Are Forget Me Nots Perennials? Which Parts of That Answer Are Fine

Woodland forget-me-not (Myosotis sylvatica) is a short-lived perennial that North Carolina State Extension also lists as an annual and a biennial: plants typically stand 6 to 12 inches tall, are hardy in USDA zones 3a through 8b, and bloom in April and May, with some later flowers in mid-summer. Water forget-me-not (Myosotis scorpioides) is a true herbaceous perennial in the same Extension profiles, typically about 10 inches tall (sometimes 18 inches), hardy in USDA zones 5a through 9b, and in bloom from mid-summer into early fall. They do not share a life cycle, a moisture spec, or the same legal status. Treating them as one device is the part of the common answer that is not fine.

I spend my working life matching a sensor point list to as-built drawings. A clean model that repeats a value is not proof the physical device is still the one on the drawing. A forget-me-not patch that comes back every spring has the same problem: the blue may return while the original crown does not.

Which forget-me-not is a true perennial, and which only looks like one?

The USDA PLANTS Database records both Myosotis sylvatica and Myosotis scorpioides with Duration: Perennial, and both as introduced in the lower 48 states. That federal duration field is a taxonomic category. It is not an acceptance test for a garden bed.

North Carolina State Extension is the as-built drawing I would sign against. For woodland forget-me-not it lists Life Cycle as Annual, Biennial, and Perennial on the same page. The plant is a short-lived perennial best grown as an annual, or as a biennial by sowing seed in mid-summer for bloom the following year. To grow it as an annual, start seed indoors about 8 to 10 weeks before the last spring frost. The stand then persists by freely, and sometimes aggressively, self-seeding.

University of Maine Cooperative Extension calls Myosotis sylvatica a winter-hardy biennial, often grown as an annual, that functions almost as a perennial because it is a prodigious self-sower. Successive generations are not the same plant.

Water forget-me-not is a different device. NC State lists its Life Cycle as Perennial only: a marginally aquatic herb that spreads by creeping rhizomes, will grow in up to 3 inches of standing water, and forms dense colonies. The Old Farmer’s Almanac calls M. scorpioides a true perennial and M. sylvatica the common biennial. Merging them under one common name is the override that makes the twin messy.

How do woodland and water forget-me-nots differ once you drop the common name?

The AI Overview on this query names both species. Shared packaging is more likely to send the wrong plant to a stream bank than the annual-versus-perennial label alone.

| Property | Woodland forget-me-not (Myosotis sylvatica) | Water forget-me-not (Myosotis scorpioides) | | --- | --- | --- | | Life cycle in the garden | Short-lived perennial; NC State also lists annual and biennial; self-sows | True herbaceous perennial; rhizomatous | | Mature height | NC State: 6 in to 1 ft | NC State: typically 10 in, sometimes 18 in; USDA PLANTS mature height 1.5 ft | | USDA garden zones | NC State: 3a-8b | NC State: 5a-9b | | Bloom window | NC State: April-May, plus sporadic mid-summer | NC State: mid-summer to early fall; USGS NAS identification: May-September | | Moisture | Moist, well-drained woodland soil; shallow standing water tolerated | Consistently moist to wet; up to 3 in of standing water | | How it spreads | Seed, sometimes aggressively; stem bases can root and make clonal offsets | Creeping rhizomes plus seed; USDA PLANTS: seed spread Rapid, vegetative spread Moderate | | Example legal status | Wisconsin NR 40 Restricted (effective May 1, 2015) | Prohibited in Connecticut, Massachusetts, and New Hampshire; Wisconsin NR 40 Restricted |

Alpine forget-me-not (Myosotis alpestris) sits off to the side. The Old Farmer’s Almanac calls it a short-lived dwarf perennial growing to 6 inches. I have not pulled a separate Extension spec sheet for it, so I will not assign it the woodland or water numbers.

NC State gives both species full sun (6 or more hours) or partial shade (2 to 6 hours). Woodland forget-me-not wants afternoon shade in hot summer climates. Water forget-me-not wants wet soil more than a particular hour-count of sun. If the tag says only “forget-me-not,” read the Latin name before the plant leaves the nursery.

Which published numbers belong on the tag, and which belong to a different instrument?

A commissioning package fails when two instruments report different values and nobody writes down which instrument was which. The figures below are real. They are not interchangeable.

Mature height for woodland forget-me-not is the cleanest reading. NC State’s Dimensions field is Height: 0 ft 6 in to 1 ft 0 in. Kitchen Garden Seeds’ sowing sheet for Myosotis sylvatica gives the same 6 to 12 inches.

Water forget-me-not height depends on which field you opened. NC State’s prose says typically 10 inches, sometimes 18 inches; its Dimensions field is 6 inches to 1 foot. USDA PLANTS lists Height, Mature (feet) as 1.5. USGS NAS identification describes an erect perennial 4 to 24 inches tall; the Size field on the same profile says 6 to 12 inches. The 10-inch typical height is the garden number. The USDA 1.5-foot figure and the USGS 24-inch ceiling are range limits.

Bloom season splits the same way. Woodland forget-me-not flowers, per NC State, in April and May, with some sporadic mid-summer bloom. Water forget-me-not flowers, per NC State, from mid-summer to early fall. USGS NAS identification says M. scorpioides blooms from May to September; the Great Lakes Ecology section extends that to May to October. USDA PLANTS uses the coarser category “Mid Spring.” Date a woodland display to April-May.

Hardiness is the zone map versus a survival temperature. NC State places woodland forget-me-not in USDA zones 3a through 8b and water forget-me-not in 5a through 9b. Swallowtail Garden Seeds says the water species is winter hardy to zone 3. USDA PLANTS lists Temperature, Minimum (°F) as -33 for M. scorpioides, which the USGS Great Lakes fact sheet attributes to USDA PLANTS (2013). Minus 33°F sits in USDA zone 3b. The zone 3 survival claim and the zone 5-9 garden-performance range can both be true: one is a kill temperature, the other is where Extension expects the plant to behave in a bed.

Germination temperature is a seed-sheet number, and the two species do not share one sheet. Kitchen Garden Seeds specifies 55°-65°F for Myosotis sylvatica, with germination in 14 to 21 days, seeds pressed onto the surface because light aids germination. Swallowtail specifies 65°F for water forget-me-not, with germination in 10 to 20 days, seed pressed in and not covered.

Seed-starting lead time is two clocks. For same-year bloom of woodland forget-me-not as an annual, NC State says start indoors about 8 to 10 weeks before the last spring frost. Kitchen Garden Seeds says start indoors 6 to 8 weeks before transplanting outside. Those clocks start at different events: last frost versus transplant day. For next year’s bloom, University of Maine Extension recommends sowing no later than mid-summer so seedlings establish before frost. I have not run a germination trial of my own.

Where is forget-me-not listed as invasive, and where can you still plant it?

“Forget-me-not invasive” is a legal question before it is a taste question. The answer is regional, and it is species-specific.

Wisconsin is the clearest dual listing. Chapter NR 40 (DNR file dated V.2026.04.09) places both Myosotis scorpioides (aquatic forget-me-not) and Myosotis sylvatica (woodland forget-me-not) in the Restricted category, effective May 1, 2015. Restricted plants may not be transported, transferred, or introduced without a permit; possession (other than fish or crayfish) is allowed. The DNR fact sheet states that aquatic forget-me-not can form large monocultures near streams and threaten intermediate spike-sedge (Eleocharis intermedia) and winged monkeyflower (Mimulus alatus).

Connecticut, Massachusetts, and New Hampshire prohibit the water species. Connecticut General Statutes §22a-381d, on or after October 1, 2005, bans import, sale, purchase, transplant, cultivation, and distribution of Myosotis scorpioides. The Massachusetts Prohibited Plant List names the same species. New Hampshire Env-Wq 1303.02 lists it (the rule text spells it “scorpiodies”) among prohibited exotic aquatic weeds under RSA 487:16-a. Go Botany marks it present, invasive, and prohibited in those three states.

Maine is a watch list, not a ban. The Maine Natural Areas Program Advisory List of Invasive Plants (2019) ranks water forget-me-not as 2-Very invasive in wetlands, status Widespread, and states the list is informational and non-regulatory.

Swallowtail Garden Seeds will not ship water forget-me-not seed to Connecticut, Massachusetts, or Wisconsin, yet the same catalog page says the plant “is not invasive.” I would not sign that sentence. USDA PLANTS records Rapid seed spread and Moderate vegetative spread. USGS NAS documents introduction to the Great Lakes Basin in 1886 and treats the species as widespread in all Great Lakes states. An AI Overview that repeats “does not spread aggressively” is quoting the catalog, not the agency files.

NC State says both species are listed as a noxious weed in one or more Midwestern states. Wisconsin is the Midwestern listing I verified on the current NR 40 plant list. I have not verified a separate Illinois or Indiana statute.

When should you plant forget-me-not seeds?

Match the clock to the life cycle you actually want. Woodland forget-me-not has two legitimate schedules. Water forget-me-not is a perennial with a different moisture spec and, in several states, a legal stop.

1. Read the Latin name on the packet. Myosotis sylvatica is the woodland biennial or short-lived perennial. Myosotis scorpioides is the water perennial. If the packet says only “forget-me-not,” do not sow it until the species is named.
2. Check your state's list for that species. Wisconsin restricts both. Connecticut, Massachusetts, and New Hampshire prohibit the water species. Maine’s advisory list is non-regulatory.
3. Pick the woodland clock if you are growing M. sylvatica where it is legal. For bloom this spring, NC State’s annual path is to start seed indoors about 8 to 10 weeks before the last spring frost, on the surface, at Kitchen Garden Seeds’ 55°-65°F range. For bloom next spring, Maine Extension wants seed in the ground by mid-summer.
4. Match moisture before you commit the water species. NC State plants M. scorpioides in consistently moist to wet soil, including up to 3 inches of water over the crown in a container. USGS NAS notes that it may form rafts in slow-moving streams.

Kitchen Garden Seeds also allows direct-sowing woodland seed as soon as the ground can be worked. Thin to 10 to 12 inches. I prefer the mid-summer biennial sowing for a spring carpet under bulbs. The 8-to-10-week indoor start is the override for seed bought in March.

What should you do with forget-me-nots after they flower?

After woodland forget-me-not flowers, the decision is whether you want the next generation. NC State says you can deadhead immediately to encourage flowers and to prevent excessively seeding. If the patch is already larger than the bed, pull plants as the blue fades, before the nutlets drop.

Water forget-me-not also walks on rhizomes. NC State’s control move in a water garden is a 1-gallon container with up to 3 inches of water over the crown. On a muddy bank, that containment is gone. Do not compost live rhizomes into a pile that drains toward a creek. Powdery mildew and rust are the disease notes on both NC State pages.

A repeating blue haze is a simulation match. It is not a signed-off perennial crown. If the species on the tag was wrong, identify the actual device, check the rule sheet, and remove what does not belong on that loop.

FAQ

Do forget-me-nots come back every year?

Woodland forget-me-not often returns as new seedlings after the original crown is gone. North Carolina State Extension calls Myosotis sylvatica a short-lived perennial best grown as an annual, and University of Maine Extension says it functions almost as a perennial because it self-sows. Water forget-me-not (Myosotis scorpioides) is a true perennial that also spreads by rhizomes.

Do forget-me-nots like sun or shade?

North Carolina State Extension lists both woodland and water forget-me-not for full sun (6 or more hours) or partial shade (2 to 6 hours). Woodland plants want afternoon shade in hot summer climates and moist, well-drained soil. Water forget-me-not wants consistently wet ground or up to 3 inches of standing water more than it wants a particular light reading.

How invasive are forget-me-nots?

It depends on the species and the state. Wisconsin NR 40 lists both Myosotis sylvatica and Myosotis scorpioides as Restricted as of May 1, 2015. Connecticut, Massachusetts, and New Hampshire prohibit the water species. Maine’s 2019 advisory list ranks water forget-me-not as very invasive but non-regulatory. Elsewhere they can still self-sow or form rhizome mats.

What do you do with forget-me-nots after flowering?

Deadhead woodland forget-me-not if you do not want volunteers; North Carolina State Extension says immediate deadheading limits excessive seeding. Leave some seed heads only if you want next year’s carpet. Water forget-me-not also spreads by rhizomes, so keep crowns in a container near open water.

Are woodland forget-me-nots perennials?

North Carolina State Extension lists Myosotis sylvatica as annual, biennial, and perennial, and calls it a short-lived perennial best grown as an annual or sown in mid-summer as a biennial. The USDA PLANTS Database duration field says Perennial. In a garden, the stand usually persists by self-seeding after the original plant is gone.

When should I plant forget-me-not seeds?

For woodland forget-me-not bloom this year, North Carolina State Extension says start seed indoors 8 to 10 weeks before the last spring frost, at Kitchen Garden Seeds’ 55°-65°F germination range. For bloom next spring, University of Maine Extension wants seed in by mid-summer. Confirm the Latin name first, and skip water forget-me-not where it is prohibited.