Moon-phase planting is a real tradition documented across centuries of almanacs, but it is not an input in the soil-temperature and frost-date guidance land-grant extension services publish today. This page tracks the moon’s four primary phases across their roughly 29.5-day cycle (US Naval Observatory), sets two region-specific folk signs from old almanacs beside sourced measurable cues, and compares both against NOAA’s 1991-2020 frost-date normals through the planting calendar hub’s own data.
A note on how this page works. Everything below reports what a tradition holds, not a claim that it works. Where this page sets a folk sign beside NOAA’s frost-date normals, that is a comparison of two different kinds of record, a long-held observational tradition and a modern climate-station average, not a test of either one.
If You Are New to Almanac Timing, Start With These Four Phases
Four primary phases anchor every lunar calendar: New Moon, First Quarter, Full Moon and Last Quarter. The US Naval Observatory’s Astronomical Applications Department, which publishes the Dates of Primary Phases of the Moon service, uses this exact four-phase framing, and the cycle from one New Moon to the next runs an average of 29.5 days.
That single number, 29.5 days, is the thread running through the rest of this page. It sets how far apart the four primary phases fall (covered below), how long the informal week-long “moon phase” people picture actually spans, and how a countdown from New Moon to Full Moon works. For a day-by-day breakdown of which specific calendar dates suit which garden task under this tradition, see the best planting days by moon phase. Everything else on this page either explains the mechanics behind that four-phase system or sets a regional folklore sign beside a sourced, measurable comparison.
Almanac Signs by Region: What Growers in Different States Watched For
Old almanacs and regional planting lore carried signs that growers in a given area historically watched for, tied to a local plant or event rather than a fixed calendar date. Two of those regional folk planting signs have a live-confirmed source on both the folklore side and the measurable side, and this table ships only those two. Other regional signs exist in print but could not be closed against a working source during this page’s research, so they are left out rather than guessed at.
Regional Almanac Signs and Their Measurable Counterparts
| Region | Traditional sign | Typical timing | Related measurable variable |
|---|---|---|---|
| Great Lakes / Upper Midwest | Forsythia shrubs reaching full bloom, used today as a phenological indicator alongside growing-degree-day tracking (Michigan State University Extension) | March into April | Crabgrass begins germinating once soil hits 57-64°F at a one-inch depth, or roughly 200 accumulated growing degree days at a 50°F base (Purdue Turfgrass Science) |
| Pennsylvania / Mid-Atlantic | Groundhog Day: tradition holds that if the groundhog sees its shadow on February 2, winter continues six more weeks (The Old Farmer’s Almanac) | February 2, fixed date | Philadelphia’s NOAA/NCEI 1991-2020 last spring frost normal falls on April 2 |
The two rows are not documented the same way, and the difference matters. Groundhog Day is recorded as a tradition. Forsythia bloom is documented by Michigan State University Extension as a phenological indicator in present-day use, not as folklore. Neither row is a claim about what growers in either region report or believe today; no source behind this page surveys them. The forsythia row and the Groundhog Day row are picked up again later on this page, once against a documented caveat from the source itself and once against a computed comparison to frost-date timing.
Other regional planting signs are in wide circulation, including sayings tied to oak-leaf size in the Corn Belt and lilac bloom in the Northeast, but neither could be traced to a currently reachable extension or almanac page during this page’s research. Naming the sign without a working citation would turn a documented tradition into an invented one, so those rows stay out of the table rather than shipping unsourced. A two-row table built entirely from confirmed sources is worth more to a reader than a longer table with rows that cannot be checked.
Plant, Sow, or Set: How Old Almanacs Phrased Their Advice
Almanac-style planting guidance, old and current, does not use “plant,” “sow” and “set” as interchangeable words. “Sow” is reserved for seed going directly into soil or a tray, as in Clemson HGIC’s tomato guidance to “sow seed indoors six to eight weeks before the last frost date.” “Set” or “set out” describes moving an already-started seedling, bulb or clove into its growing spot, the step Clemson HGIC’s tomato page calls hardening off before transplanting. “Plant” functions as the umbrella term covering both, which is why bulb guidance such as Clemson HGIC’s instruction to “plant daffodils in October or November” reads correctly whether the reader is setting a bulb or direct-seeding.
This three-way split matters for a reader trying to follow old almanac wording literally: a line that says to sow a crop is describing a seed going into soil now, while a line that says to set a crop is describing a transplant step that happened weeks earlier, indoors. Old almanac wording is not more precise than modern extension wording on this point; both traditions use the same three verbs for the same three actions.
When Do the Four Lunar Phases Fall This Month
This page does not print a calendar date for the current month’s phases, because a printed date goes stale the moment the calendar turns. The pattern behind the question is fixed and does not go stale: the moon moves through its four primary phases, New Moon, First Quarter, Full Moon and Last Quarter, once every 29.5 days on average (US Naval Observatory), and that cycle repeats continuously.
To find this month’s actual dates, the US Naval Observatory’s Astronomical Applications Department publishes a Dates of Primary Phases of the Moon data service (aa.usno.navy.mil/data/MoonPhases) that returns exact dates and times for any year between 1700 and 2100, in Universal Time. NASA Science’s Moon Phases page (science.nasa.gov/moon/moon-phases) covers the same eight-phase cycle in plainer, descriptive language and is a reasonable second stop. Reading the current month’s dates from either source, rather than from a printed table that will not update, is the only way to get an accurate answer to this question.
Why Some Growers Stopped Following Moon-Phase Planting
The documented, sourced reason moon-phase timing receded from official planting guidance is institutional, not a rejection of the tradition itself. The Smith-Lever Act of 1914 formalized the Cooperative Extension Service, expanding USDA’s partnership with land-grant universities to apply agricultural research and deliver it through county-level extension offices (USDA National Institute of Food and Agriculture). Over the century since, extension programs standardized their planting recommendations around soil temperature, frost-date normals and growing degree days, the same measurable inputs behind every crop table on this site, rather than lunar phase.
That is a description of what extension guidance adopted, not a claim about what any individual grower privately believes or has stopped believing. No source behind this page surveys growers on the question, and this page does not invent one. What can be said, sourced, is narrower and more useful: the recommendation system that farmers, home gardeners and county extension agents are pointed toward today runs on soil temperature and frost timing, and lunar phase is not part of that system.
Almanac Wisdom Month by Month, January Through December
This calendar indexes eight of the twelve months, the ones where this site has folklore content grounded well enough to point a reader toward. The other four months are left blank on purpose rather than filled with a folklore claim invented to complete the row.
Almanac Wisdom Calendar, Month by Month
| Month | Folklore focus | Explored in depth |
|---|---|---|
| January | Winter night-sky markers and the tail end of the outdoor harvest window | winter harvest window timing |
| February | Imbolc, the seasonal midpoint tradition tied to the same date as the Groundhog Day sign above | Imbolc traditions |
| March | March wind folklore around the spring equinox | March wind folklore |
| April | Earliest spring blooms, including the forsythia cue covered in the table above | first flowers of spring |
| June | June bugs as a recurring early-summer seasonal marker | June bug seasonal timing |
| September | The fall equinox and its seasonal folklore | fall equinox traditions |
| October | Woolly worm banding, read in tradition as a sign of the coming winter’s severity | woolly worm folklore |
| December | The yule log tradition tied to the winter solstice | yule log and winter solstice |
May, July, August and November do not appear in this table. Each of this pillar’s individual month or holiday articles carries its own sourcing; this table exists to point a reader toward the right one, not to re-source every month’s folklore here. A calendar that filled in every month regardless of whether a sourced entry existed would look more complete at a glance, but it would be complete in appearance only, which is the opposite of what this page is trying to do.
Count Days From New Moon to Full Moon to Find Your Window
New Moon and Full Moon sit on opposite sides of the roughly 29.5-day cycle (US Naval Observatory), so counting from one to the other lands at about half that figure, roughly 14 to 15 days. That halving is this page’s own arithmetic applied to USNO’s published cycle length, not a separately stated duration from the source itself.
Because 29.5 does not split evenly, the real gap between a given New Moon and the Full Moon that follows it varies by roughly a day depending on where in the cycle it falls, which is exactly why a reader should read the actual dates off the US Naval Observatory’s Dates of Primary Phases service for their own month rather than assume every New Moon to Full Moon window is identical. The same 14-to-15-day span, run in reverse, describes the gap from Full Moon back to the New Moon before it.
How Many Days Does Each Moon Phase Actually Last
This is a precision question, and the honest answer depends on which of two things “moon phase” means. The US Naval Observatory’s four primary phases, New Moon, First Quarter, Full Moon and Last Quarter, are instants, single moments in time, not spans of days. What most people picture when they say a phase “lasts” about a week is a different, informal idea: the interval between one primary phase and the next.
That interval is this page’s own arithmetic, not a duration USNO or NASA states directly: 29.5 days divided by the four primary phases works out to roughly 7.4 days between one primary phase and the next. So “the moon is in its waxing gibbous phase” describes the several days between First Quarter and Full Moon, not a single fixed-length stage with a published start and end time. The instant is sourced; the week-long framing is a useful approximation this page built from that instant, and should be read as such.
What Happens If You Ignore Moon Phase Timing Entirely
Nothing changes in the measurable framework this site’s other planting-calendar content runs on. Land-grant extension planting guidance, the source behind this site’s soil-temperature and frost-date tables, does not list lunar phase as an input at all, so skipping it does not remove a step from that guidance. A gardener following a soil-temperature threshold or a frost-date window, the two measurable cues extension programs actually publish, is already following a planting method that never asked for a moon phase in the first place.
That is a statement about what the sourced guidance includes and excludes, not a claim that following or ignoring lunar timing changes anything about a garden’s outcome. No source behind this page tracks that comparison, and this page does not invent a result for it. What is documented is narrower: the measurable planting system this site’s other clusters draw from runs entirely on soil temperature, frost-date normals and growing degree days, with no lunar-phase step to skip.
A reader is not actually choosing between two competing planting systems here. Soil temperature and frost-date timing answer when a crop is ready to go in the ground in a specific location; the lunar calendar answers an older question about which day within an already-suitable window a tradition favors. The two are not mutually exclusive, and this page does not ask a reader to pick one over the other.
Traditional Folklore vs Measurable Signs: Soil Temperature Side by Side
Setting the two rows from the regional-signs table beside their measurable counterparts surfaces a caveat the source itself states. Michigan State University Extension’s crabgrass-timing coverage frames the forsythia-bloom sign as one of several tools growers use alongside growing-degree-day tracking, and states directly that “the GDD models are meant to serve as guides, not absolutes.” MSU’s broader crabgrass-timing coverage also notes that a shift toward cooler temperatures shifts that window rather than fixing it to one date. A folk sign built around a single visual cue carries that same built-in uncertainty: a warm or cool spring shifts forsythia bloom the same way it shifts the GDD model itself.
The measurable side of both rows, by contrast, is anchored to a stated threshold or a stated station normal: crabgrass germination at 57-64°F soil measured specifically at a one-inch depth (Purdue Turfgrass Science), and Philadelphia’s April 2 last-frost normal from NOAA/NCEI’s 1991-2020 climate normals. For a reader who wants the same kind of station-anchored figure for a specific US crop and region rather than a regional folk sign, this site’s planting calendar hub builds that comparison directly from NOAA and USDA data.
What ‘Waxing’ and ‘Waning’ Actually Mean on a Moon Calendar
NASA Science’s Moon Phases page and the US Naval Observatory’s own phase explanation both describe the same eight-phase cycle: New Moon, Waxing Crescent, First Quarter, Waxing Gibbous, Full Moon, Waning Gibbous, Last Quarter (NASA’s page uses “Third Quarter” for the same point) and Waning Crescent. “Waxing” describes the stretch where the illuminated fraction of the Moon’s disk is increasing, running from New Moon through Full Moon. “Waning” describes the opposite stretch, where the illuminated fraction is decreasing, running from Full Moon back to New Moon.
“Crescent” and “gibbous” describe shape rather than direction: crescent means less than half the visible disk is lit, gibbous means more than half but not fully lit. Put together, “waxing gibbous” names a specific several-day stretch, more than half lit and still brightening, between First Quarter and Full Moon, while “waning crescent” names the mirror stretch, less than half lit and still dimming, in the days right before the next New Moon.
How Many Almanac Traditions Overlap With Frost Date Timing
This page sources only two regional folk signs against frost-date timing, and two cases are too few to state as a rate or a ratio; doing so would be false precision this page will not manufacture. What can be reported honestly is each sign’s timing set beside its region’s NOAA-normal last spring frost date, as two individual comparisons, not scored against any inside-or-outside tolerance band.
Wisconsin Horticulture states that forsythia in the upper Midwest “typically bloom starting in late March to mid-April for one to two weeks.” Michigan State University Extension’s own page notes forsythia blooming on its campus on March 15, 2024, but that same page calls the spring in question unusually early, citing 297 accumulated growing degree days by that date against 78 GDD on the same date the year before, so that single campus date is not used here as a typical bloom time. Michigan’s NOAA/NCEI last spring frost normal, at the Detroit Metro Ap station, falls on April 20, after the entire forsythia bloom range stated above.
The Groundhog Day sign falls on a fixed February 2 date. Pennsylvania’s NOAA/NCEI last spring frost normal, at the Philadelphia Intl Ap station, falls on April 2, roughly eight and a half weeks later. Even the tradition’s own claimed shift, six more weeks of winter counted forward from February 2, lands near March 16, still about two and a half weeks ahead of Philadelphia’s actual station-normal last frost.
Both comparisons are reported here as what they are, a regional seasonal marker set beside a station-specific climate average, not as evidence that either tradition is wrong for what it is: a regional, seasonal marker rather than a station-precise instrument.
Old Almanac Sayings vs Modern Frost-Date Tables: What Changed
The core change between an old almanac saying and a modern NOAA/NCEI frost table is precision, not accuracy in some absolute sense. A folk sign like forsythia bloom or Groundhog Day names a region and a rough seasonal window, sourced to observation repeated across many years in one place. A NOAA/NCEI 1991-2020 climate normal names one specific weather station and reports a median calendar date built from thirty years of that station’s own recorded data, the same kind of figure behind every state row in this site’s frost-date table.
Both record types are doing something real, just at different resolutions. The regional sign compresses decades of scattered local observation into one memorable rule of thumb, while the station normal compresses thirty years of one station’s daily readings into a single date. Michigan State University Extension’s own caveat, that its degree-day model is a guide rather than an absolute, applies in spirit to the frost-date normal too: a “normal” is a median across thirty years, not a guarantee for any single year, which is exactly why every article on this site that uses one also points readers back to their own local NOAA station.
What changed is not that one record type replaced the other in accuracy. What changed is the tool available to build the record. A regional folk sign was, for most of the history covered by an almanac like the one traced above, the only widely shared timing tool a household had. A station-specific climate normal is a twentieth and twenty-first century product of continuous instrument records and standardized thirty-year averaging, a resolution no observational tradition could reach on its own. Reading them as competing claims about the same thing misses that they were built to answer different questions with the tools available at the time.
Frequently Asked Questions
Do land-grant extension services include moon phase in their planting guidance? No. The Cooperative Extension System, formalized by the Smith-Lever Act of 1914 (USDA National Institute of Food and Agriculture), builds its planting recommendations around soil temperature, frost-date normals and growing degree days. None of the extension pages this site draws timing figures from name lunar phase as an input.
What is the difference between an almanac and a planting calendar? An almanac, in the tradition of publications like The Old Farmer’s Almanac, bundles astronomical data, weather outlooks and folklore signs into one annual reference. A planting calendar, as this site and land-grant extension programs build them, is narrower by design: it converts a single measurable input, usually a frost-date normal or a soil-temperature threshold, into a sowing or transplanting window for one crop.
Do all regions in the US follow the same almanac traditions? No. The two regional signs sourced for this page, a forsythia-bloom cue in the Great Lakes and Upper Midwest and the Groundhog Day tradition centered on Pennsylvania, are tied to different plants, animals and calendar dates. A folk sign built around a species or an event native to one region does not transfer cleanly to a region where that species or event does not occur.
How far back are lunar planting traditions recorded? The most concretely documented lineage on this page is The Old Farmer’s Almanac itself, first published in 1792 and continuously published since (almanac.com). Lunar-linked planting folklore is generally understood to predate that publication by a considerable margin, but this page anchors its date claim only to what is directly sourced, the Almanac’s own 1792 founding, rather than an undocumented earlier estimate.
Can folklore signs and frost-date data both be tracked in the same journal? There is no technical reason they could not be. A reader could log a regional folk sign, such as a forsythia bloom date, alongside their own local NOAA station’s frost-date normal and soil-temperature readings, and compare the two over several seasons. This page does not claim any reader already does this; it is offered here as one way the two record types in this article could be used side by side.
Sources
- US Naval Observatory Astronomical Applications Department, Dates of Primary Phases of the Moon: https://aa.usno.navy.mil/data/MoonPhases
- US Naval Observatory Astronomical Applications Department, Moon Phases FAQ: https://aa.usno.navy.mil/faq/moon_phases
- NASA Science, Moon Phases: https://science.nasa.gov/moon/moon-phases/
- NOAA/NCEI 1991-2020 Climate Normals, via this site’s frost-date-by-state data asset
- Michigan State University Extension, Timing Crabgrass Preemergence Applications in Spring: https://www.canr.msu.edu/news/timing_crabgrass_pre_emergence_applications
- Purdue Turfgrass Science, When Will Crabgrass Germinate: https://turf.purdue.edu/when-will-crabgrass-germinate/
- Wisconsin Horticulture, Forsythia, Forsythia spp.: https://hort.extension.wisc.edu/articles/forsythia-forsythia-spp/
- The Old Farmer’s Almanac, Groundhog Day: https://www.almanac.com/groundhog-day
- The Old Farmer’s Almanac, History of The Old Farmer’s Almanac: https://www.almanac.com/history-old-farmers-almanac
- USDA National Institute of Food and Agriculture, Extension: https://www.nifa.usda.gov/about-nifa/how-we-work/extension
Last verified: 2026-08-15, against the US Naval Observatory, NASA Science, Michigan State University Extension, Purdue Turfgrass Science, The Old Farmer’s Almanac and USDA National Institute of Food and Agriculture pages cited above, plus this site’s own NOAA/NCEI-sourced frost-date data asset.