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A Forager’s Year

No. 52

Ground cherry

Physalis longifolia, P. heterophylla, P. virginiana and related Physalis spp.

wild ground cherry

Fruit fully ripe fruit (from husk)

Drawing: Britton & Brown, Illustrated Flora (1913)

Find
Common in the right habitat
Effort
Grab & eat
ID risk
Careful
Origin
native
Safety marks
  • Deadly lookalike
  • Toxic parts
Uses
  • Eat raw / salad
  • Pesto & sauces
  • Baking & desserts
  • Jam & jelly
  • Dried fruit & leather

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

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. 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

Low, branching herbaceous perennials in the nightshade (tomato) family. They have nodding yellowish bell-shaped flowers with dark centers. Each fruit is a small round berry, under 1 in, enclosed in an inflated, papery, lantern-like husk. When ripe, the berry is yellow to orange and the husk is tan and papery. Flavor ranges from sweet and fruity (like pineapple or tomato) to somewhat bitter, depending on species.

Safety

UNRIPE FRUIT AND ALL OTHER PARTS ARE TOXIC: leaves, stems, flowers and green fruit contain solanine-type alkaloids (vomiting, diarrhea, respiratory depression). Eat only fully ripe berries from dry tan husks. LOOKALIKE: Carolina horsenettle (Solanum carolinense), a common prickly nightshade weed in the same habitats, has yellow, tomato-like berries with NO papery husk, and they are poisonous. The husk is essential to identification.

Lookalikes

Safety flags

Safety marks and flags: what this means

Deadly lookalike / Toxic lookalike: a cited source names a lookalike of that danger. 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
Careful
Why
Lookalike Carolina horsenettle (Solanum carolinense) has poisonous yellow tomato-like berries with NO papery husk and prickly stems; unripe ground cherries are also toxic. The dry tan husk is the key feature.
Handling hazards
Thorns (minor)
Soil risk
low
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.

Handling hazards: what this means

Stings, thorns, irritating or phototoxic sap, staining hulls and spiny husks, with a severity: minor = brief discomfort; moderate = rash or blisters lasting days; serious = burns, scarring or medical care possible.

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
late Jul
Peak
late Aug–late Aug
Ends
late Oct

Wild ground cherries ripen from mid-to-late summer (NC State), and Penn State, writing about garden ground cherries, expects ripe fruit from late summer through autumn, tapering off as the weather cools. Ripe fruit often drops to the ground still inside its husk (Penn State, garden ground cherries). Gather fallen husks, and eat only berries that are fully yellow or orange inside a dry tan husk; unripe berries carry the most toxin (Penn State Master Gardeners).

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: Mid-to-late summer is not dated; late July matches the first DC fruiting records.

Peak

estimated: No source gives a peak; late August falls where the sources overlap and where DC records are most numerous.

End

estimated: Both Penn State pages are about garden ground cherries. Fruit keeps coming until cold weather, and frost usually arrives near DC in early-to-mid November, so late October is used.

Evidence

start: NC State: clammy ground cherry fruit is green at first 'but become yellow at maturity in mid to late summer'. DC iNaturalist research-grade fruiting records for Physalis begin in mid-July: 7 records from Jul 16 to Nov 3, plus one stray March record (a dried husk). | peak: NC State: mid-to-late summer. Penn State: 'Expect ripened fruit from late summer through autumn.' DC iNaturalist Physalis records (all stages) peak in August (40) and September (41). | end: Penn State: ripened fruit 'from late summer through autumn'; flowering and fruiting decline as the air cools. Penn State Master Gardeners: 'late summer through autumn'. The last DC iNaturalist Physalis fruiting record is in early November.

Where to look

Scattered plants in sunny disturbed ground, garden edges and open woods; logged in Rock Creek Park and Glencarlyn Park (no picking), so look in Virginia state parks or on private field edges and gardens with permission.

Habitats
disturbed ground & waste places, old fields & meadows
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.

Ask first: rules unclear or not checked

  • C&O Canal NHP (towpath, Georgetown to Great Falls MD and beyond)

    3 sightings · Legal to pick: ambiguous · see them on iNaturalist

    Ambiguous: the C&O compendium allows edible fruits, nuts and berries generally but sets no limit for this one; ask the park first. Of these, 1 is at Carderock.

No picking here (4 places)
  • Glencarlyn Park

    6 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.

  • Dumbarton Oaks Park

    5 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.

  • Rock Creek Park

    3 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.

  • Cabin John Regional Park

    3 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.

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 (rugosa rose) have no places. No most-logged places are named for at-risk plants (ramps, chinquapin, American chestnut); chinquapin’s page names Mason Neck State Park, where picking is legal, and asks you to leave most nuts. 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 fresh (ripe only)
  • jam/preserves
  • pie
  • sauces
  • dried
  • salsa

Keeping

Keep the fruit in its husks somewhere cool for up to about 3 months, or husk and freeze it (6 months).

Use within
weeks
Keeps fresh
In their husks in a cool area, up to 3 months; out of the husk in the refrigerator, 2-3 weeks (Penn State, written for garden ground cherries). Use only fully ripe fruit.
Canning
no tested recipe: refrigerate or freeze, don’t can
Keeping basis
specific to this plant

Ways to keep it

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

    Dry like raisins (Penn State).

  • Freeze as researched: freeze; canning: n/a (not shelf-canned)

    Freeze on a baking sheet, then bag; keeps 6 months (Penn State).

  • Jam/jelly as researched: jam/jelly; canning: no tested recipe — refrigerate or freeze

    Jams and preserves are listed uses. No tested canning recipe names ground cherries, so refrigerate or freeze them.

  • Store whole as researched: store in shell; canning: n/a (not shelf-canned)

    Leave the berries in their papery husks in a cool area, up to about 3 months (Penn State).

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

Origin
native
Native range
North America (eastern & central US)
Virginia invasive rank
not listed
Maryland invasive status
not listed
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 322 = 149 research-grade iNaturalist sightings within 25 km + 154 needs-ID sightings counted in full (the harvest is the whole genus) + 19 'cultivated' (planted) sightings (rule A); that is tier 2 by count (rule B). Rule D does not apply: the Digital Atlas of the Virginia Flora says longleaf ground-cherry, the most-logged ground-cherry here, is "Frequent in the mountains and Piedmont; rare in the Coastal Plain", but the 25 km circle takes in both the Piedmont and the Coastal Plain, and a source that calls the plant frequent in one part of the circle outweighs its rare statement about another part. Final tier 2.
Effort
Grab & eat Gather ripe fruit from dry tan husks, peel off the husk and eat.
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

23 sources, each linked to the original.

  1. Rock Creek Park Superintendent’s Compendium (2026) National Park Service, Rock Creek ParkBacks up: picking rules
  2. Prince William Forest Park Superintendent’s Compendium National Park Service, Prince William Forest ParkBacks up: picking rules
  3. Longleaf Groundcherry Virginia Museum of Natural HistoryBacks up: description, uses, habitat
  4. iNaturalist research-grade observations of Physalis (genus) within 25 km of downtown DC iNaturalistBacks up: findability
  5. 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
  6. Physalis heterophylla (Clammy Ground-cherry) (Digital Atlas of the Virginia Flora) Virginia Botanical Associates (Digital Atlas of the Virginia Flora)Backs up: habitat
  7. Physalis longifolia var. subglabrata (Longleaf Ground-cherry) (Digital Atlas of the Virginia Flora) Virginia Botanical Associates (Digital Atlas of the Virginia Flora)Backs up: habitat
  8. Physalis virginiana (Virginia Ground-cherry) (Digital Atlas of the Virginia Flora) Virginia Botanical Associates (Digital Atlas of the Virginia Flora)Backs up: habitat
  9. USDA PLANTS Database: Physalis longifolia (PHLO4), native status USDA NRCSBacks up: native or invasive status
  10. USDA PLANTS Database: Physalis heterophylla (PHHE5), native status USDA NRCSBacks up: native or invasive status
  11. USDA PLANTS Database: Physalis virginiana (PHVI5), native status USDA NRCSBacks up: native or invasive status
  12. Virginia Invasive Plant Species List (effective date: September 2024) Virginia Department of Conservation and Recreation, Division of Natural HeritageBacks up: native or invasive status
  13. 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
  14. 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: native or invasive status
  15. 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
  16. Invasive Plants in the District DC Department of Energy & EnvironmentBacks up: native or invasive status
  17. Solanum carolinense (Carolina Horsenettle) NC State Extension Gardener Plant ToolboxBacks up: safety
  18. Wild ground cherry research-grade observations within 25 km of DC, by week (fruiting annotation) iNaturalistBacks up: season
  19. Wild ground cherry research-grade observations within 25 km of DC, by month iNaturalistBacks up: season
  20. Physalis heterophylla (Clammy Ground Cherry) NC State Extension Gardener Plant ToolboxBacks up: season, description, uses, habitat, safety
  21. Physalis spp. (Ground Cherry) NC State Extension Gardener Plant ToolboxBacks up: season, description, uses, safety, habitat
  22. Growing Ground Cherries Penn State ExtensionBacks up: season, description, uses, safety, keeping
  23. Off the Beaten Path: Ground Cherries Penn State Extension Master Gardener Program (Susquehanna County)Backs up: season, safety