligo Creek Stream Valley Park, along the Mount Vernon Trail and in Bluemont Park, all look-but-don’t-pick. No listed park allows picking flowers, so pick from yard shrubs with the owner’s permission.

Habitats
street & yard trees (planted), disturbed ground & waste places, woods edges, trailsides & thickets
Habitats: what this means

Listed where the plant’s own sources place it in that habitat. “Disturbed ground & waste places” means a cited source places it on disturbed areas, sites, soil or ground, on waste places or waste ground, on construction or abandoned building sites (old home sites count), on rubble or in strip mines. When the source gives examples of the disturbed places, at least one example must be of that kind. Examples that do not count: natural or forestry disturbance (treefall gaps, fire, windthrow, flood scour, old riverbanks and creeks, clear-cuts); roadsides, railroads and rights-of-way; and abandoned fields, pastures and farmland, which are “Old fields & meadows”. “Vacant lots” only where a source says vacant or empty lots.

Most-logged places

None of the most-logged places allows picking.

No picking here (5 places)
  • Rock Creek Park

    65 sightings · Legal to pick: no · see them on iNaturalist

    Look but don’t pick: Rock Creek Park’s compendium bans gathering any fruit, nut, berry, seed or greenery.

  • Four Mile Run stream valley (Arlington/Alexandria)

    31 sightings · Legal to pick: no · see them on iNaturalist

    Look but don’t pick: Arlington County park rules (flora shall not be removed or disturbed) and Alexandria’s permit rule both apply.

  • Sligo Creek Stream Valley Park

    24 sightings · Legal to pick: no · see them on iNaturalist

    Look but don’t pick: Montgomery/Prince George’s parks (M-NCPPC) ban harvesting vegetation without a permit.

  • Mount Vernon Trail

    19 sightings · Legal to pick: no · see them on iNaturalist

    Look but don’t pick: GW Memorial Parkway sites (incl. Great Falls VA, Theodore Roosevelt Island, Dyke Marsh) designate nothing for gathering.

  • Bluemont Park

    13 sightings · Legal to pick: no · see them on iNaturalist

    Look but don’t pick: Arlington County park rules say flora shall not be removed or disturbed.

Most-logged places: what this means

The places with the most research-grade iNaturalist sightings within 25 km of downtown DC (re-counted in October 2026 over every named place, campuses, condominiums and private grounds included), each marked legal to pick or not. A sighting inside several named places counts once, for the smallest of them, but a sighting inside a National Park Service park never counts for a private, campus or unchecked place. iNaturalist shows where people walk and log plants, not true abundance. Private campuses, condominiums, museums, estates and utility land (Pepco’s power-line land near Sligo Creek) are marked “no” (pick only with the owner’s permission); public university campuses, city parks and other places whose picking rules were not checked (county stormwater land, the U.S. Capitol Grounds, Greenbelt’s North Woods, federal facilities such as the National Zoo) are “unknown”. A place needs at least 2 sightings, so plants with very few sightings have no places. At-risk plants (butternut, nannyberry, American chestnut, ramps, riverbank goldenrod) get places like every other plant; each page says why the plant is at risk and gives any advice its sources give. For some places, mostly Rock Creek Park, the iNaturalist map shows more sightings than the count here, because a map link cannot leave out exactly the sightings credited to another place. iNaturalist is a website and phone app where people post photos of the plants and animals they see. A sighting is “research grade” when other users have confirmed what it is; “needs ID” sightings are not confirmed yet, and “cultivated” ones are marked as planted.

Ways to use it

  • eat the flowers raw in salads: mild, with a hint of nectar at the base of the petals (Edible Wild Food)
  • unopened flower buds as a vegetable, an okra substitute (Edible Wild Food)
  • closed flower buds pickled or fried like okra pods (Foraging Texas)
  • slippery (mucilaginous) buds to thicken soups and sauces (Edible Wild Food)
  • tea from the flowers (Edible Wild Food)
  • petals added to rice cakes and tea, a use in Korea at times of food scarcity (Korea’s National Institute of Forest Science)

Keeping

Use them the day you pick them, or dry the flowers for tea.

Use within
pick & use same day
Keeps fresh
Pick flowers and buds the day you will use them, no more than one day early, wash them gently, let them dry and refrigerate them in plastic bags until use (University of Minnesota; general guidance for edible flowers).
Keeping basis
general guidance for its type

Ways to keep it

  • Dry as researched: dry/dehydrate (tea or seasoning); canning: n/a (not shelf-canned)

    Edible Wild Food suggests a tea from the flowers. Use the general herb method: NCHFP: dehydrate at 95-115°F (up to 125°F in humid weather) until crisp, then store airtight in a cool, dry, dark place.

Canning: what this means

Shelf-stable canning, three levels. Lab-tested: a lab-tested recipe from the National Center for Home Food Preservation (NCHFP) or Oregon State covers this fruit and product, or a generic recipe for its kind (the line says so, for example chokeberry). Extension recipe: a published Extension recipe (University of Alaska Fairbanks, written for Alaska species; University of Maine’s dandelion jelly), or a process that is safe only with a pH meter; follow it exactly, never improvise. No tested recipe: refrigerate or freeze, don’t can. “Hot-bottled syrup” = maple and walnut syrup, which keep when bottled hot at full syrup density. The Canning line names the exact product each source covers, for example “whole berries” or “juice”; a product not named there (such as juice from a berry with only a whole-berry recipe) has no tested recipe.

Keeping basis: what this means

“Specific to this plant” or “general guidance for its type” (for example NCHFP guidance for leafy greens applied to a wild green).

Nutrition

Not researched: in October 2026, only the calendar’s plants of the month and chicory leaves were researched.

Native or not

NC State says rose of Sharon has been reported to be invasive in some states, including Virginia and Kentucky. Some cultivars bred at the U.S. National Arboretum ('Diana', 'Helene', 'Minerva', 'Aphrodite') set little or no seed.

Origin
non-native
Native range
eastern Asia (south China and Taiwan per NC State; China to India per the Missouri Botanical Garden)
Invader credit
☆
Virginia invasive rank
not listed
Maryland invasive status
Advisory (MISC list)
Native or not, and the invader stars: what this means

Origin is where the plant comes from: native, non-native, or mixed (the harvest covers both). The stars rate plants on invasive plant lists: ★★★ Virginia DCR “High” or Maryland prohibited invasive · ★★ Virginia “Medium” · ★ Virginia “Low” · ☆ listed only by the Maryland Invasive Species Council or the Mid-Atlantic Plant Invaders guide (advisory) · no stars: native or not listed.

Virginia DCR, Virginia Invasive Plant Species List (effective September 2024), verbatim: "Under the DCR Invasive Species Assessment Protocol, approved by the Virginia Invasive Species Working Group, January 2024, species were ranked as exhibiting high, medium or low levels of invasiveness based on their threat to natural communities and native species. Invasiveness rank is higher for species that: • Alter ecosystem processes, such as succession, hydrology or fire regime. • Are capable of invading undisturbed natural communities. • Cause substantial impacts on rare or vulnerable species or natural communities or high-quality examples of more common communities. • Are found widely distributed and generally abundant where present. • Disperse readily to new areas. • Are difficult to control." The list also states: "The list is for educational purposes only and has no regulatory authority."

Maryland Department of Agriculture, Maryland Prohibited Invasive Plant Law and Regulations page, verbatim: "Plants on the Maryland Prohibited Invasive Plant List may not be added to stock after the effective date and should not be sold after their phase-out period ends."

No official DC invasive plant list was found.

How the ratings were set

Find
Common in the right habitat Estimate 1,729 = 1,277 research-grade iNaturalist sightings within 25 km + 230 needs-ID sightings counted at 48% (1,277 of the 2,654 research-grade Hibiscus sightings here are rose of Sharon) + 341 'cultivated' (planted) sightings (rule A); that is tier 1 by count (rule B). Rule C: none of its sources says it is common in, or a weed of, an everyday place (lawns, sidewalks, yards or gardens, vacant lots, towns), and DC’s street-tree inventory lists no rose of Sharon, so it cannot be tier 1 (Everywhere). Rule D does not apply: the Digital Atlas of the Virginia Flora calls its escapes in Virginia "Infrequent; scattered throughout", which is not rare or very infrequent. Final tier 2.
Effort
Grab & eat Pick open flowers or unopened buds and eat them raw, in a salad or as a nibble; buds pickled or fried like okra are a 2.
Find: what this means

1 Everywhere · 2 Common in the right habitat · 3 Patchy · 4 Elusive. This is about how much there is, not whether you may pick it. It is based on iNaturalist sightings within 25 km (about 15 miles) of downtown DC, counted on October 3, 2026. The four rules that each plant’s “Find” reason refers to: (A) the estimate is the confirmed sightings, plus the unconfirmed ones (scaled down where the plant has lookalikes in its genus), plus the sightings marked as planted; (B) the tier by estimate: 1,500 or more is tier 1, 250–1,499 tier 2, 50–249 tier 3, under 50 tier 4; (C) tier 1, Everywhere, also needs a source saying the plant is common in lawns, sidewalks, yards or gardens, vacant lots or towns, or at least one DC street tree of it per km of sidewalk, otherwise it is tier 2; (D) if a reliable source says the plant is rare in this region, or that wild plants rarely bear the harvest, only planted sightings count. iNaturalist is a website and phone app where people post photos of the plants and animals they see. A sighting is “research grade” when other users have confirmed what it is; “needs ID” sightings are not confirmed yet, and “cultivated” ones are marked as planted.

Effort: what this means

1 Grab & eat · 2 Quick kitchen prep (under about 30 minutes) · 3 Real work (hours, or cooking needed for safety) · 4 Project (days or equipment). Scored on the simplest worthwhile use; each plant’s page says why.

Sources

33 sources, each linked to the original.

  1. Rock Creek Park Superintendent’s Compendium National Park ServiceBacks up: picking rules
  2. Non-Native Invasive Terrestrial Plant Species in the State of Maryland (updates approved through the April 18, 2024 MISC meeting) Maryland Invasive Species CouncilBacks up: picking rules, native or invasive status
  3. Rose-of-Sharon (Hibiscus syriacus) The Morton ArboretumBacks up: description, picking rules
  4. Hibiscus syriacus (Rose of Sharon, Shrub Althea) NC State Extension Gardener Plant ToolboxBacks up: description, safety, season, native or invasive status
  5. Rose of Sharon Foraging Texas (Mark Vorderbruggen)Backs up: description, uses, safety, season
  6. Rose Of Sharon: Identification, Leaves, Bark & Habitat (Hibiscus syriacus) Edible Wild FoodBacks up: description, uses, keeping
  7. DC street-tree inventory (DDOT Urban Forestry, UFA Street Trees layer): living trees by species, queried 2026-10-05 (no Hibiscus syriacus) District of Columbia (DDOT Urban Forestry Division, via DC GIS)Backs up: findability
  8. iNaturalist research-grade observations of Hibiscus syriacus within 25 km of downtown DC iNaturalistBacks up: findability
  9. Annotated Checklist of the Vascular Plants of the Washington-Baltimore Area, Part I (Shetler & Orli, 2000) Smithsonian Institution, National Museum of Natural History, Department of BotanyBacks up: habitat
  10. Rose of Sharon, Hibiscus syriacus Linnaeus Maryland Biodiversity ProjectBacks up: habitat
  11. Rose of Sharon (Hibiscus syriacus): Invasive Plant Fact Sheet Master Gardeners of Northern Virginia (Virginia Cooperative Extension)Backs up: habitat, picking rules
  12. Hibiscus syriacus L. (Digital Atlas of the Virginia Flora) Virginia Botanical Associates (Digital Atlas of the Virginia Flora)Backs up: habitat, findability
  13. Weed of the Week: Rose of Sharon, Hibiscus syriacus L. (WOW 07-03-06; copy hosted by Valparaiso Parks) USDA Forest Service, Forest Health StaffBacks up: habitat, safety, safety details
  14. Herbs (drying) National Center for Home Food Preservation (University of Georgia)Backs up: keeping
  15. USDA PLANTS Database: Hibiscus syriacus (HISY), native status USDA NRCSBacks up: native or invasive status
  16. Virginia Invasive Plant Species List (effective date: September 2024) Virginia Department of Conservation and Recreation, Division of Natural HeritageBacks up: native or invasive status
  17. Maryland Prohibited Invasive Plant Law and Regulations (Maryland Prohibited Invasive Plant List, updated January 2026; additions effective July 15, 2026; 'Next Plants To Be Assessed' 2026-2027) Maryland Department of Agriculture, Plant Protection & Weed ManagementBacks up: native or invasive status
  18. Plant Invaders of Mid-Atlantic Natural Areas, Field Guide (Swearingen & Fulton, 2022; successor to the NPS/USFWS 5th ed., 2017) Mid-Atlantic Invasive Plant Council / Passiflora Press (hosted by Bugwood/Mid-Atlantic Invaders Tool)Backs up: native or invasive status
  19. Invasive Plants in the District DC Department of Energy & EnvironmentBacks up: native or invasive status
  20. Edible flowers University of Minnesota ExtensionBacks up: safety, keeping
  21. Vernicia fordii (Tung Oil Tree) NC State Extension Gardener Plant ToolboxBacks up: safety, safety details
  22. Abelmoschus manihot (Sunset Huskmallow) NC State Extension Gardener Plant ToolboxBacks up: safety, safety details
  23. iNaturalist verifiable observations of Vernicia fordii within 25 km of downtown DC (none) iNaturalistBacks up: safety, safety details
  24. rose of Sharon, Hibiscus syriacus (EDDMapS species page: invasive listing sources) EDDMapS (University of Georgia Center for Invasive Species and Ecosystem Health)Backs up: safety, safety details
  25. Rose of Sharon research-grade flowering observations within 25 km of DC, by week iNaturalistBacks up: season
  26. Rose of Sharon research-grade flowering observations within 25 km of DC, by month iNaturalistBacks up: season
  27. Rose of Sharon research-grade flowering observations, Maryland, Virginia and DC, by week iNaturalistBacks up: season
  28. Rose of Sharon research-grade flower-budding observations within 25 km of DC, by month iNaturalistBacks up: season
  29. Rose-of-Sharon, Shrub Althea (Hibiscus syriacus) (Publication 2901-1066, reviewed March 2024) Virginia Cooperative Extension (Virginia Tech)Backs up: season, habitat
  30. Hibiscus syriacus 'Diana' (U.S. National Arboretum Plant Introduction) U.S. National Arboretum, USDA Agricultural Research ServiceBacks up: season, native or invasive status
  31. Hibiscus syriacus 'Aphrodite', 'Helene', and 'Minerva' (U.S. National Arboretum Plant Introduction) U.S. National Arboretum, USDA Agricultural Research ServiceBacks up: season, native or invasive status
  32. Hibiscus syriacus (Plant Finder) Missouri Botanical GardenBacks up: season, native or invasive status
  33. Nutritional composition and phytochemical screening in different parts of Hibiscus syriacus L. (Food Science & Nutrition 10:3034-3042, 2022; Park et al.) Korea’s National Institute of Forest Science (Food Science & Nutrition, Wiley)Backs up: uses