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A Forager’s Year

No. 106

White sweet clover

Melilotus albus (also M. officinalis)

sweet white clover, white sweetclover, white melilot; also yellow sweet clover

Nut & seed ripe seeds (in tiny one- or two-seeded pods), used as a spice

Drawing: Britton & Brown, Illustrated Flora (1913)

Find
Common in the right habitat
Effort
Quick kitchen prep
ID risk
Beginner
Origin
non-native
Uses
  • Spice & seasoning

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: The rules are unclear. Ask the park. 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.

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 tall biennial of the pea family whose white flower spikes turn into tiny oval pods, 3 to 6 mm long and covered in a net of ridges, each holding one or two seeds about 2 mm long that ripen to brown (Minnesota Wildflowers). Edible Wild Food says one plant can produce 14,000 to 350,000 seeds, and FEIS notes that the seeds often stay on the plant through the winter. The plant has a sweet, vanilla-like scent from coumarin (Cornell University). Yellow sweet clover’s seeds are used the same way (Eat The Weeds; Foraging Texas); it has yellow flowers, and its pods are wrinkled rather than veiny (FEIS).

Safety

Use as a spice, in small amounts. The plant contains coumarin, the vanilla-scented compound behind its smell (Cornell University; FEIS), and the sources checked give no coumarin figure for the seeds themselves. Germany’s Federal Institute for Risk Assessment (BfR) names melilot among the plants that contain coumarin and says that in especially sensitive people even fairly small amounts of coumarin can cause liver damage, which is usually reversible. Edible Wild Food recommends the plant only occasionally or as a spice, and Eat The Weeds says to use it carefully and sparingly. Gather only clean, dry seed heads and keep the seeds dry: molds turn sweet clover’s coumarin into dicoumarol, a blood thinner (Cornell University; NDSU Extension), and Eat The Weeds says moldy clover should never be used. People taking blood thinners such as warfarin should not eat sweet clover: a pharmacy review lists it among herbs that may increase bleeding risk with warfarin (American Journal of Health-System Pharmacy), and Foraging Texas gives the same warning. The European Medicines Agency reports allergic reactions to melilot preparations and lists allergy to melilot or coumarin as a reason not to use them. The lookalike is harmless: alfalfa, with purple flowers and leaflets toothed only at the tips, is edible (NDSU Extension; Edible Wild Food). Avoid roadsides and field edges that may be sprayed with herbicide.

Lookalikes

  • Alfalfa Medicago sativa harmless (may be edible)

    Without flowers, sweet clover leaves look like alfalfa’s, but sweet clover leaflets are toothed all around the edge, while alfalfa’s are toothed only at the tips (NDSU Extension). Alfalfa has short clusters of purple flowers, and Edible Wild Food lists its leaves and young shoots as edible.

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 toxic lookalike is named. Alfalfa (purple flowers) is edible, and yellow sweet clover (yellow flowers, wrinkled rather than veiny pods; FEIS) is gathered and used the same way.
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.

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
–
Ends
late Oct

Gather ripe, brown pods from late summer into fall. FEIS reports ripe seed by late July for yellow sweet clover and by early August for white sweet clover in southern Ontario, and says the seeds often stay on the plant through the winter; no source gives ripening dates for the DC area, where sweet clover blooms from early May into September (iNaturalist).

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, end

Start

estimated: The only ripening dates are from southern Ontario (yellow sweet clover by late July, white by early August); DC plants bloom from early May, so ripe seed may come earlier here, but no regional source says so.

Peak

End

estimated: Seeds can hang on into winter, but no source says they are still worth gathering then; the window closes in late October, when DC records of the standing plants thin out.

Evidence

start: FEIS: 'In southern Ontario, there were usually ripe yellow sweetclover seeds by late July, but it was early August before ripe white sweetclover seeds occurred.' DC iNaturalist (white and yellow together): flowering-annotated records start in early May (May 3/10/17); fruiting-annotated records May 0/0/1, June 1/0/0, August 0/0/2, October 0/1/0. | peak: FEIS gives a first-ripe date only. | end: FEIS: 'Often sweetclover seeds remained on the plant through the winter'. DC iNaturalist fruiting-annotated records (white and yellow): month 5: 1, month 6: 1, month 8: 2, month 10: 1; all records October 1/6/2, November 3/1/2.

Where to look

Sunny fields, roadsides and disturbed ground, logged most along the C&O Canal towpath, at Dyke Marsh and at Huntley Meadows; the C&O Canal and Virginia state parks may or may not count the tiny seed pods as allowed 'fruits' (ask the park first); Dyke Marsh, Huntley Meadows, Rock Creek Park and the Four Mile Run parks ban picking, so the sure option is private land with the owner’s permission.

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

Ask first: rules unclear or not checked

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

    68 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.

No picking here (4 places)
  • Dyke Marsh Wildlife Preserve

    28 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.

  • Huntley Meadows Park

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

    Look but don’t pick: Fairfax County parks ban removing any plant part without written permission.

  • Rock Creek Park

    25 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)

    21 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.

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

  • spice (Edible Wild Food; Eat The Weeds)
  • seasoning for bean and split-pea soups (PFAF)
  • seed pods cooked with the leaves in a bean soup (PFAF)

Keeping

Dry fully, store airtight in a cool, dark, dry place, use within a year, and throw out any that mold.

Use within
months+
Keeps fresh
Fully dried seeds keep for months in a clean, dry, airtight jar in a cool, dark place (general guidance for dried foods). Check the jar for moisture and throw out anything moldy.
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)

    NCHFP: cool dried food completely before packing, since warm food can sweat enough moisture for mold to grow; store in clean, dry jars in a cool, dry, dark place, 4 months to 1 year, and discard moldy food. With sweet clover mold matters doubly, because molds turn its coumarin into the blood thinner dicoumarol (Cornell University).

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

Some botanists, and USDA PLANTS, treat white and yellow sweet clover as one species, Melilotus officinalis; FEIS, the Virginia flora and the Smithsonian checklist keep them separate. Both are introduced from Eurasia.

Origin
non-native
Native range
Eurasia (central Europe to Tibet)
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 852 = 685 research-grade iNaturalist sightings within 25 km + 164 needs-ID sightings counted in full (white and yellow sweet clover are the only Melilotus with research-grade sightings here) + 3 'cultivated' (planted) sightings (rule A); that is tier 2 by count (rule B). Final tier 2.
Effort
Quick kitchen prep Strip ripe, dry pods from the seed spikes, rub and winnow out the seeds, make sure they are fully dry, and grind a little as a spice.
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

32 sources, each linked to the original.

  1. Rock Creek Park Superintendent’s Compendium National Park ServiceBacks up: picking rules
  2. 4VAC5-30-50. Flowers, plants, minerals, etc. Virginia Law Library (law.lis.virginia.gov)Backs up: picking rules
  3. C&O Canal NHP Superintendent’s Compendium, effective September 11, 2026 National Park Service, Chesapeake and Ohio Canal NHPBacks up: picking rules
  4. 36 CFR 2.1 - Preservation of natural, cultural and archeological resources Legal Information Institute, Cornell Law School (text of federal regulation)Backs up: picking rules
  5. Melilotus albus (White Sweet Clover) Minnesota WildflowersBacks up: description, habitat
  6. Coumarin Glycosides (Plants Poisonous to Livestock) Cornell University Department of Animal ScienceBacks up: description, safety, keeping
  7. Melilotus alba, M. officinalis (C. L. Gucker, 2009) USDA Forest Service, Fire Effects Information System (FEIS)Backs up: description, season, safety, native or invasive status
  8. Sweet White Clover (Melilotus albus) Edible Wild FoodBacks up: description, uses, safety
  9. iNaturalist research-grade observations of Melilotus albus + M. officinalis within 25 km of downtown DC iNaturalistBacks up: findability
  10. Melilotus albus Medikus (White Sweet-clover) Digital Atlas of the Virginia Flora (Virginia Botanical Associates)Backs up: habitat
  11. Melilotus officinalis (L.) Lam. (Yellow Sweet-clover) Digital Atlas of the Virginia Flora (Virginia Botanical Associates)Backs up: habitat
  12. Checklist of the Vascular Plants of the Washington-Baltimore Area (Shetler & Orli) Smithsonian Institution, Department of BotanyBacks up: habitat
  13. Packaging and Storing Dried Foods National Center for Home Food Preservation (University of Georgia)Backs up: keeping
  14. USDA PLANTS Database: Melilotus officinalis (MEOF; USDA includes Melilotus alba, MEAL2, in this species), native status USDA NRCSBacks up: native or invasive status
  15. Virginia Invasive Plant Species List (effective date: September 2024) Virginia Department of Conservation and Recreation, Division of Natural HeritageBacks up: native or invasive status
  16. 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
  17. 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
  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. Sweetclover Hay Can be Toxic (Aug. 3, 2020) North Dakota State University ExtensionBacks up: safety
  21. Potential interactions between alternative therapies and warfarin (Heck, DeWitt & Lukes, American Journal of Health-System Pharmacy, 2000) American Journal of Health-System Pharmacy (Purdue University School of Pharmacy), peer-reviewed; via PubMedBacks up: safety
  22. Assessment report on Melilotus officinalis (L.) Lam., herba (EMA/HMPC/44165/2016, 2017) European Medicines Agency, Committee on Herbal Medicinal ProductsBacks up: safety
  23. FAQ on coumarin in cinnamon and other foods (updated September 27, 2012) German Federal Institute for Risk Assessment (BfR)Backs up: safety
  24. Alfalfa (Medicago sativa) Edible Wild FoodBacks up: safety
  25. European Union herbal monograph on Melilotus officinalis (L.) Lam., herba (EMA/HMPC/44166/2016, 2017) European Medicines Agency, Committee on Herbal Medicinal ProductsBacks up: safety
  26. Sweet Clover (yellow sweet clover, Melilotus officinalis) Foraging Texas (Mark Vorderbruggen)Backs up: safety, description
  27. Research-grade observations of white and yellow sweet clover (Melilotus albus, M. officinalis) within 25 km of DC, by month (fruiting) iNaturalistBacks up: season
  28. Research-grade observations of white and yellow sweet clover (Melilotus albus, M. officinalis) within 25 km of DC, by day (fruiting) iNaturalistBacks up: season
  29. Research-grade observations of white and yellow sweet clover (Melilotus albus, M. officinalis) within 25 km of DC, by day (flowering) iNaturalistBacks up: season
  30. Research-grade observations of white and yellow sweet clover (Melilotus albus, M. officinalis) within 25 km of DC, by day (all observations) iNaturalistBacks up: season
  31. Melilotus albus (White Melilot) Plants For A Future (PFAF) databaseBacks up: uses
  32. Sweet Clover (Melitotus: Condiment to Tea to Blood Thinner) Eat The Weeds (Green Deane)Backs up: uses, safety, habitat, description